Staff

Abstract:
Vacancy engineering offers an attractive approach to improving the surface properties and electronic
structure of transition metal nanomaterials. However, simple and cost-effective methods for introducing
defects into nanomaterials still face great challenges. Herein, we propose a facile room temperature
two-step technique that utilizes Fe as the dopant to enhance S vacancies in cobalt-based metal–organic
frameworks (MOFs). The Fe–Co-MOF was converted into a hollow Fe–Co3S4 confined in CoMo2S4 to
form Fe–Co3S4@CoMo2S4 nanosheets. The as-prepared material showed enhanced charge storage
kinetics and excellent properties as an electrode material for supercapacitors. The obtained
nanostructure displayed a high specific capacitance (980.3 F g−1 at 1 A g−1) and excellent cycling stability
(capacity retention of 96.5% after 6000 cycles at 10 A g−1). Density functional theory (DFT) calculations
show that introducing defects into the nanostructures leads to more electrons appearing near the Fermi
level, which is beneficial for electron transfer during electrochemical processes. Thus, this work provides
a rational cost-effective strategy for introducing defects into transition metal sulfides and may serve as
a potential means to prepare electrode materials for energy storage.

Abstract:
The rational synthesis and tailoring of metal-organic frameworks (MOFs) with multifunctional micro/nanoarchitectures have emerged as a subject of significant academic interest owing to their promising potential for utilization in advanced energy storage devices. Herein, we explored a category of three-dimensional (3D) NiCo2S4 nanospikes that have been integrated into a 1D Fe3C microarchitecture using a chemical surface transformation process. The resulting electrode materials, i.e., Fe3C@NiCo2S4 nanospikes, exhibit immense potential for utilization in high-performance hybrid supercapacitors. The nanospikes exhibit an elevated specific capacity (1894.2 F g-1 at 1 A g-1), enhanced rate capability (59%), and exceptional cycling stability (92.5% with 98.7% Coulombic efficiency) via a charge storage mechanism reminiscent of a battery. The augmented charge storage characteristics are attributed to the collaborative features of the active constituents, amplified availability of active sites inherent in the nanospikes, and the proficient redox chemical reactions of multi-metallic guest species. When using nitrogen-doped carbon nanofibers as the anode to fabricate hybrid supercapacitors, the device exhibits high energy and power densities of 62.98 Wh kg-1 and 6834 W kg-1, respectively, and shows excellent long-term cycling stability (95.4% after 5000 cycles), which affirms the significant potential of the proposed design for applications in hybrid supercapacitors. The DFT study showed the strong coupling of the oxygen from the electrolyte OH- with the metal atom of the nanostructures, resulting in high adsorption properties that facilitate the redox reaction kinetics.

Keywords:
defect engineering, Nanospike, advanced electrode, hybrid, MOF, Supercapacitor

Abstract:
Fe-based nanostructures have possessed promising properties that make it suitable for chiral sensing and imaging applications owing to their ultra-small size, non-toxicity, biocompatibility, excellent photostability, tunable fluorescence, and water solubility. This review summarizes the recent research progress in the field of Fe-based nanostructures and places special emphases on their applications in chiral sensing and imaging. The synthetic strategies to prepare the targeted Fe-based structures were also introduced. The chiral sensing and imaging applications of the nanostructures are discussed in details.

Abstract:
Tuning the electronic structure of single-atom catalysts through dimeric single-atom formation could be an innovative approach to increasing their energy storage activity, but the process of achieving this is challenging. In this study, we designed a simple technique to obtain Nisingle bondCo single atom dimers (SADs) anchored on N-doped molybdenum carbide (N-Mo2C) through in-situ encapsulation of Nisingle bondCo into molybdenum polydopamine, followed by annealing with optimal tuning of nitrogen dopant. The Nisingle bondCo atomic level coordination was confirmed with X-ray absorption spectroscopy. When used as energy storage supercapacitor, The NiCo-SADs showed enhanced specific capacity (1004.8 F g−1 at 1 A g−1), enhanced rate capability (75 %), and exceptional cycling stability (93.6 % with 98.5 % coulombic efficiency) via a dominant capacitive charge storage. The augmented charge storage characteristics are attributed to the collaborative features of the active Nisingle bondCo constituents acting as electron reservoir for effective adsorption of HO− ion during the electrochemical process. The DFT study showed thermodynamically favorable OH− adsorption between the three metal bridges that promoted redox reaction kinetics and enhanced conductivity for the NiCo-SADs. When using N-Mo2C as the anode to fabricate hybrid supercapacitors, the device exhibits high energy density of 69.69 Wh kg−1 at power density of 8200 W kg−1, respectively and shows excellent long-term cycling stability (93.42 % after 3000 cycles), which affirms the potential of the assembled device for applications in solid state supercapacitors.

Abstract:
Photocatalytic CO2 reduction has emerged as a promising strategy for converting solar energy into valuable chemicals, capturing the attention of scientists across various disciplines. Organic and inorganic perovskites, particularly methylammonium lead bromide (MAPbBr3), have demonstrated potential in this field due to their remarkable visible-light response and carrier transport properties. However, the catalytic performance of pristine MAPbBr3 has been limited by severe charge recombination, hindering its applicability in photocatalytic systems. Here, we show that a MAPbBr3/Bi2WO6 (MA/BWO) heterojunction significantly enhances photocatalytic CO2 reduction performance compared to individual pristine MA or BWO. This enhancement is evidenced by the superior performance of the 25% MA/BWO composite, which exhibits CO and CH4 release rates of 1.82 μmol/g/h and 0.08 μmol/g/h, respectively. This improvement is attributed to the direct Z-scheme heterojunction formed between MAPbBr3 and Bi2WO6, which facilitates efficient charge separation and suppresses charge recombination. The results challenge the previous understanding of MAPbBr3-based photocatalysts and demonstrate a novel approach for developing highly active organic and inorganic perovskite photocatalysts. The successful application of the MA/BWO heterojunction in photocatalytic CO2 reduction expands the scope of organic and inorganic perovskites in the field of renewable energy conversion. By providing a broader perspective, our findings contribute to the ongoing efforts towards sustainable energy solutions, appealing

Abstract:
he synthesis, photophysicochemical and photodynamic therapy (PDT) activities of benzothiazole substituted zinc phthalocyanine (Pc): 1 (asymmetrically substituted and composed of no charges), 2 (asymmetrically substituted and composed of three positive charges), and 3 (symmetrically substituted and composed of four positive charges), are presented. The triplet and singlet oxygen quantum yields were highest for complex 2 showing the importance of asymmetry and charge. The complexes are covalently and non-covalently linked to B doped detonation nanodiamonds (B@DNDs) to yield nanohybrids (B@DNDs-1, B@DNDs-2, B@DNDs-3). The presence of B@DNDs, asymmetry and positive charge resulted in improved PDT with the lowest cell viability being observed for B@DNDs-2 at 5%. The cell viability ranged from 5% to 7% for the nanohybrids compared to 19–26% for Pcs alone.

Abstract:
We report on biosynthesis of silver nanoparticles using aqueous leaf extract of Euphorbia sanguinea and its photocatalytic degradation of Congo red dye and melanogenesis inhibition activity of mushroom tyrosine enzyme. Surface Plasmon resonance bands obtained from UV-Vis spectra were within the range 430–436 nm. FT-IR studies reveal the presence of functional groups of the plant metabolites used as stabilizing agents of nanoparticles. The shape of silver nanoparticles is spherical with size ranges about 20–28.8 nm as confirmed by SEM. XRD patterns displayed well-defined crystalline peaks corresponding to the face-centred cubic structures of metallic silver nanoparticles. The results of photocatalysis showed high photocatalytic efficiency of 86% and 90% within 5 min and 60 min, respectively at a rate of solar radiation of in the degradation of Congo red dye. The AgNPs gave dose dependent melanogenesis inhibition activity with IC50 of 71.96 µg/ml, showing non competitive mode of inhibition

Abstract:
A feasible nanoscale framework of heterogeneous plasmonic materials and
proper surface engineering can enhance photoelectrochemical (PEC)
water-splitting performance owing to increased light absorbance, efficient
bulk carrier transport, and interfacial charge transfer. This article introduces a
new magnetoplasmonic (MagPlas) Ni-doped Au@FexOy nanorods (NRs)
based material as a novel photoanode for PEC water-splitting. A two stage
procedure produces core–shell Ni/Au@FexOy MagPlas NRs. The first-step is
a one-pot solvothermal synthesis of Au@FexOy. The hollow FexOy nanotubes
(NTs) are a hybrid of Fe2O3 and Fe3O4, and the second-step is a sequential
hydrothermal treatment for Ni doping. Then, a transverse magnetic
field-induced assembly is adopted to decorate Ni/Au@FexOy on FTO glass to
be an artificially roughened morphologic surface called a rugged forest,
allowing more light absorption and active electrochemical sites. Then, to
characterize its optical and surface properties, COMSOL Multiphysics
simulations are carried out. The core–shell Ni/Au@FexOy MagPlas NRs
increase photoanode interface charge transfer to 2.73 mAcm−2 at 1.23 V RHE.
This improvement is made possible by the rugged morphology of the NRs,
which provide more active sites and oxygen vacancies as the hole transfer
medium. The recent finding may provide light on plasmonic photocatalytic
hybrids and surface morphology for effective PEC photoanodes.

Abstract:
The integration of different precursor components to form single nanostructures via one-step synthesis process is mostly restricted by the compatibility and complexity of components. Herein, a highly uniform, spherical, hollowed, and hierarchical iron oxide-wrapped Mo–polydopamine is synthesized using a one-pot liquid-phase reaction at room temperature. Mo2C is doped with Fe3O4 to harness the rich electrons in Fe dopants for effective lowering of the unoccupied d-orbitals in Mo. The surface conductivity of the as-prepared nanostructures is enhanced by decorating them with gold nanoparticles utilizing strong interaction of Au and amine. The nanocomposites are converted into carbidic hollowed structures via an annealing process without any distortion in morphology. The well-organized structure and nanosize of the particles provide efficient catalytic performance for hydrogen evolution reaction in acidic media. MoFe–C@Au exhibits a very positive onset potential of 2 mV, low Tafel slope of 50.1 mV dec^-1, and remarkable long- term stability.

Keywords:
electrocatalysts,hierarchical syntheses,hydrogen evolution,molybdenum,polydopamine

Abstract:
Hydrogen produced by electrochemical water splitting is considered to be a sustainable fuel source, an
ideal way to solve the energy problem and its environmental challenges. However, industrial production
of hydrogen from water splitting is mainly hindered by sluggish kinetics of the oxygen evolution reaction
(OER) at the anode and the hydrogen evolution reaction (HER) at the cathode in an alkaline solution due
to the difficulty in forming binding protons. Thus, the construction of a highly active and cost-effective
catalyst with abundant oxygen vacancies is critical for enhancing the reaction efficiency and decreasing
the required overpotential. Due to earth-abundance and electrocatalytic activities, Ni-based ultrathin
nanostructures (Ni-utNSs) have attracted immense attention for overall water splitting. Herein, we have
presented a complete summary of recent advancements in Ni-utNSs for overall electrochemical water
splitting. After discussing unique advances in Ni-utNSs, we discussed their properties and crystal
structures. The HER, OER, and oxygen reduction reaction (ORR) mechanisms were briefly discussed. We
also discussed several Ni-utNS manufacturing techniques, as well as in situ and ex situ characterization
and computer modeling. Furthermore, the electrochemical water splitting of Ni-utNSs is addressed. This
review can help readers understand the recent progress of Ni-utNS catalysts and gain insight into the
rational design of Ni-utNS catalysts with high electrocatalytic activity.

Abstract:
The global pandemic of COVID-19 is an example of how quickly a disease-causing virus can take root and threaten our civilization. Nowadays, ultrasensitive and rapid detection of contagious pathogens is in high demand. Here, we present a novel hierarchically porous 3-dimensional magnetic molybdenum trioxide–polydopamine-gold functionalized nanosphere (3D mag-MoO3–PDA@Au NS) composed of plasmonic, semiconductor, and magnetic nanoparticles as a multifunctional nanosculptured hybrid. Based on the synthesized 3D mag-MoO3–PDA@Au NS, a universal “plug and play” biosensor for pathogens is proposed. Specifically, a magnetically-induced nanogap-enhanced Raman scattering (MINERS) detection platform was developed using the 3D nanostructure. Through a magnetic actuation process, the MINERS system overcomes Raman signal stability and reproducibility challenges for the ultrasensitive detection of SARS-CoV-2 spike protein over a wide dynamic range up to a detection limit of 10−15 g mL−1. The proposed MINERS platform will facilitate the broader use of Raman spectroscopy as a powerful analytical detection tool in diverse fields.

Abstract:
Chains of alternating semiconductor nanocrystals are complex nanostructures that can offer control over photogenerated charge carriers dynamics and quantized electronic states. We develop a simple one-pot colloidal synthesis of complex Cu1.94S-CdS and Cu1.94S-ZnS nanochains exploiting an equilibrium driving ion exchange mechanism. The chain length of the heterostructures can be tuned using a concentration dependent cation exchange mechanism controlled by the precursor concentrations, which enables the synthesis of monodisperse and uniform Cu1.94S-CdS-Cu1.94S nanochains featuring three epitaxial junctions. These seamless junctions enable efficient separation of photogenerated charge carriers, which can be harvested for photocatalytic applications. We demonstrate the superior photocatalytic activity of these noble metal free materials through solar hydrogen generation at a hydrogen evolution rate of 22.01 mmol g–1 h–1, which is 1.5-fold that of Pt/CdS heterostructure photocatalyst particles.

Abstract:
Melanin nanoparticles are known to be biologically benign to human cells for a wide range of concentrations in a high glucose culture nutrition. Here, we show cytotoxic behavior at high nanoparticle and low glucose concentrations, as well as at low nanoparticle concentration under exposure to (nonionizing) visible radiation. To study these effects in detail, we developed highly monodispersed melanin nanoparticles (both uncoated and glucose-coated). In order to study the effect of significant cellular uptake of these nanoparticles, we employed three cancer cell lines: VM-M3, A375 (derived from melanoma), and HeLa, all known to exhibit strong macrophagic character, i.e., strong nanoparticle uptake through phagocytic ingestion. Our main observations are: (i) metastatic VM-M3 cancer cells massively ingest melanin nanoparticles (mNPs); (ii) the observed ingestion is enhanced by coating mNPs with glucose; (iii) after a certain level of mNP ingestion, the metastatic cancer cells studied here are observed to die—glucose coating appears to slow that process; (iv) cells that accumulate mNPs are much more susceptible to killing by laser illumination than cells that do not accumulate mNPs; and (v) non-metastatic VM-NM1 cancer cells also studied in this work do not ingest the mNPs, and remain unaffected after receiving identical optical energy levels and doses. Results of this study could lead to the development of a therapy for control of metastatic stages of cancer.

Keywords:
melanoma, melanin nanoparticles, cytotoxicity, laser medical applications, hyperthermia

Abstract:
Colloidal synthesis of photocatalysts with potential to overcome the drawback of low photocatalytic efficiency brought by charge recombination and narrow photo-response has been a challenge. Herein, a general and facile colloidal approach to synthesize orthorhombic phase Bi2S3 particles with rod and flower-like morphology is reported. We elucidate the formation and growth process mechanisms of these synthesized nanocrystals in detail and cooperate these Bi2S3 particles with metallic gold nanoparticles (AuNPs) to construct heterostructured photocatalysts. The unique properties of AuNPs featuring tunable surface plasmon resonance and large field enhancement are used to sensitize the photocatalytic activity of the Bi2S3 semiconductor particles. The morphology, structure, elemental composition, and light absorption ability of the prepared catalysts are characterized by (high-resolution) transmission electron microscopy, scanning electron microscopy, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, and UV–vis absorption spectroscopy. The catalysts exhibit high and stable photocatalytic activity for the degradation of organic pollutants demonstrated using rhodamine B and methyl orange dyes under solar light irradiation. We show that the incorporation of the AuNPs with the Bi2S3 particles increases the photocatalytic activity 1.2 to 3-fold. Radical trapping analysis indicates that the production of hydroxyl and superoxide radicals are the dominant active species responsible for the photodegradation activity. The photocatalysts exhibit good stability and recyclability.

Keywords:
Bi2S3, nanoflower, nanorod, photocatalysis, heterostructures, AuNPs

Abstract:
Corrosion inhibition performances and adsorption behaviour at the aluminum-HCl solution interface were
investigated for reduced graphene oxide nanosheets (rGONS), tetrakis-[4,4
-((4-(benzo[d]thiazol-2-yl)-
1,2-bis(phenoxy)] (diphthalocyaninato gallium (III) chloride) (2) and tetrakis-4-(hexadecane-1,2-dioxyl)-
bis(phthalocyaninato gallium(III) chloride) (1). Corrosion inhibition effects of rGONS, 1 and 2 were evaluated alone and in combination in 1.0 M hydrochloric acid solution using electrochemical techniques. The
mechanism of aluminum corrosion inhibition revealed predominantly anodic character for rGONS and
predominantly cathodic character for 1, 2, and conjugates with rGONS . The polarization technique gave
inhibition efficiency values of 96.5% and 96.9% respectively for 1 and 2, which increased in the presence
of rGONS to 97.4% and 98.1%, respectively, for the highest concentrations of 1 and 2. Scanning electron
microscopy revealed effective metal surface protection by the inhibitors by formation of protective films

Abstract:
Nanonail shaped ZnS-CuS-Bi three component nanoparticles are synthesized via a simple one-pot colloidal
synthesis route by thermal decomposition of metal-thiolate precursors. A thiol serves as the sulfur source and a
phase directing capping agent promotes selective anisotropic growth of the nanocrystals in a noncoordinating
solvent. After the nucleation and growth of a CuS rod, reactive Cu ions serve as catalytic seeds for the nucleation
and growth of ZnS and Bi at the CuS nanorod tips. Thereby the obtained ZnS-CuS-Bi nanocrystals form a chain of
two semiconductors of decreasing band gap and a metallic Bi nanoparticle. The three components absorb light in
different spectral regions enabling efficient light harvesting. Furthermore, the band edge alignment of ZnS and
CuS promote photogenerated electron funneling towards the Bi catalyst particle, which promotes charge carrier
separation, effectively channeling the catalytic activity. The photocatalytic performance is assessed at the
example of the photodegradation of the organic dye Rhodamine B, and shows excellent performance rendering
these nanonails as inexpensive, non-toxic and efficient photocatalyst to remedy environmental pollution

Abstract:
An amide mono substituted benzothiozole phthalocyanine: zinc(II) 3-(4-((3,17,23-tris(4-(benzo [d]thiazol-2-yl)
phenoxy)-9-yl)oxy) phenyl)amide phthalocyanine (NH2BzPc) was covalently linked to undoped and heteroatom
doped detonation nanodiamonds (DNDs): B@DNDs, P@DNDs, S@DNDs, N@DNDs, and S&N@DNDs There is a
drastic decrease in highest occupied molecular orbital (HOMO) – lowest unoccupied molecular orbital (LUMO)
energy gaps for nanoconjugates compared to DNDs alone. B@DNDs-NH2BzPc, S&N@DNDs-NH2BzPc, and
P@DNDs-NH2BzPc showed superior photodynamic therapy (PDT) effects. DNDs-NH2BzPc also had a small
HOMO-LUMO gap, but did not show improved PDT activity compared to the Pc alone, suggesting doping of
DNDs is important. This study shows improved PDT effect on Michigan Cancer Foundation-7 breast cancer lines
at 7.63%, 7.62% and 6.5% cell viability for P@DNDs-NH2BzPc, S&N@DNDs-NH2BzPc and B@DNDs-NH2BzPc,
respectively

Abstract:
In the study, metabolites of Euphorbia sanguinea were used as benign reducing and stabilizing agents to obtain zinc oxide
nanoparticles (ZnO-NPs). The nanoparticles were evaluated as dual agent for photodegradation of Malachite green dye and
tyrosinase inhibitior of mushroom tyrosine enzyme. Surface plasmon bands and energy band gaps of the ZnO-NPs were
within the range 356–378 nm and 2.72–4.37 eV respectively as obtained from the UV–Vis spectra. SEM/EDS elemental
mapping of the nanoparticles gave flower-like shape and even distribution of zinc and oxygen. XRD result revealed crystallographic
peaks assigned to hexagonal phase of zinc oxide. The metal oxide nanoparticles were used to achieve 53% percentage
degradation of Malachite green dye solution in less than a minute of solar radiation, which increased to 92% in 60 min.
A first order kinetics with correlation coefficient R2
of 0.937, rate constant of 0.0084 min−1 and half-life of 82.52 min was
established for the photodegradation process. The ZnONPs exhibited good tyrosinase inhibition with IC50 of 49.016 μg/ml.
The mode of enzymatic inhibition was competitive with an inhibition constant (Ki) of 0.525 mM using Lineweaver–Burk
kinetic model.

Abstract:
Fatty acid profile of Canarium schweinfurthii mesocarp oil was determined by GC-MS.
Sulphonated fatliquor was synthesized from the oil and characterized by FT-IR, 1
H NMR,
13C NMR, and DSC. The fatliquor was applied onto light leather in the processing of
leather shoe upper and physical tests carried out on the fixed leather. The sulphonated C.
schweinfurthii mesocarp oil had good characteristics as a leather fatliquor as shown by
the physical and strength properties of the fatliquored leather. In addition, a significantly
opened up structure of the leather treated with the prepared sulphonated oil was observed
as indicated from the Scanning Electron Microscopy (SEM) images. The features of the
processed trial leathers were comparable with similar leather made with commercially
available fatliquor

Keywords:
, , , ,

Abstract:
hree different phthalocyanine complexes substituted with carbazoles were conjugated to graphene quantum dots (GQDs) through π–π stacking. The morphologies, sizes, and crystallinities of the nanoconjugates were determined using Raman spectroscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, and X-ray diffraction. The nonlinear optical (NLO) properties of the metallophthalocyanines alone and when conjugated to the GQD nanomaterial in different solvents, as well as after having been embedded in thin films, were studied. The effects of the different substituents and solvents on the NLO properties of the metallophthalocyanines were evaluated. Enhancements in the photophysical properties of the complexes upon conjugation with the nanomaterial were observed. Fluorescence quantum yields, fluorescence lifetimes, triplet quantum yields, and triplet lifetimes were measured for the complexes, and for their conjugates in DMSO.

Abstract:
Cyclic voltammetry and potentiodynamic polarization techniques were used to study the effects of 4-[4-(1,3-benzothiazol-
2yl)phenoxy] phthalonitrile (BT) and tetrakis[(benzo[d]thiazol-2ylphenoxy) phthalocyaninato] gallium(III)chloride
(ClGaBTPc) as aluminium corrosion inhibitors in 1.0 M hydrochloric acid. The presence of the inhibitors in the concentration
range of 2 to 10 μM was found to retard the aluminium corrosion process such that the inhibition efficiency was found to range
from 28.2 to 76.1%for BTand from 71.5 to 82.7%for ClGaBTPc. The latter was a better inhibitor. Scanning electronmicroscopy
and energy-dispersive X-ray measurements reveal effective metal surface protection by the inhibitors, most probably by shielding
it from the corrosion attacks of Cl− from the acid. The calculated quantum chemical parameters agreed with experimental results

Abstract:
This study describes the adsorption behavior of organic inhibitors at the aluminum-HCl
solution interface and their corrosion inhibition performance. The organic inhibitors employed are:
4-(benzo [d]thiazol-2ylthio)phthalonitrile (BTThio) and tetrakis[(benzo[d]thiazol-2-yl-thio)phthalocyaninato]
gallium(III) chloride (ClGaBTThioPc). The corrosion behavior of these inhibitors is
investigated using electrochemical and computational techniques. Open circuit potential results
reveal predominant cathodic character for the mechanism of aluminum corrosion inhibition by the
inhibitors. Inhibition efficiency values from potentiodynamic polarization measurements increase
from 46.9 to 70.8% for BTThio and 59.7 to 81.0% for ClGaBTThioPc within the concentration range of
2 to 10 M. Scanning electron microscopy (SEM) measurements reveal protection of the metal surface
from acid attack, in the presence of the inhibitors and energy dispersive X-ray (EDX) measurements
show that the most probable way by which the inhibitors protect the metal surface would be
by shielding it from the corrosion attacks of Cl

Abstract:
This work reports on the linkage of 2(3),9(10),16(17),23(24) tetrakis [(benzo[d]thiazol-2-yl phenoxy) phthalocyaninato] zinc(II) (1) and indium(III) chloride (2) to gold speckled silica (GSS) nanoparticles via gold to
sulphur (Au-S) and gold to nitrogen (Au-N) self-assembly to form the conjugates: 1-GSS and 2-GSS. The formed
conjugates were characterized using microscopic and spectroscopic techniques, and the photophysicochemical
properties and photodynamic therapy (PDT) activity against human breast adenocarcinoma cell line (MCF-7
cells) were studied. The conjugates afforded decrease in fluorescence quantum yields with corresponding increase in triplet and singlet oxygen quantum yields when compared to phthalocyanines alone. Singlet oxygen is
cytotoxic to cancer cells hence it is important for PDT. The in vitro dark toxicity of complex 2 and 2-GSS against
MCF–7 cells showed ≥93% viable cells within concentration ranges of 10–160 μg/mL. 2–GSS showed enhanced
PDT activity with less than 50% viable cells at 80 μg/mL as compared to 2 and GSS alone which showed > 60%
viable cells within 10–160 μg/mL. The observed improvements in the PDT activity of 2-GSS could be attributed
to the high singlet oxygen generation of 2-GSS compared to 2 alone in addition to the phototoxicity of GSS.

Abstract:
Benzothiazole moiety has gained a lot of attention because of its importance as essential pharmacophore in the development of metal based drugs. Nickel(II) and copper(II) complexes of a benzothiazole based ligand, 2,2’-bibenzo[d]thiazole (L1), synthesized by the reaction of benzothiazole-2-carbonylchloride and o-aminothiophenol, is reported. The compounds were characterised by elemental and percentage metal analyses, spectroscopic (FTIR and UV–vis), 1H and 13C NMR, Mass spectra, thermal, magnetic moment and molar conductance analyses. The mass spectra, elemental and percentage metal composition of the metal complexes gave a 2:1 ligand to metal stoichiometric mole ratio. The spectral data showed that the ligand was coordinated to the metal ions through the nitrogen atoms of the benzothiazole moiety. The electronic spectra and magnetic susceptibility measurements showed that the nickel and copper complexes adopted square planar geometries. The ligand and its metal(II) complexes were screened against some drug resistant microbes and were found to exhibit varied degree of antimicrobial activities. The nickel complex was more active compared to ciprofloxacin against Staphylococcus aureus and Bacillus cereus. Similarly, the antioxidant potential of the ligand was evaluated. The ligand is a better ferrous ion chelating agent compared to 1,10-phenanthroline and 2,2-bipyridine. The ligand and its complexes exhibited good antimicrobial and Fe2+ chelating properties making them probable compounds of interest in antibiotic and antioxidant drug researches.

Abstract:
The synthesis and characterization of a series of 3,5-di-p
-benzyloxystyrylBODIPY dyes with different substituents at the meso-aryl position is reported. The photophysical and nonlinear optical properties are described. BODIPYs of this type are found to be suitable for optical limiting at 532 nm on the nanosecond timescale. An enhancement of the population of the T1
state through the incorporation of bromine atoms at the 2,6-positions does not result in an enhancement of the optical limiting properties on a nanosecond timescale. This suggests that, in contrast with phthalocyanines, access to excited state absorption (ESA) from the T1
state through the introduction of a heavy atom effect does not provide a significantly improved reverse saturable absorbance response compared to ESA from the S1
state.

Abstract:
The synthesis, photophysicochemical and photodynamic therapy (PDT) activity of quaternary benzothiazole substituted zinc phthalocyanine (2, containing two charges, and 3, containing four charges) are reported in this work. Furthermore, the activity of the synthesized complex was compared to non-quaternary derivative (1). Higher triplet and singlet oxygen quantum yields of 0.92 and 0.85, respectively, for quaternized complexes 2 and 3 compared to complex 1 alone. Complexes 1, 2 and 3 showed relatively no dark toxicity against the epithelial breast cancer cells with cell survival of above 90 ± 3%. The quaternary derivatives (2 and 3) showed superior PDT activity with 30% or less of viable cells at concentration of 50.0 μg/mL in comparison to complex 1 alone which further lay credence to the importance of quaternization in the enhancement of PDT activit

Abstract:
In this work, we report on the synthesis of tris-[(2,2,7,7-tetramethyltetrahydro-3aH-bis([1,3]dioxolo)[4,5-b:4′,5′-d]pyran-5-yl)methoxy)-2-(4-benzo[d]thiazol-2-ylphenoxyphthalocyaninato] zinc(II) (complex 3) and its linkage to gold nanoparticles (AuNPs) of different shapes through S-Au/N-Au self-assembly. The conjugates of complex 3 (with both gold nanorods (AuNR) and nanospheres (AuNS)), displayed decreased fluorescence quantum yield with corresponding improved triplet and singlet quantum yields compared to complex 3 alone, however 3-AuNR showed improved properties than 3-AuNS. Complex 3 showed relatively low in vitro dark cytotoxicity against the epithelial breast cancer cells with cell survival ≥ 85% at concentration ≤ 160 μg/mL but afforded reduced photodynamic therapy activity which may be due to aggregation. 3-AuNR afforded superior PDT activity with <50% viable cells at concentration ≥ 40 μg/mL in comparison to 3-AuNS with <50% viable cells at concentration ≥ 80 μg/mL. The superior activity of 3-AuNR is attributed to the photothermal therapy effect since nanorods absorb more light at 680 nm than nanospheres

Abstract:
The synthesis of a novel asymmetric phthalocyanine, (4-(4-(benzo[d]thiazol-2-yl)phenoxy)-2,10,17-tris(4-(2-carboxyethyl)phenoxy)phthalocyaninatol)zinc(II), complex 3, is reported. Complex 3 together with the previously reported complexes tetrakis[(benzo[d]thiazol-2-yl phenoxy)phthalocyaninato]zinc(II) (4) and 3-(4-((3,17,23-tris(4-(benzo[d]thiazol-2-yl)phenoxy)phthalocyaninatol)oxy)phenyl)propanoic acid zinc(II) (5), were linked to gold nanotriangles (AuNTs) through S–Au/Au–N self-assembly to afford the conjugates (3-AuNTs, 4-AuNTs and 5-AuNTs). The photophysicochemical behaviour of the complexes and their conjugates were studied. The asymmetric complexes 3 and 5, displayed improved triplet and singlet oxygen quantum yields compared to the symmetric complex 4, while all conjugates displayed improved triplet and singlet oxygen quantum yields compared to their respective complexes alone. The complexes and their conjugates could serve as good candidates for photodynamic therapy.

Abstract:
Beside different methods and materials used to develop electrochemical sensors, the modification of the electrode using click reaction based on metallophthalocyanine (MPc) compounds are shown to improve the stability and sensitivity of the sensor. This work reported the development of electrochemical sensor for mercury (II), Lead (II), copper (II) and cadmium (II) ions detection based on the synthesized novel low symmetry alkyne terminated cobalt Phthalocyanine (CoPc) derivative. Differential pulse stripping voltammetry (DPSV) technique was employed for the first time in simultaneous determination of trace levels of the above metal ions using modified glassy carbon electrode (GCE) via click chemistry. Under the optimum experimental conditions, the anodic peak current is proportional to the concentrations of metal ions over a wide range of 0 to 0.1 mM with nanolevel detection limit of 81.94, 327.71, 55.87 and 347.06 nM and the sensitivity of 866.23 ± 5.48, 215.82 ± 2.16, 1979.48 ± 11.47 and 204.50 ± 1.10 μA/mM for Hg(II), Cu(II), Pb(II) and Cd(II), respectively. The selectivity of the clicked-CoPc modified GCE toward Hg(II), Cu(II), Pb(II), Cd(II) present no interference from these metals ions. The fabricated electrochemical sensor exhibited very good electrochemical properties such as good reproducibility, stability, reusability and is suitable for the detection of heavy metal ions in tap water in our laboratory.

Abstract:
The syntheses of neodymium(III) 2,9,16,23-tetrakis-(2,6-di-tert-butyl-4-methylphenoxy)phthalocyanine (2),
bis europium(III) 2,9,16,23-tetrakis-(2,6-di-tert-butyl-4-methylphenoxy)phthalocyanine (3), bis dysprosium(III)
2,9,16,23-tetrakis-(2,6-di-tert-butyl-4-methylphenoxy)phthalocyanine (4) and their conjugated analogues with
nitrogen doped quantum dots (NGQDs) are reported herein. The optical nonlinearity of the sandwich-type phthalocyanine complexes and their conjugates with NGQDs were studied in dimethyl sulfoxide using the
open aperture Z-scan technique at an excitation wavelength of 532 nm with a 10 ns pulse. The nonlinear
absorption coefficient (beff) value of the samples ranges from 15 cm GW1 to 89.6 cm GW1
. Complex 4 and
its conjugates afforded a strong optical limiting behaviour compared to the other samples. These fabricated
complexes and their conjugates with NGQDs could serve as a plausible nonlinear optical (NLO) material due
to their fascinating NLO properties

Abstract:
The nonlinear optical behaviors of ball-type phthalocyanine complexes: 10,11,’150,250-tetrakis-[4,40-((4-
formyl-1,2-bisphenoxyl))bis(phthalocyaninato zinc (II)] (5), 10,11,’150,250-tetrakis-[4,40-((4-formyl-1,2-
bisphenoxyl) bis(phthalocyaninato gallium (III) chloride)] (6), and 10, 11,’150,250-tetrakis-4,40-((4-formyl-
1,2-phenoxyl)bis(phthalocyaninato indium (III) chloride)] (7) and the corresponding monomeric
derivatives 8–10 were investigated using nanosecond pulse open aperture Z-scan technique at
532 nm. The nonlinear response showed strong reverse saturable absorption for all the complexes both in
solution and when embedded in polymer matrix. The dimeric complexes showed better optical limiting
properties compared to the monomeric derivatives. The beff values for the dimeric complexes 5–7 were
found to be 48.5, 55.2, and 60.1 cm/GW for 5, 6A, and 7 respectively, higher than the corresponding
monomeric derivatives 8–10. Enhanced optical limiting properties were observed when the complexes
were formulated in thin
films. The second order hyperpolarizability values were in order of 1028–
1026 esu in solution and 1027–1026 in
films.

Abstract:
The synthesis of asymmetric benzothiazole substituted phthalocyanines (complexes 3 to 5) and their covalent
attachment to glutathione (GSH) functionalized quantum dots (QDs) are reported in this work. Additionally,
their photophysical and nonlinear optical properties were investigated. A decrease in the fluorescence quantum
yield with corresponding increase in the triplet quantum yield was observed when the complexes were covalently
linked to glutathione (GSH) functionalized cadmiumtelluride (CdTe) quantumdots. Reverse saturable absorptionwas
found to be predominantly dominated by excited state absorption. The observed limiting threshold
values range from 0.29–0.75 J/cm2.

Abstract:
The synthesis of 4-bis(4-aminophenoxy)phenoxy derivatized phthalocyanine containing In (complex 2), and Ga
(complex 3), and the previously reported complex 4 (containing Zn) and their covalent attachment to glutathione
(GSH) functionalized cadmium telluride quantum dots (CdTe QDs) are reported in this work.
Additionally, their photophysical, energy transfer and nonlinear optical properties were investigated. The
covalently linked derivatives showed lower fluorescence quantum yields with corresponding higher triplet
quantum yields. Quenching of the photoluminescence intensity of the CdTe QDs was observed to be due to
energy transfer from the QDs to phthalocyanine (Pcs) molecules. The reverse saturable absorption nonlinear
optical response was found to be predominantly dependent on the excited state absorption. The observed limiting
threshold ranges from 0.04 to 0.62 J/cm−2.

Abstract:
The synthesis of ball-type zinc and gallium phthalocyanines (complexes 2 and 3) and their covalent linkage to glutathione
(GSH) and amine functionalized quantum dots (QDs) are reported in this work. Furthermore, their photophysical, photoinduced
resonance energy transfer and optical limiting response were investigated. We observed a decrease in the
fluorescence quantum yield with corresponding increase in the triplet quantum yield of the nanoconjugates in comparison
to the phthalocyanine complexes alone. The reverse saturable absorption was found to be dependent on excited state
absorption and the observed limiting threshold ranged from 0.32 to 1.43 J/cm2. Enhanced triplet parameters and
nonlinear optical performance was found when the complexes were covalently linked to semiconductor quantum dots
compared to carbon based graphene quantum dots.

Abstract:
The syntheses of zinc(II) tetra–[3–(4–phenoxy) (propanoic acid) phthalocyanine] (2) and zinc(II) mono–[3–(4–phenoxy) (propanoic acid) phthalocyanine (3) are reported in this work. Compounds 2 and 3 were covalently linked to glutathione capped silver (AgNPs–GSH), gold (AuNPs–GSH) and silver-gold alloy (Ag3Au1NPs–GSH) nanoparticles (NPs) via an amide bond formation to afford the conjugates: 2–AgNPs–GSH, 3–AgNPs–GSH, 2–AuNPs–GSH, 3–AuNPs–GSH, 2-Ag3Au1NPs–GSH and 3-Ag3Au1NPs–GSH. The photophysicochemical behaviours of the compounds and their conjugates with NPs were assessed in solution. The conjugates afforded a decrease in fluorescence quantum yields and lifetimes with improved triplet quantum yields in comparison to the compounds. Accordingly, the AgNPs and AuNPs conjugates with the compounds afforded high singlet quantum yields. On the contrary, the conjugates of the alloy afforded decreased singlet quantum yields probably due to the screening effect. The compounds and their conjugates with NPs could serve as a viable and efficacious photosensitizer for photodynamic therapy.

Abstract:
In this study, the photophysical, nonlinear absorption and nonlinear optical limiting properties of zinc and gallium phthalocyanine complexes: tetrakis[(benzo[d]thiazol-2-yl phenoxy)phthalocyaninato]zinc(II) (3), tetrakis[(benzo[d]thiazol-2-yl phenoxy)phthalocyaninato] gallium(III) chloride (4), tetrakis[(benzo[d]thiazol-2-ylthio)phthalocyaninato] zinc(II) (5), tetrakis[(benzo[d]thiazol-2-ylthio)phthalocyaninato] gallium(III) chloride (6), were investigated both in solution and when embedded in polystyrene thin films using 532 nm laser excitation at 10 ns pulses. It was also observed that complexes that have higher triplet state absorption also possessed enhanced nonlinear and optical limiting behavior. Superior optical performance was observed when the complexes were embedded in thin films compared to when they are in solution. Complex 6 in thin films gave the highest imaginary third-order susceptibility (Im
[X(3)]) and hyperpolarizability (γ) at 4.61 × 10-7
esu and 3.44 × 10-26 esu, respectively, with a low Ilim value of 0.06 J.cm-2

Abstract:
n this study, the photophysical, nonlinear absorption and nonlinear optical limiting properties of 4-(2,4-bis(4-aminophenoxy)phenoxy) phthalocyinato zinc(II) phthalocyanine (6) conjugated to metallic nanoparticles have been investigated using open aperture Z-scan techniques using 532 nm nanosecond pulses. The nonlinear optical response demonstrated that the studied complex and the nanoconjugates exhibit higher excited state absorption cross-section compared to ground state absorption. Enhanced optical limiting performance was observed when complex 6 was conjugated to nanoparticles with 6CB-AuNPs (CB = covalent bond) showing the highest optical limiting threshold of 0.36 J cm−2.

Abstract:
In this study, the photophysical, and nonlinear optical limiting properties of low symmetry tris[(4-benzo[d] thiazol-2-ylphenoxy)-2-phenoxyl acetic acid phthalocyaninato] zinc (II) (3) conjugated to metallic nanoparticles have been investigated using open aperture Z-scan techniques at 532 nm. The nonlinear optical response demonstrated that the studied complex and the nanoconjugates exhibits higher excited state absorption cross-section resulting from S1 and T1 compared to ground state absorption. Enhanced optical limiting performance was observed when the complex was conjugated to nanoparticles with 3SA-AuNPs showing the best optical limiting threshold of 0.39 J/cm2.

Abstract:
Benzothiazole phthalocynines complexes: tetrakis[(benzo[d]thiazol-2-ylphenoxy)phthalocyaninato] indium(III) chloride (1) and tetrakis[(benzo[d]thiazol-2-ylthio)phthalocyaninato] indium(III) chloride (2) were synthesisized and their nanosecond nonlinear optical behaviours in solution, solid state and when conjugated to metallic nanoparticles were examined and compared to those of the corresponding ZnPc and GaPc which are designated as: tetrakis[(4-benzo[d]thiazol-2-ylphenoxy)phthalocyaninato] zinc(II) (3), tetrakis[(4-benzo[d]thiazol-2-ylphenoxy)phthalocyaninato] gallium(III) chloride (4), tetrakis[(4-benzo[d]thiazol-2-ylthio)phthalocyaninato] zinc(II) (5) and tetrakis[(4-benzo[d]thiazol-2-ylthio)phthalocyaninato] gallium(III) chloride (6). Trends in the electronic structures were identified through a comparison of the UV–vis absorption and magnetic circular dichroism (MCD) spectroscopy of the complexes and calculated spectra predicted by time dependent density functional theory (TD-DFT). Of all the complexes and nanoconjugates, complex 2 (containing sulphur linkages and In as a central metal) gave the best optical limiting behaviour.

Abstract:
In this study, we report on the enhanced nonlinear optical properties of novel tetrakis-4-(hexadecane-1,2-dioxyl)-bis(phthalocyaninato zinc(II)) (4), tetrakis-4-(hexadecane-1,2-dioxyl)-bis(phthalocyaninato gallium chloride) (5) and tetrakis-4-(hexadecane-1,2-dioxyl)-bis(phthalocyaninato indium chloride) (6) both in solution and when embedded in polymer thin films. Complexes 5 and 6 bearing heavy atoms showed enhanced triplet quantum yield and nonlinear optical response. The nonlinear third-order susceptibility and second-order hyperpolarizability values are also reported. Time dependent density functional theory (TD-DFT) calculations were performed in order to explain the origin of the observed UV-vis and magnetic circular dichroism (MCD) spectra of the complexes.

Abstract:
The synthesis of ball–type indium phthalocyanine (complex 4) and its covalent attachment to glutathione (GSH–) capped (Ag, Au, CdTeSe, CdTeSe/ZnO) nanoparticles are reported in this work. Furthermore, their photophysical and nonlinear optical behaviour were investigated. We observed a decrease in the fluorescence quantum yield with corresponding increase in the triplet quantum yield of the nanoconjugates in comparison to complex 4 alone. The reverse saturable absorption was found to be dependent on excited state absorption. The optical limiting threshold ranges from 0.40–0.78 (J/cm2). The nanoconjugate of the complex 4 with GSH–CdTeSe/ZnO (QD1) accounted for the most improved triplet state parameters and nonlinear optical behaviour in comparison to complex 4 and the other nanoconjugates studied in this work.