Modulation of the tumor microenvironment and mechanism of immunotherapy-based drug resistance in breast cancer

Breast cancer, the most frequent female malignancy, is often curable when detected at an early stage. The treatment of metastatic breast cancer is more challenging and may be unresponsive to conventional therapy. Immunotherapy is crucial for treating metastatic breast cancer, but its resistance is a major limitation. The tumor microenvironment (TME) is vital in modulating the immunotherapy response. Various tumor microenvironmental components, such as cancer-associated fibroblasts (CAFs), tumor-associated macrophages (TAMs), and myeloid-derived suppressor cells (MDSCs), are involved in TME modulation to cause immunotherapy resistance. This review highlights the role of stromal cells in modulating the breast tumor microenvironment, including the involvement of CAF-TAM interaction, alteration of tumor metabolism leading to immunotherapy failure, and other latest strategies, including high throughput genomic screening, single-cell and spatial omics techniques for identifying tumor immune genes regulating immunotherapy response. This review emphasizes the therapeutic approach to overcome breast cancer immune resistance through CAF reprogramming, modulation of TAM polarization, tumor metabolism, and genomic alterations.

1,1'-Bis-(diphenylphosphino)ferrocene appended d8- and d10-configuration based thiosquarates: the molecular and electronic configurational insights into their sensitization and co-sensitization properties for dye sensitized solar cells

Three new d8- and d10-configuration based 1,1'-bis-(diphenylphosphino)ferrocene (dppf) appended thiosquarates complexes with general composition [M(mtsq)2dppf] (M = Ni2+ (NiL2); Zn2+ (ZnL2) and Cd2+ (CdL2)) (mtsq = 3-ethoxycyclobutenedione-4-thiolate) have been synthesized and characterized spectroscopically as well as in case of NiL2 by single crystal X-ray diffraction technique. The single crystal X-ray analysis reveals square planar geometry around Ni(II) in NiL2, where Ni(II) coordinates with two sulfur centres of two mtsq ligands in monodentate fashion and two phosphorus of a dppf ligand in chelating mode. The supramolecular architecture of NiL2 is sustained by intermolecular C-H⋯O interactions to form one-dimensional chain. Further, the application of these newly synthesized complexes as sensitizers and co-sensitizers/co-absorbents with ruthenium based N719 sensitizer in dye-sensitized solar cells (DSSCs) have been explored. The DSSC set-up based on NiL2 offers best photovoltaic performance with photovoltaic efficiency (η) 5.12%, short-circuit current (Jsc) 11.60 mA cm-2, open circuit potential (Voc) 0.690 V and incident photon to current conversion efficiency (IPCE) 63%. In co-sensitized DSSC set-up, ZnL2 along with state-of-the-art N719 dye displays best photovoltaic performance with η 6.65%, Jsc 14.47 mA cm-2, Voc 0.729 V and IPCE 69%, thereby showing an improvement by 15.25% in photovoltaic efficiency in comparison to the photovoltaic efficiency of N719 sensitized DSSC set-up. Variation in co-sensitization behaviour have been ascribed to the differences in the excited state energy level of co-sensitizers. The ZnL2 and CdL2 have a higher energy level position than N719 dye, allowing efficient electron transfer to N719 during light irradiation, while excited state of NiL2 is lower than N719 dye, preventing photoexcited electron transfer to N719, resulting in its lowest overall efficiency among the three co-sensitized DSSC setups.

Microbial production of N-acetyl-D-glucosamine (GlcNAc) for versatile applications: Biotechnological strategies for green process development

N-acetyl-d-glucosamine (GlcNAc) is a commercially important amino sugar for its wide range of applications in pharmaceutical, food, cosmetics and biofuel industries. In nature, GlcNAc is polymerised into chitin biopolymer, which is one of the major constituents of fungal cell wall and outer shells of crustaceans. Sea food processing industries generate a large volume of chitin as biopolymeric waste. Because of its high abundance, chitinaceous shellfish wastes have been exploited as one of the major precursor substrates of GlcNAc production, both in chemical and enzymatic means. Nevertheless, the current process of GlcNAc extraction from shellfish wastes generates poor turnover and attracts environmental hazards. Moreover, GlcNAc isolated from shellfish could not be prescribed to certain groups of people because of the allergic nature of shell components. Therefore, an alternative route of GlcNAc production is advocated. With the advancement of metabolic construction and synthetic biology, microbial synthesis of GlcNAc is gaining much attention nowadays. Several new and cutting-edge technologies like substrate co-utilization strategy, promoter engineering, and CRISPR interference system were proposed in this fascinating area. The study would put forward the potential application of microbial engineering in the production of important pharmaceuticals. Very recently, autotrophic fermentation of GlcNAc synthesis has been proposed. The metabolic engineering approaches would offer great promise to mitigate the issues of low yield and high production cost, which are major challenges in microbial bio-processes industries. Further process optimization, optimising metabolic flux, and efficient recovery of GlcNAc from culture broth, should be investigated in order to achieve a high product titer. The current study presents a comprehensive review on microbe-based eco-friendly green methods that would pave the way towards the development of future research directions in this field for the designing of a cost-effective fermentation process on an industrial setup.

Alkaline hydrolysis of spent aromatic biomass for production of phenolic aldehydes, lignin, and cellulose

In order to combat the environmental issues associated with the burning of spent aromatic biomass (SAB), a method for alkaline hydrolysis of SAB has been developed to afford phenolic acids, predominantly the p-coumaric acid, lignin, and cellulose. Lignin (∼15 wt%) from alkaline hydrolysate was separated by precipitation while a mixture of phenolic acids obtained was directly reacted with a green reagent, PhI(OAc)2, under one-pot condition to afford a mixture of p-hydroxybenzaldehyde (>90 wt%) and vanillin (<10 wt%). Unreacted biomass obtained in the process was successfully used as a substrate for the production of cellulose (∼40 wt%). The developed method exhibits potential for application on an industrial scale.

Therapeutic implications of cancer stem cells in prostate cancer

Prostate cancer, one of the most frequently occurring cancers in men, is a heterogeneous disease involving multiple cell types within tumors. This tumor heterogeneity at least partly results from genomic instability leading to sub-clonal cellular differentiation. The differentiated cell populations originate from a small subset of cells with tumor-initiating and stem-like properties. These cells, termed prostate cancer stem cells (PCSCs), play crucial roles in disease progression, drug resistance, and relapse. This review discusses the origin, hierarchy, and plasticity of PCSCs; methods for isolation and enrichment of PCSCs; and various cellular and metabolic signaling pathways involved in PCSC induction and maintenance, as well as therapeutic targeting.

Copper(ii) and cobalt(iii) Schiff base complexes with hydroxy anchors as sensitizers in dye-sensitized solar cells (DSSCs)

Two Schiff base complexes of copper(ii) and cobalt(iii) having the formulae [CuL₂] (Cu-Sal) and [CoL₃] (Co-Sal) (HL = 2-(((2-hydroxyethyl)imino)methyl)phenol) have been synthesized and characterized microanalytically, spectroscopically and in the case of Cu-Sal using single crystal X-ray diffraction technique. The single crystal X-ray analysis reveals a square planar geometry around Cu(ii) satisfied by phenoxide oxygen and imine nitrogen of the L^- ligand to generate a six membered chelate ring. The solid state structure of Cu-Sal is satisfied by varied intermolecular non-covalent interactions. The nature of these interactions has been addressed with the aid of Hirshfeld surface analysis. Both compounds have been used as sensitizers in TiO₂ based dye sensitized solar cells (DSSCs) and the DSSC experiments revealed that Co-Sal offers better photovoltaic performance in comparison to Cu-Sal. The Co-Sal exhibited a J _sc of 9.75 mA cm^-2 with a V _oc of -0.648 V, incident photon to current conversion efficiency (IPCE) of 57% and η of 3.84%. The relatively better photovoltaic performance of Co-Sal could be attributed to better light absorption and dye loading than that of Cu-Sal.

A double co-sensitization strategy using heteroleptic transition metal ferrocenyl dithiocarbamate phenanthrolene-dione for enhancing the performance of N719-based DSSCs

Three new heteroleptic dithiocarbamate complexes with formula [M(Phen-dione)(Fcdtc)]PF₆ (where M = Ni(ii) Ni-Fc, Cu(ii) Cu-Fc) and [Co(Phen-dione)(Fcdtc)₂]PF₆ (Co-Fc) (Fcdtc = N-ethanol-N-methylferrocene dithiocarbamate and Phen-dione = 1,10-phenanthroline-5,6-dione; PF₆ ^- = hexafluorophosphate) were synthesized and characterized using microanalysis, FTIR, electronic absorption spectroscopy and mass spectrometry. The solution state electronic absorption spectroscopy for all three complexes displayed a band at ∼430 nm corresponding to the ferrocene unit and another low-intensity band in the visible region arising because of the d-d transitions. These newly synthesized complexes were used as co-sensitizers for the state-of-the-art di-tetrabutylammonium cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)ruthenium(ii) (N719) dye in dye-sensitized solar cells (DSSCs). Among the three co-sensitizers/co-adsorbent-based DSSC set-ups, the assembly fabricated using Co-Fc/N719 displayed good photovoltaic performance with 5.31% efficiency (η) while a new triple component strategy inculcating N719, Co-Fc and Cu-Fc dyes offered the best photovoltaic performance with 6.05% efficiency (η) with incident photon to current conversion efficiency (IPCE) of 63%. This indicated an upliftment of the DSSC performance by ∼38% in comparison to the set-up constructed by employing only N719 dye (η = 4.39%) under similar experimental conditions.

Efficient solar light-driven hydrogen generation using an Sn3O4 nanoflake/graphene nanoheterostructure

Herein, we report Sn₃O₄ and Sn₃O₄ nanoflake/graphene for photocatalytic hydrogen generation from H₂O and H₂S under natural “sunlight” irradiation. The Sn₃O₄/graphene composites were prepared by a simple hydrothermal method at relatively low temperatures (150 °C). The incorporation of graphene in Sn₃O₄ exhibits remarkable improvement in solar light absorption, with improved photoinduced charge separation due to formation of the heterostructure. The highest photocatalytic hydrogen production rate for the Sn₃O₄/graphene nanoheterostructure was observed as 4687 μmol h⁻¹ g⁻¹ from H₂O and 7887 μmol h⁻¹ g⁻¹ from H₂S under natural sunlight. The observed hydrogen evolution is much higher than that for pure Sn₃O₄ (5.7 times that from H₂O, and 2.2 times from H₂S). The improved photocatalytic activity is due to the presence of graphene, which acts as an electron collector and transporter in the heterostructure. More significantly, the Sn₃O₄ nanoflakes are uniformly and parallel grown on the graphene surface, which accelerates the fast transport of electrons due to the short diffusion distance. Such a unique morphology for the Sn₃O₄ along with the graphene provides more adsorption sites, which are effective for photocatalytic reactions under solar light. This work suggests an effective strategy towards designing the surfaces of various oxides with graphene nanoheterostructures for high performance of energy-conversion devices.

Herein, we have demonstrated the synthesis of the two-dimensional hierarchical Sn₃O₄/graphene nanostructure by a facile solvothermal method. The nanostructure has been used as a photocatalyst for hydrogen production under solar light.

Synergetic Strategy for the Fabrication of Self-Standing Distorted Carbon Nanofibers with Heteroatom Doping for Sodium-Ion Batteries

Currently, the limited availability of lithium sources is escalating the cost of lithium-ion batteries (LIBs). Considering the fluctuating economics of LIBs, sodium-ion batteries (SIBs) have now drawn attention because sodium is an earth-abundant, low-cost element that exhibits similar chemistry to that of LIBs. Despite developments in different anode materials, there still remain several challenges in SIBs, including lighter cell design for SIBs. The presented work designs a facile strategy to prepare nitrogen-doped free-standing pseudo-graphitic nanofibers via electrospinning. A structural and morphological study implies highly disordered graphitic structured nanofibers having diameters of ∼120-170 nm, with a smooth surface. X-ray photoelectron spectroscopy analysis showed that nitrogen was successfully doped in carbon nanofibers (CNFs). When served as an anode material for SIBs, the resultant material exhibits excellent sodium-ion storage properties in terms of long-term cycling stability and high rate capability. Notably, a binder-free self-standing CNF without a current collector was used as an anode for SIBs that delivered capacities of 210 and 87 mA h g-1 at 20 and 1600 mA g-1, respectively, retaining a capacity of 177 mA h g-1 when retained at 20 mA g-1. The as-synthesized CNFs demonstrate a long cycle life with a relatively high Columbic efficiency of 98.6% for the 900th cycle, with a stable and excellent rate capacity. The sodium storage mechanisms of the CNFs were examined with various nitrogen concentrations and carbonization temperatures. Furthermore, the diffusion coefficients of the sodium ions based on the electrochemical impedance spectra measurement have been calculated in the range of 10-15-10-12 cm2 s-1, revealing excellent diffusion mobility for Na atoms in the CNFs. This study demonstrates that optimum nitrogen doping and carbonization temperature demonstrated a lower Warburg coefficient and a higher Na-ion diffusion coefficient leads to enhanced stable electrochemical performance. Thus, our study shows that the nitrogen-doped CNFs will have potential for SIBs.

Cobalt-Doped Manganese Dioxide Hierarchical Nanostructures for Enhancing Pseudocapacitive Properties

Herein, overall improvement in the electrochemical performance of manganese dioxide is achieved through fine-tuning the microstructure of partially Co-doped manganese dioxide nanomaterial using facile hydrothermal method with precise control of preparative parameters. The structural investigation exhibits formation of a multiphase compound accompanied by controlled reflections of α-MnO₂ as well as γ-MnO₂ crystalline phases. The morphological examination manifests the presence of MnO₂ nanowires having a width of 70-80 nm and a length of several microns. The Co-doped manganese dioxide electrode displayed a particular capacitive behavior along with a rising order of capacitance concerning with increased cobalt ion concentration suitable for certain limits. The value of specific capacitance achieved by a 5% Co-doped manganese dioxide sample was 1050 F g^-1 at 0.5 A g^-1, which was nearly threefold greater than that achieved by a bare manganese dioxide electrode. Furthermore, Co-doped manganese dioxide nanocomposite electrode exhibits exceptional capacitance retention (92.7%) till 10,000 cycles. It shows the good cyclability as well as stability of the material. Furthermore, we have demonstrated the solid-state supercapacitor with good energy and power density.

CdS decorated MnWO4 nanorod nanoheterostructures: a new 0D-1D hybrid system for enhanced photocatalytic hydrogen production under natural sunlight

Constructing a heterostructure is an effective strategy to reduce the electron-hole recombination rate, which enhances photocatalytic activity. Here, we report a facile hydrothermal method to grow CdS nanoparticles on MnWO₄ nanorods and their photocatalytic hydrogen generation under solar light. A structural study shows the decoration of hexagonal CdS nanoparticles on monoclinic MnWO₄. Morphological studies based on FE-TEM analysis confirm the sensitization of CdS nanoparticles (10 nm) on MnWO₄ nanorods of diameter-35 nm with mean length ∼100 nm. The lower PL intensity of MnWO₄ was observed with an increasing amount of CdS nanoparticles, which shows inhibition of the charge carrier recombination rate. A CdS@MnWO₄ narrow band gap semiconductor was employed for photocatalytic hydrogen generation from water under solar light and the highest amount of hydrogen, i.e. 3218 μmol h^-1 g^-1, is obtained which is 21 times higher than that with pristine MnWO₄. The enhanced photocatalytic activity is ascribed to the formation of a CdS@MnWO₄ nanoheterostructure resulting in efficient spatial separation of photogenerated electron-hole pairs due to vacancy defects. More significantly, direct Z-scheme electron transfer from MnWO₄ to CdS is responsible for the enhanced hydrogen evolution. This work signifies that a CdS decorated MnWO₄ nanoheterostructure has the potential to improve the solar to direct fuel conversion efficiency.

Phase transformation in tungsten oxide nanoplates as a function of post-annealing temperature and its electrochemical influence on energy storage

The morphology and crystal structure of electrode materials have an enormous impact on their electrochemical properties for employment in supercapacitors for various applications. In this study, the transformations of the crystal structure of WO₃·H₂O nanoplates were conducted by post-annealing at 200 °C and 400 °C. The morphological and structural evolution of the electrodes was studied via FEG-SEM, HRTEM, FTIR, XRD, and Raman spectroscopy. The phase transition and enhanced degree of crystallinity were observed with increasing temperature. The orthorhombic structures of the hydrate WO₃·H₂O (W80), the mixed-phase with mesoporous structure (W200), and finally the monoclinic phase of WO₃ structures (W400) were achieved at annealing temperatures of 80 °C, 200 °C, and 400 °C respectively. The electrochemical performance of electrode W200 showed the highest specific capacitance of 606 F g^-1 as compared to electrode W80 (361 F g^-1), and was two-fold greater than electrode W400 (302 F g^-1) at a current density of 1 A g^-1. Moreover, electrode W200 exhibited excellent cyclic stability of 89% at an ultrahigh scan rate of 100 mV s^-1 after 4000 cycles. The results highlight that the mixed-phase WO₃ nanoplates would make a suitable electrode material for supercapacitors with desired electrochemical features.

Effects of Au loading on the enhancement of photoelectrochemical activities of the Au@ZnO nano-heteroarchitecture

The nano-heteroarchitecture of Au@ZnO evidencing the surface attachment without chemical reaction at the interface delivered enhanced PEC activities by facilitating the injection of hot electrons from the SP state into the conduction band of ZnO.

Gelatin interpenetration in poly N-isopropylacrylamide network reduces the compressive modulus of the scaffold: A property employed to mimic hepatic matrix stiffness

The progression of liver disease from normal to cirrhotic state is characterized by modulation of the stiffness of the extracellular matrix (ECM). Mimicking this modulation in vitro scaffold could provide a better insight into hepatic cell behavior. In this study, interpenetrating poly(N-isopropylacrylamide-co-gelatin) cryogels were synthesized in 48 different compositions to yield scaffolds of different properties. It was observed that a high concentration of N-isopropylacrylamide (NIPAAm) leads to the formation of small pores while gelatin interpenetration on poly-NIPAAm framework renders porous structure. Swelling properties and porosity of the gels decreased with an increase in NIPAAm concentration owing to the increased compactness of the gels. Gelatin interpenetration relaxed the gels and enhanced these properties. An increase in gelatin concentration led to a reduction in compressive moduli indicating that gelatin interpenetration in the poly-NIPAAm network softens the cryogel. With the increase in NIPAAm concentration, the effect of gelatin interpenetration in reducing the compressive moduli expanded. The cytocompatibility studies indicated that the gels are cell-adherent and compatible with HepG2. Furthermore, biochemical and real-time polymerase chain reaction studies revealed that HepG2 and Huh-7 cells cultured on scaffolds mimicking the ECM stiffness of normal liver (1.5-2.5 kPa) exhibited optimum liver-specific functionalities. Increasing the stiffness to fibrotic (4-9 kPa) and cirrhotic (10-20 kPa) ECM decreases the functionality.

Functional design of pH-responsive folate-targeted polymer-coated gold nanoparticles for drug delivery and in vivo therapy in breast cancer

BACKGROUND

Curcumin has been widely used owing to its various medicinal properties including antitumor effects. However, its clinical application is limited by its instability, poor solubility and low bioavailability. Folic acid (FA)-functionalized nanoformulations may enhance the sustained release of an anticancer drug (curcumin) by tumor-specific targeting to improve therapeutic benefit. This study aims to design a nanoconjugate (NC) comprised of folate-curcumin-loaded gold-polyvinylpyrrolidone nanoparticles (FA-CurAu-PVP NPs) for targeted delivery in breast cancer model systems.

METHODS

We developed curcumin-loaded FA-functionalized Au-PVP NCs by layer-by-layer assembly. The folic acid-curcumin Au-PVP NCs (FA-CurAu-PVP NCs) were characterized by ultraviolet-visible spectra, Fourier transform infrared spectroscopy, X-ray powder diffraction and thermogravimetric analysis. In vitro anticancer and antimigratory effects of NCs were examined by performing MTT and wound migration assays. The in vivo antitumor efficacy of NCs was investigated using a preclinical breast cancer orthotopic mouse model.

RESULTS

Curcumin (40 µg/mL) was loaded along with conjugation of folate onto Au-PVP NPs to form FA-CurAu-PVP NCs. The size and charge of the NCs were increased gradually through layer-by-layer assembly and showed 80% release of curcumin at acidic pH. The NC did not show aggregation when incubated with human serum and mimicked an intrinsic peroxidase-like property in the presence of 3,3',5,5'-tetramethylbenzidine substrate. The MTT data using these NCs showed efficient anticancer activity at lower doses in estrogen/progesterone receptor (ER/PR)-negative cells compared with ER/PR-positive cells. Furthermore, the NCs did not show cytotoxicity at the investigated concentration in human breast epithelial and mouse fibroblast cell lines. They showed inhibitory effects on cell migration and high antitumor efficacy in in vivo analysis.

CONCLUSION

These results suggest that folate-based tumor targeting using CurAu-PVP NCs is a promising approach for tumor-specific therapy of breast cancer without harming normal cells.

Plasmonic Ag decorated CdMoO4 as an efficient photocatalyst for solar hydrogen production

The synthesis of Ag-nanoparticle-decorated CdMoO₄ and its photocatalytic activity towards hydrogen generation under sunlight has been demonstrated. The CdMoO₄ samples were synthesized by a simple hydrothermal approach in which Ag nanoparticles were in situ decorated on the surface of CdMoO₄. A morphological study showed that 5 nm spherical Ag nanoparticles were homogeneously distributed on the surface of CdMoO₄ particles. The UV/DRS spectra show that the band gap of CdMoO₄ was narrowed by the incorporation of a small amount of Ag nanoparticles. The surface plasmonic effect of Ag shows broad absorption in the visible region. The enhanced photocatalytic hydrogen production activities of all the samples were evaluated by using methanol as a sacrificial reagent in water under natural sunlight conditions. The results suggest that the rate of photocatalytic hydrogen production using CdMoO₄ can be significantly improved by loading 2% Ag nanoparticles: i.e. 2465 μmol h⁻¹ g⁻¹ for a 15 mg catalyst. The strong excitation of surface plasmon resonance (SPR) absorption by the Ag nanoparticles was found in the Ag-loaded samples. In this system, the role of Ag nanoparticles on the surface of CdMoO₄ has been discussed. In particular, the SPR effect is responsible for higher hydrogen evolution under natural sunlight because of broad absorption in the visible region. The current study could provide new insights for designing metal/semiconductor interface systems to harvest solar light for solar fuel generation.

Plasmonic enhancement of photocatalytic hydrogen generation is demonstrated using hierarchical Ag decorated CdMoO₄ synthesized using a hydrothermal method.

Realization of High Capacity and Cycling Stability in Pb-Free A2 CuBr4 (A=CH3 NH3 /Cs, 2 D/3 D) Perovskite-Based Li-Ion Battery Anodes

Lead-free hybrid and inorganic perovskites (A₂ CuBr₄ ; A=CH₃ NH₃ or Cs, 2 D or3 D) are synthesized by a room-temperature solid-state reaction route and examined as anode materials in Li-ion batteries. A remarkably high reversible capacity of 630 mAh g^-1 is realized in the 2 D hybrid perovskite at 100 mA g^-1 at the end of 140 cycles. A full cell with this anode is also tested and shows impressive cycling stability. A good reversible capacity of 420 mAh g^-1 with excellent stability tested up to 1400 cycles is also obtained for the 3 D perovskites. Pb-free hybrid/inorganic halide perovskites can thus be used as viable anode materials for battery applications.

Unique CdS@MoS2 Core Shell Heterostructure for Efficient Hydrogen Generation Under Natural Sunlight

The hierarchical nanostructured CdS@MoS2 core shell was architectured using template free facile solvothermal technique. More significantly, the typical hexagonal phase of core CdS and shell MoS2 has been obtained. Optical study clearly shows the two steps absorption in the visible region having band gap of 2.4 eV for CdS and 1.77 eV for MoS2. The FESEM of CdS@MoS2 reveals the formation of CdS microsphere (as a core) assemled with 40-50 nm nanoparticles and covered with ultrathin nanosheets of MoS2 (Shell) having size 200-300 nm and the 10-20 nm in thickness. The overall size of the core shell structure is around 8 µm. Intially, there is a formation of CdS microsphre due to high affinity of Cd ions with sulfur and further growth of MoS2 thin sheets on the surface. Considering band gap ideally in visible region, photocatalytic hydrogen evolution using CdS@MoS2 core shell was investigated under natural sunlight. The utmost hydrogen evolution rate achieved for core shell is 416.4 µmole h-1 with apparent quantum yield 35.04%. The photocatalytic activity suggest that an intimate interface contact, extended visible light absorption and effective photo generated charge carrier separation contributed to the photocatalytic enhancement of the CdS@MoS2 core shell. Additional, the enhanced hole trapping process and effective electrons transfer from CdS to MoS2 in CdS@MoS2 core shell heterostructures can significantly contribute for photocatalytic activity. Such core shell heterostructure will also have potential in thin film solar cell and other microelectronic devices.

Ferrocenylethenyl-substituted oxadiazoles with phenolic and nitro anchors as sensitizers in dye sensitized solar cells

Ferrocenylethenyl-substituted oxadiazoles with phenolic and nitro anchors were synthesized and used as sensitizers in dye sensitized solar cells (DSSCs).

Correction: Unique perforated graphene derived from Bougainvillea flowers for high-power supercapacitors: a green approach

Correction for 'Unique perforated graphene derived from Bougainvillea flowers for high-power supercapacitors: a green approach' by Rajendra P. Panmand et al., Nanoscale, 2017, 9, 4801-4809.

Porous Mn-doped cobalt oxide@C nanocomposite: a stable anode material for Li-ion rechargeable batteries

Cobalt oxide is a transition metal oxide, well studied as an electrode material for energy storage applications, especially in supercapacitors and rechargeable batteries, due to its high charge storage ability. However, it suffers from low conductivity, which effectively hampers its long-term stability. In the present work, a simple strategy to enhance the conductivity of cobalt oxide is adopted to achieve stable electrochemical performance by means of carbon coating and Mn doping, via a simple and controlled, urea-assisted glycine-nitrate combustion process. Structural analysis of carbon coated Mn-doped Co₃O₄ (Mn-Co₃O₄@C) confirms the formation of nanoparticles (∼50 nm) with connected morphology, exhibiting spinel structure. The Mn-Co₃O₄@C electrode displays superior electrochemical performance as a Li-ion battery anode, delivering a specific capacity of 1250 mAh g^-1. Mn-Co₃O₄@C demonstrates excellent performance in terms of long-term stability, keeping charge storage ability intact even at high current rates due to the synergistic effects of fast kinetics-provided by enriched electronic conductivity, which allows ions to move freely to active sites and electrons from reaction sites to substrate during redox reactions-and high surface area combined with mesoporous architecture. The fully assembled battery device using Mn-Co₃O₄@C and standard LiCoO₂ electrode shows 90% capacity retention over 100 cycles.

Synthesis of cerium and nickel doped titanium nanofibers for hydrolysis of sodium borohydride

A recyclable titanium nanofibers, doped with cerium and nickel doped was successfully synthesized by using sol-gel and electrospinning method for hydrogen generation from alkali free hydrolysis of NaBH₄. The resultant nanocomposite was characterized to find out the structural and physical-chemical properties by a series of analytical techniques such as FT-IR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), SEM (scanning electron microscope), EDX (energy-dispersive X-ray spectroscopy),N₂ adsorption-desorption and BET (Brunauer-Emmett-Teller), etc. The results revealed that cerium and nickel nanoparticles were homogeneously distributed on the surface of the TiO₂ nanofibers due to having similar oxidation state and atomic radium of TiO₂nanofibers with CeO₂ and NiO for the effective immobilization of metal ions. The NiO doped catalyst showed superior catalytic performance towards the hydrolysis reaction of NaBH₄ at room temperature. These catalysts have ability to produce 305 mL of H₂ within the time of 160 min at room temperature. Additionally, reusability test revealed that the catalyst is active even after five runs of hydrolytic reaction, implying the as-prepared NiO doped TiO₂ nanofibers could be considered as a potential candidate catalyst for portable hydrogen fuel system such as PEMFC (proton exchange membrane fuel cells).

Hierarchical CdMoO4 nanowire–graphene composite for photocatalytic hydrogen generation under natural sunlight

Herein, a facile in situ solvothermal technique for the synthesis of a CdMoO₄/graphene composite photocatalyst for hydrogen generation under natural solar light.

1,1′-Bis(diphenylphosphino)ferrocene-appended nickel(ii) dithiolates as sensitizers in dye-sensitized solar cells

Herein, two dppf-appended Ni(ii) dithiolates with 2,2-diacetyl and 2-nitro anchors were prepared, and their light harvesting properties were explored in dye-sensitized solar cells (DSSCs).

Perforated N-doped monoclinic ZnWO4 nanorods for efficient photocatalytic hydrogen generation and RhB degradation under natural sunlight

A perforated N-doped monoclinic ZnWO₄ nanorod photocatalyst for excellent hydrogen production via water splitting under sunlight.

Unique perforated graphene derived from Bougainvillea flowers for high-power supercapacitors: a green approach

Herein, we demonstrated a green approach for the synthesis of high surface area (850 m² g^-1) mesoporous perforated graphene (PG) from Bougainvillea flower for the first time using a template free single-step method. The existence of PG was confirmed by XRD, Raman spectroscopy, FESEM, and FETEM. Surprisingly, FETEM clearly showed 5-10 nm perforation on the graphene sheets. More significantly, these mesoporous perforated graphene sheets can be produced in large scale using the present green approach. Considering high surface area and unique perforated graphene architecture, these PGs were studied for supercapacitor applications in detail without any chemical or physical activation. The nanoporosity and high conductivity of PG derived from Bougainvillea flower exhibited excellent supercapacitive performance. According to the supercapacitor study, the synthesized perforated graphene sheets conferred a very high specific capacitance of 458 F g^-1 and an energy density of 63.7 Wh kg^-1 at the power density of around 273.2 Wh kg^-1 in aqueous 1 M Na₂SO₄. Significantly, the areal capacitance of PG was observed to be very high, i.e. 67.2 mF cm^-2. The cyclability study results showed excellent stability of synthesized perforated graphene sheets up to 10 000 cycles. Note that the specific and areal capacitance and the energy density of the synthesized PGs are much higher than the earlier reported values. The high supercapacitive performance may be due to high surface area and mesoporosity of PG. The present approach has a good potential to produce cheaper and high surface area PG. These PGs are good candidates as an anode material in the lithium-ion battery.

Architecture of the CdIn2S4/graphene nano-heterostructure for solar hydrogen production and anode for lithium ion battery

The multi-functionality of the hierarchical CdIn₂S₄/graphene nano-heterostructure prepared using a single step process, as an active photocatalyst for hydrogen production and as an anode for Li-ion batteries has been demonstrated.

Synthesis, characterization and light harvesting properties of Sb(III) and Bi(III) ferrocenyl dithiocarbamate complexes

New Sb(III) and Bi(III) ferrocenyl dithiocarbamate complexes viz. [Sb(FcCH2Bzdtc)3] (Sb) and [Bi(FcCH2Bzdtc)3] (Bi) (Fc=C5H5FeC5H4-; Bz=C6H5CH2-) have been synthesized and characterized by elemental analyses, IR, (1)H and (13)C NMR spectroscopies. The optical, electrochemical and photovoltaic properties of the synthesized complexes were investigated. The light harvesting properties of both of the compounds have been studied using these compounds as photosensitizers in TiO2-based DSSCs. The photovoltaic devices fabricated by Sb and Bi showed a maximum current conversion efficiency of 1.51% and 0.97%, respectively under 1.5 AM illumination (100 mW cm(-2)) and having incident photon to current efficiency (IPCE) of 38% and 31%, respectively. The reason for the higher efficiency of Sb is due its higher dye loading.

Seeded on-surface supramolecular growth for large area conductive donor–acceptor assembly

A seeded, on-surface, supramolecular growth leads to large area conductive donor–acceptor assembly via evaporation-assisted growth from active termini of solution-formed sheaf-like seeds.

Hierarchical CdS nanostructure by Lawesson's reagent and its enhanced photocatalytic hydrogen production

Lawesson's reagent (LR) has been effectively exploited for the synthesis of hierarchical architectures of cadmium sulphide (CdS) nanostructures for the first time.

Solar light driven dye degradation using novel organo–inorganic (6,13-pentacenequinone/TiO2) nanocomposite

The 6,13-pentacenequinone loaded TiO₂ catalyst was successfully synthesized via simple wet-impregnation. The highest apparent rate constant was observed among the prepared catalysts is 5.2 × 10⁻² min⁻¹ using a PQ/TiO₂ catalyst having 0.2 wt% PQ.

A stable Bi2S3 quantum dot–glass nanosystem: size tuneable photocatalytic hydrogen production under solar light

Herein, we have demonstrated the growth of uniformly distributed Bi₂S₃ QDs in a glass matrix as a visible light active catalyst for efficient solar H₂ production.

Titania nanoparticles synthesis in mesoporous molecular sieve MCM-41

Nanocrystalline titanium oxide (TiO(2)) is one of the most useful oxide material, because of its widespread applications in photocatalysis, solar energy conversion, sensors and optoelectronics. The control of particle size and monodispersity of TiO(2) nanoparticles is a challenging task. The use of MCM-41, an inorganic template of uniform pore size (2-10 nm), can overcome this difficulty and produce stable nanoparticles of uniform size and shape. Here, we demonstrate the synthesis of titania nanoparticles inside the pores of silica based MCM-41 forming a TiO(2)/Si-MCM composite. Composites are formed in the alcoholic medium by incipient wetness impregnation method. Titania particles of average 3 nm size are obtained. Effect of silica and titania precursors on the quality of nanoparticles has been investigated. The characterization of titania-MCM-41 composites has been carried out using a variety of techniques like UV-vis absorption spectroscopy, X-ray diffraction, FT-IR spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and photoluminescence spectroscopy. It has been found that the titania particles are co-ordinated with Si-MCM by SiOTi covalent bond.

Sulfite reductase-mediated synthesis of gold nanoparticles capped with phytochelatin

An enzymatic synthesis route to peptide-capped gold nanoparticles has been developed. Gold nanoparticles were synthesized using alpha-NADPH-dependent sulfite reductase and phytochelatin in vitro. The gold ions were reduced in the presence of the enzyme sulfite reductase, leading to the formation of a stable gold hydrosol of dimensions 7-20 nm and were stabilized by the capping peptide. The nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-visible optical absorption. These studies will help in designing a rational enzymatic strategy for the synthesis of nanomaterials of different chemical compositions, shapes and sizes as well as their separation.

Nitrate reductase-mediated synthesis of silver nanoparticles from AgNO3

Synthesis of silver nanoparticles using alpha-NADPH-dependent nitrate reductase and phytochelatin in vitro has been demonstrated for the first time. The silver ions were reduced in the presence of nitrate reductase, leading to the formation of a stable silver hydrosol 10-25 nm diam. and stabilized by the capping peptide. The nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-Vis absorption. These studies will help in designing a rational enzymatic strategy for the synthesis of nanomaterials of different chemical composition, shapes and sizes as well as their separation.