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Summary: We studied Na0.8Ni0.33Co0.33Mn0.33O2 nanoparticles synthesized using water‐based extract procured from the dried silk of maize (Zea mays lea) plant. The synthesized Na0.8Ni0.33Co0.33Mn0.33O2 was used as the positive electrode in an aqueous sodium ion battery (SIB). X‐ray diffraction (XRD) studies of the biosynthesized material reveal that it can be indexed to the trigonal structure of Na0.8Ni 0.33Co0.33Mn0.33O2 with an R 3m space group (160), (ICSD 184736) although impurities of Mn2O3 and NiO were detected. Surface morphological studies from a scanning electron microscope (SEM) disclose that the nanoparticles consist of an interspersion of sheath‐like particles with quasi‐spherical nanoparticles of uneven dimensions. The sheath‐like particles seem to agglomerate to form layers that coalesce into flower‐like structures that are spread within the quasi‐spherical nanoparticles. The material yielded a rechargeable discharge capacity of about 86 mA h g−1 in a three‐electrode system consisting of platinum, the Na0.8Ni0.33Co0.33Mn0.33O2 and Ag/AgCl as the counter, working and reference electrodes respectively at a current density of 10 mA g−1. However, a full cell using P25 Degussa TiO2 and the biosynthesized Na0.8Ni0.33Co0.33Mn0.33O2 as the negative and the positive electrode, respectively, and having a mass ratio of 1:1 yielded a discharge capacity of 49 mA h g−1 at a current density of 5 mA g−1. Impedance studies for a symmetrical cell developed showed that the magnitude of the impedance is highest at 0% and 100 state of charge (SOC). [ABSTRACT FROM AUTHOR]

Summary: Researchers have at different times focused on designing perovskite solar cells (PSCs) that are flexible yet highly efficient, to enable the fabrication of portable photovoltaic solar cell (PVSC) devices in large quantities. This upcoming organometal trihalide perovskite has high tendencies of being a highly efficient, yet inexpensive solar cell. This is because the solution processing method is carried out at a reduced temperature and increased solar to electricity conversion efficiency (>25%) obtained within few innovative years. The nanostructured morphology and film quality is essential in obtaining functional power conversion efficiency. It could be a great task for the two characteristics to be present, especially within solutions where very good films are in contact with smooth morphological surfaces. A fast increase in the energy conversion efficiency of these PSCs incorporated with metal halides has been recorded. The next line of research should be to extend the existing models to 3D explicit models of the meso‐structured layer, to verify the 1D effective medium method discussed in the literature. Several models have been discussed to that effect. This review intensively discusses several perovskite models in a bid to understand PSCs. The challenges and future perspectives have also been highlighted. [ABSTRACT FROM AUTHOR]

Summary: The effect of 8.0 MeV carbon ions (C++) radiations on features and performances of MnO2–NiO–ZnO@GO electrodes (thin films). MnO2–NiO–ZnO@GO thin films were produced using the hydrothermal technique. 8.0 MeV carbon ions (C++) with doses of 2.25 × 1015, 5.0 × 1015, 7.5 × 1015 and 1.0 × 1016 ions/cm2 were irradiated on MnO2–NiO–ZnO@GO thin films. The XRD spectra indicate crystalline nature of the films while SEM images show rod‐like structures. The XRD calculated crystallite sizes varied from 1.24 to 5.58 nm. Energy‐dispersive X‐ray spectroscopy, Proton induced X‐ray emission (PIXE) and Rutherford back scattering (RBS) analysis are used to evaluate the elemental compositions of samples. Optical studies show reduced bandgap energies of various oxides due to the addition of graphene oxide. The electrochemical studies obtained a specific capacitance of 1627 and 1960 F/g for electrodes illuminated with radiation doses of 5.0 × 1015 and 7.5 × 1015 ions/cm2, respectively. Results indicate that carbon ion irradiation with low doses improved the performances of the nanostructured thin films while radiation with high doses induces adverse disorder and flaw to the MnO2–NiO–ZnO@GO thin film properties. These results show that ion beam irradiation is a useful tool to enhance or damage the properties of nanostructured materials depending on the dosages radiation beamed on the material. [ABSTRACT FROM AUTHOR]

Most recently, green synthesis of metal oxide nanoparticles has become an interesting subject of the nanoscience and nanotechnology. The use of plant systems has been deemed a green route and a dependable method for nanoparticle biosynthesis, owing to its environmental friendly nature. The present work demonstrates the bioreductive green synthesis of nanosized zinc oxide (ZnO) using peel extracts of pomegranate. Highly crystalline ZnO nanoparticles (ZnO NPs) which are 5 nm in particle size were characterised by HRTEM and XRD. FT-IR spectra confirmed the presence of the biomolecules and formation of plant protein-coated ZnO NPs and also the pure ZnO NPs. Electrochemical investigation revealed the redox properties and the conductivity of the as-prepared ZnO nanoparticles. The optical band gap of ZnO NPs was calculated to be 3.48 eV which indicates that ZnO NPs can be used in metal oxide semiconductor-based devices. Further, the nanomaterials were also found to be good inhibitors of bacterial strains at both low and high concentrations of 5–10 mg mL−1. [ABSTRACT FROM AUTHOR]

Nanocomposites based on few-layers graphene oxide (FGO) decorated with porphyrin nanorods (PN) were synthesized and the interfacial interaction between these two components was investigated by using scanning electron microscopy (SEM), photoluminescence spectroscopy, resonant Raman scattering and Fourier transform infrared (FT-IR) techniques. SEM showed good exfoliation of FGO and its successful interaction with the PN. The photoluminescence results showed an important interaction between FGO and PN resulting in a quenching of the photoluminescence of the PN-FGO composite. Resonant Raman with PN aggregates and FT-IR results revealed a π- π intermolecular interaction confirming the energy/charge transfer. Moreover, the investigation of X-ray diffraction confirmed the intercalation of PN in FGO and their disaggregation. The findings presented here are an important contribution to achieving the functionalization of graphene derivative surfaces with PN for various optoelectronic applications and particularly photovoltaic cells. [ABSTRACT FROM AUTHOR]