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The present article reports the synthesis, characterization and spin-polarized electronic structure of Cu2MnSnS4 (CMTS) quantum dots. Optimization of the hydrothermal physical parameters including reaction temperature and duration has been performed. The CMTS material synthesized was characterized for its structural, morphological, chemical, compositional optical and electrochemical properties. Variation of the reaction parameters made it possible to get an idea about the process of material formation. Formation mechanism, secondary phase detection and single-phase crystallinity are achieved robustly. Single phase tetragonal CMTS was synthesized just after 8 h reaction duration. Significant reactions parameters like, prolonged reaction duration and higher temperatures influence the morphology and hence resulted in enhanced crystallinity of these nanostructures. Variable structural morphologies and shapes like polygons, cauliflower and quantum dots as small as 4–5 nm were synthesized. Optical properties indicated that the quantum dots are highly active in the visible range of the optical spectrum. Also, the electronic structure calculations for this material tracked the 1.4 eV band gap confirmed from absorption spectrum. Electrochemical properties showed the material is having pseudocapacitive nature exhibiting specific capacitance of 268 F/g revealing its charge storing ability. [ABSTRACT FROM AUTHOR]

In the present article we report a comparative experimental and theoretical study on the structural and optical properties of ZnO. First principle calculations were carried out using density functional theory (DFT) to study the electronic structure of ZnO. The direct‐type band gap was found in the ZnO's typical estimated energy band structure in the Brillouin zone path G‐G or in the middle of the Γ k‐point grid. To develop UV/ZnO/O2/H2O2 system for photodegradation of organic contaminants in an aqueous system, zinc oxide (ZnO) nanostructures were synthesized using an ultrasonication process at ambient temperature. To test the photocatalytic activity of synthesized nanostructures, we used phenol red (PR) dye as a test substrate. We found that ZnO nanostructures photo‐degraded PR dye at a rate of over 90% under ultraviolet light irradiation, converting photonic energy into chemical energy (photocatalytic energy conversion) that can be used for water purification. To explore the structural, optical, morphological, and compositional characteristics of synthesized ZnO nanostructures, various techniques including powder X‐ray diffraction, Fourier‐transform infrared spectroscopy, UV‐visible spectroscopy, scanning electron microscopy, and energy dispersive X‐ray spectroscopy were used. [ABSTRACT FROM AUTHOR]

In this paper, the hydrothermal synthesis of TiO2 nanostructures was analyzed for their structural, morphological, elemental, and optical Properties. X‐ray diffraction (XRD) confirms a highly crystalline nature and reveals that the TiO2 nanocrystals crystallize in the body‐centered tetragonal phase. Scanning electron microscopy (SEM) results show that all the samples are composed of microspheres that are formed from the agglomeration of smaller nanoparticles. The size of the microspheres varies from sample to sample and has a direct relation to the volume of the precursors used. Energy‐dispersive X‐ray analysis (EDAX) shows that the synthesized materials are in good stoichiometry with uniform distribution of the constituents throughout the sample. Fourier transform infrared spectrum of different samples showed a 100% transmittance peak in the 500 to 1000 cm−1 region. Ultraviolet (UV) and visible spectroscopy shows that the material has a good absorption in the visible region and is suitable for photocatalysis. The bandgap of the samples was determined by using the Tauc plot. The synthesized material was used for the photocatalytic degradation of methyl red (MR), a hazardous dye. The 95% degradation of MR occurred in the presence of UV light. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis of MnTiO3 nanoparticles employing a simple, eco‐friendly and low‐cost hydrothermal method. The properties of MnTiO3 nanoparticles were analysed by XRD, FTIR, FE‐SEM, TEM and thermogravimetric analysis (TGA). Structural properties revealed that the MnTiO3 have rhombohedral phase. Morphological studies revealed that the synthesised sample has granular‐like structure. FTIR technique confirmed the formation of MnTiO3 nanoparticles. TGA shows that the as synthesised sample is thermally more stable. The electrochemical detection of acetaminophen (AMP) by using nano‐perovskite‐type manganese titanate (MnTiO3)‐modified glassy carbon electrode is reported. The conductive behaviour of MnTiO3‐modified glassy carbon electrode (MnTiO3/GCE) was confirmed by cyclic voltammetry (CV). Differential pulse voltammetry (DPV) was employed for the detection of AMP. DPV technique showed a comparatively lower detection potential with a higher peak response towards AMP sensing with a linear range of 1.3 to 13.8 μM. The limit of detection and sensitivity were found 1.26 μM and 36.22 μA μM−1 m−2, respectively. Moreover, the modified electrode also demonstrated better repeatability, reproducibility and higher stability, hence used for the analysis of AMP in pharmaceutical and human serum samples with good recoveries. Electrochemical properties showed that the MnTiO3 perovskite has specific capacitance 357.2 F g−1 revealing its charge storing ability. [ABSTRACT FROM AUTHOR]

In this study, novel growth of WO3-ZnSe nanocomposites was carried out by a simple, low-cost hydrothermal process under subcritical conditions and is reported for the first time in just 5 h. The products were characterized in detail by multiform techniques: X-ray diffraction, scanning electron microscopy (SEM), optical studies, and Fourier transform analysis. The influence of ZnSe on the structural, morphological, compositional, optical, and catalytic properties of WO3 is demonstrated. The WO3 metal oxide material is grown in a hexagonal crystal structure with wide-band-gap and has been modified by ZnSe to form a composite nanostructures in the nanoscale range. The electrochemical properties of the prepared materials were studied by cyclic voltammetry, which revealed that the synthesized material exhibited remarkable electrochemical supercapacitive activity. Moreover, the composite nanostructures showed excellent photocatalytic activity for degradation of phenol and almost 93% of phenol was degraded with good recyclability and stability. According to The International Commission on Illumination (CIE), the synthesized nanomaterial shows blue emission and is suitable for blue LEDs. [ABSTRACT FROM AUTHOR]

Summary: The present article investigates the fabrication of MnSnO3, and Fe doped MnSnO3 perovskite. We are reporting for the first time Fe doping perovskite material. The synthesis has been carried out under subcritical conditions. The optical, electrochemical, and luminescence properties were investigated. The structural determination of nanostructures has been carried out through XRD and Fourier transform infrared (FTIR). Furthermore, scanning electron microscope (SEM) technique was applied to figure out the morphology of nanostructured materials. Later on, the investigation of luminescent properties of Fe doped MnSnO3 material has been carried out by photo luminance. In addition, the material shows applicability toward photoluminescence properties. Commission Internationale de l'Éclairage (CIE) co‐ordinate is used to see the illumination of these materials. Insufficient to this, the optical absorption concludes the reduction of band gap values and tunes up to 2.6 eV from 3.1 eV and makes these materials active in the visible region. Finally, the electrochemical activity reflects the pseudo capacitor behavior of synthesized material and the value of capacitance enhances with an increase in the content of iron (Fe) in the host lattice. [ABSTRACT FROM AUTHOR]

Mn doping in SrSnO 3 perovskite material via hydrothermal process under subcritical conditions is reported for the very first time. The present article aims to carry this perovskite suitable for blue light-emitting diodes (LEDs) and spintronic applications. The influence of various Mn doping percentages on structural, morphological, compositional, optical, photoluminescent, and magnetic properties of SrSnO 3 is demonstrated. The perovskite material is grown in an orthorhombic crystal structure having a space symmetry of Pnma along with point group of mmm as determined from the Rietveld refinement. Doping is an excellent way to modify the properties of wide-band-gap perovskite nanostructures. Incorporation of Mn is the result of exact substitution. Morphological studies indicate formation of rodlike structures with thickness in nanoscale dimensions (180-280 nm), and the thickness is a function of doping concentration. The higher doping concentration resulted in enhanced growth of the nanorods. Selected area electron diffraction (SAED) results showed the single-crystal nature of the nanorods. Thermogravimetric analysis (TGA) confirmed the high stability of the material at elevated temperatures. Also, the doped perovskite material is transparent in the visible light, active in the ultraviolet region having a band gap of ∼2.78 eV, and is tuned up to 2.25 eV as the Mn doping concentration reaches 10%. The transfer of excitonic energy from the host material to the dopant Mn 2+ ion leads to the formation of spin-forbidden [ 4 T 1 - 6 A 1 ] emission. Later on, photoluminescence study indicates an enhancement in luminescence behavior of Mn doped perovskite nanostructures. The Commission Internationale de l'éclairage (CIE) diagram drawn to find the color coordinates of the nanorods determines their suitability for blue LEDs. In addition, Mn doping results the conversion of diamagnetic SrSnO 3 into a ferromagnetic material, making the nanorods suitable for spintronic applications., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)