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Understanding the electronic structure of photocatalysts is crucial for enhancing their efficiency. In this study, we have successfully synthesized novel monoclinic bismuth vanadate (Bi7VO13) nanoparticles using the gas phase condensation technique, with an average particle size of 40 nm. To investigate the crystallographic structure of the as-synthesized nanoparticles, we conducted X-ray diffraction (XRD) experiments. Additionally, we employed advanced characterization techniques to provide a detailed analysis of the electronic structure of Bi7VO13 nanoparticles. This study presents the first report on the electronic structure of Bi7VO13 nanoparticles using the aforementioned spectroscopic methods. Remarkably, the investigation revealed that the valence band maximum (VB) and conduction band minimum (CB) are dominated by O 2p and V 3d states, respectively. Moreover, X-ray absorption spectroscopy (XAS) reveals splitting the V 3d conduction band state into a triplet d-manifold at the V L-edge and O K-edge. This splitting arises from the lattice distortion induced by lone pairs, which gives rise to a band gap of 2.28 eV. Under visible light irradiation, the Bi7VO13 nanoparticles exhibit efficient visible light absorption, highlighting their potential for photocatalytic applications. Notably, our experiments demonstrated outstanding photodegradation properties of methylene blue, serving as a model effluent, further underscoring the photocatalytic progress of Bi7VO13 nanoparticles. In conclusion, this research explains the functioning of Bi7VO13 photocatalysts and opens the doors for utilizing their potential to generate a cleaner and brighter future. [ABSTRACT FROM AUTHOR]

Here, we report tailor made phase of iron nanoparticles using homogeneous gas phase condensation process via thermal plasma route. It was observed that crystal lattice of nanocrystalline iron changes as a function of operating parameters of the plasma reactor. In the present investigation iron nanoparticles have been synthesized in presence of argon at operating pressures of 125-1000 Torr and fixed plasma input DC power of 6 kW. It was possible to obtain pure fcc, pure bcc as well as the mixed phases for iron nanoparticles in powder form as a function of operating pressure. The as synthesized product was characterized for understanding the structural and magnetic properties by using X-ray diffraction, vibrating sample magnetometer, and Mössbauer spectroscopy. The data reveal that fcc phase is ferromagnetically ordered with high spin state, which is unusual whereas bcc phase is found to be ferromagnetic as usual. Finally, the structural and magnetic properties are co-related. [ABSTRACT FROM AUTHOR]

The paper addresses the issue of phase formation in the nano-crystalline binary alloys of Fe Ni and Al Ni, synthesized by plasma assisted vapor phase condensation process. In depth experimental analysis of the crystal structure, for the alloy nanoparticles with different compositions, is presented. The observed crystalline phases of the products have been compared with those expected from the standard phase diagram of the respective alloys. Crystalline phases of Fe Ni system showed no deviation, whereas, those of Al Ni showed considerable deviation. Differences in the thermo-physical properties of Al and Ni are shown to be responsible for such a deviation. The results are supported by a computational model, which accounts for the supersaturation of the species in gas phase, leading to nucleation and growth. [ABSTRACT FROM AUTHOR]