Ag-SPR and semiconductor interface effect on a ternary CuO@Ag@Bi2S3 Z-scheme catalyst for enhanced removal of HIV drugs and (photo)catalytic activity

The development of ternary composites has gained great interest as they can be used as a catalyst due to the different semiconductors with the variation in the band edge positions creates a potential gradient at the composite interface.

Synthesis and catalytic utilization of bimetallic systems for wastewater remediation: A review

The environment is affected by agricultural, domestic, and industrial activities that lead to drastic problems such as global warming and wastewater generation. Wastewater pollution is of public concern, making the treatment of persistent pollutants in water and wastewater highly imperative. Several conventional treatment technologies (physicochemical processes, biological degradation, and oxidative processes) have been applied to water and wastewater remediation, but each has numerous limitations. To address this issue, treatment using bimetallic systems has been extensively studied. This study reviews existing research on various synthesis methods for the preparation of bimetallic catalysts and their catalytic application to the treatment of organic (dyes, phenol and its derivatives, and chlorinated organic compounds) and inorganic pollutants (nitrate and hexavalent chromium) from water and wastewater. The reaction mechanisms, removal efficiencies, operating conditions, and research progress are also presented. The results reveal that Fe-based bimetallic catalysts are one of the most efficient heterogeneous catalysts for the treatment of organic and inorganic contamination. Furthermore, the roles and performances of bimetallic catalysts in the removal of these environmental contaminants are different.

1,3-Disulfoimidazolium chloronickellate immobilized HZSM-5 framework as visible-light-induced heterogeneous photocatalyst for advanced oxidation process

Hybrid photocatalysts of [Dsim]₂[NiCl₄]/HZSM-5 were prepared by wet impregnation and their application is demonstrated as feasible heterogeneous photocatalysts for oxidative degradation of methylene blue under sunlight.

Morphological Control of Mesoporosity and Nanoparticles within Co3O4-CuO Electrospun Nanofibers: Quantum Confinement and Visible Light Photocatalysis Performance

The one-dimensional (1D) mesoporous and interconnected nanoparticles (NPs) enriched composite Co₃O₄-CuO nanofibers (NFs) in the ratio Co:Cu = 1/4 (Co₃O₄-CuO NFs) composite have been synthesized by electrospinning and calcination of mixed polymeric template. Not merely the mesoporous composite Co₃O₄-CuO NFs but also single mesoporous Co₃O₄ NFs and CuO NFs have been produced for comparison. The choice of mixed polymer templates such as polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) for electrospinning is responsible for the formation of 1D mesoporous NFs. The HR-TEM result showed evolution of interconnected nanoparticles (NPs) and creation of mesoporosity in all electrospun NFs. The quantum confinement is due to NPs within NFs and has been proved by the surface-enhanced Raman scattering (SERS) study and the UV-vis-NRI diffuse reflectance spectra (DRS). The high intense photoluminescence (PL) spectra showing blue shift of all NFs also confirmed the quantum confinement phenomena. The lowering of PL spectrum after mixing of CuO in Co₃O₄ nanofibers framework (Co₃O₄-CuO NFs) proved CuO as an efficient visible light response low cost cocatalyst/charge separator. The red shifting of the band gap in composite Co₃O₄-CuO NFs is due to the internal charge transfer between Co²⁺ to Co³⁺ and Cu²⁺, proved by UV-vis absorption spectroscopy. Creation of oxygen vacancies by mixing of CuO and Co₃O₄ also prevents the electron-hole recombination and enhances the photocatalytic activity in composite Co₃O₄-CuO NFs. The photocurrent density, Mott-Schottky (MS), and electrochemical impedance spectroscopy (EIS) studies of all NFs favor the high photocatalytic performance. The mesoporous composite Co₃O₄-CuO NFs exhibits high photocatalytic activity toward phenolic compounds degradation as compared to the other two NFs (Co₃O₄ NFs and CuO NFs). The kinetic study of phenolic compounds followed first order rate equation. The high photocatalytic activity of composite Co₃O₄-CuO NFs is attributed to the formation of mesoporosity and interconnected NPs within NFs framework, quantum confinement, extended light absorption property, internal charge transfer, and effective photogenerated charge separations.