For enhancement of visible-light-driven degradation of tetracycline (TCL), this work reports synthesis of a Fe-assisted Fe-AC/AgI nanocomposite which is prepared using a simple co-precipitation approach. Herein, XRD and FESEM analyses confirmed the formation of a well-crystallized material which comprises a stable structural framework along with uniform morphology composed of well-interconnected particles. Whereas, optical and electrochemical characterizations further demonstrate that AgI possesses a suitable, aligned band structure for visible-light activation, and revealing an optical band gap of 2.53 eV. The Fe2+ ions introduced effective electron-trapping sites, which helped in the suppression of rapid e−/h+ recombination and promoted the generation of reactive oxygen species, particularly ⋅OH and ⋅O₂− radicals. These radicals play a decisive role in degradation of TCL. Due to which, the Fe-AC/AgI photocatalyst achieved a notable degradation efficiency of about 89.77
Layered double hydroxides (LDHs) offer tunable structures and abundant active sites but suffer from poor conductivity. Here, we construct NiCo LDH/TiO2 composite catalysts on nickel foam via a hydrothermal method and systematically vary the Ni/Co ratio to optimize the bimetallic composition for enhanced hydrogen evolution reaction (HER) performance. Structural characterization confirms the presence of TiO2 and the characteristic chemical states of NiCo LDH. Among the compositions investigated, a Ni/Co ratio of 2:1 produces uniformly distributed nanosheets with an open porous architecture and close contact between NiCo LDH and TiO2. The corresponding catalyst exhibits the lowest charge-transfer resistance and the highest double-layer capacitance of 3.87 mF·cm−2 among the tested samples, consistent with facilitated charge transfer and increased active-site exposure. The optimized catalyst achieves an overpotential of 86.8 mV at 10 mA·cm−2 in 1 M KOH, with a Tafel slope of 61 mV·dec−1. Its operational stability was assessed by chronoamperometry at a constant potential for 10 h. These results link Ni/Co composition optimization to favorable morphology and electrochemical properties, providing a basis for the compositional design of LDH-based composite catalysts for alkaline HER.
The performance of bifunctional Ni–Re/zeolite catalysts in fatty-acid deoxygenation depends on the spatial organization of the metallic and acidic functions. In this work, the preparation sequence of bifunctional Ni–Re/HZSM-5 catalysts was varied to determine how metal organization and accessible acidity affect oleic acid hydrotreatment. Catalysts nominally containing 6 wt
The durability of solid acid catalysts is often limited by the loss of accessible acid sites during catalytic operation. In this work, tungsten-modified sulfated titania (WST) was developed for the transesterification of ethyl acetate with n-butanol, and its post-reaction accessible Brønsted acid-site retention behavior was evaluated using the Dynamic Brønsted Acid Retention (DBAR) descriptor based on ex situ pyridine-FTIR analysis. Structural characterization confirmed the preservation of the anatase TiO2 framework and the high dispersion of tungsten species without detectable crystalline WO3 phases. Pyridine adsorption indicated the retention of accessible Brønsted acid sites after reaction. The WST catalyst maintained a higher DBAR value (48.1
The Co3O4-based catalyst was prepared via precipitation method, followed by lanthanum incorporation through incipient wetness impregnation. All catalysts were evaluated in the preferential oxidation (PROX) of carbon monoxide in hydrogen-rich streams. Catalysts were characterised using XRD, BET surface area, TGA, SEM, TEM, FTIR, TPR, and XPS. The XRD and FTIR results confirmed the formation of the spinel CO3O4 phase. The TPR measurements suggest the formation of LaCo linkage, which evidences strong electronic and structural interaction between La species and the Co3O4 lattice. An increase in the Co3+/Co2+ ratio was observed over the catalyst loaded with 1 wt
