Shuai Liu, Yang Meng, Zhengfei Chen, Jiefeng Yan, Fuyan Gao, Tao Wu, Guangsuo Yu
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引用次数: 0
Abstract
Engineering phase-selective gel composites presents a promising route to enhance both CO2 adsorption and conversion efficiency in photocatalytic systems. In this work, Cu9S5/TiO2 gel composites were synthesized via a hydrazine-hydrate-assisted hydrothermal method, using TiO2 derived from a microwave-assisted sol-gel process. The resulting materials exhibit a porous gel-derived morphology with highly dispersed Cu9S5 nanocrystals, as confirmed by XRD, TEM, and XPS analyses. These structural features promote abundant surface-active sites and interfacial contact, enabling efficient CO2 adsorption. Among all samples, the optimized 0.36Cu9S5/TiO2 composite achieved a methane production rate of 34 μmol·g-1·h-1, with 64.76% CH4 selectivity and 88.02% electron-based selectivity, significantly outperforming Cu9S8/TiO2 synthesized without hydrazine hydrate. This enhancement is attributed to the dual role of hydrazine: facilitating phase transformation from Cu9S8 to Cu9S5 and modulating the interfacial electronic environment to favor CO2 capture and activation. DFT calculations reveal that Cu9S5/TiO2 effectively lowers the energy barriers of critical intermediates (*COOH, *CO, and *CHO), enhancing both CO2 adsorption strength and subsequent conversion to methane. This work demonstrates a gel-derived composite strategy that couples efficient CO2 adsorption with selective photocatalytic reduction, offering new design principles for adsorption-conversion hybrid materials.
期刊介绍:
The journal Gels (ISSN 2310-2861) is an international, open access journal on physical (supramolecular) and chemical gel-based materials. Our aim is to encourage scientists to publish their experimental and theoretical results in as much detail as possible. Therefore, there is no restriction on the maximum length of the papers, and full experimental details must be provided so that the results can be reproduced. Short communications, full research papers and review papers are accepted formats for the preparation of the manuscripts.
Gels aims to serve as a reference journal with a focus on gel materials for researchers working in both academia and industry. Therefore, papers demonstrating practical applications of these materials are particularly welcome. Occasionally, invited contributions (i.e., original research and review articles) on emerging issues and high-tech applications of gels are published as special issues.