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Updated: May 8, 2026
Synthesis and Performance Evaluations of ZnCoS/ZnCdS with Twin Crystal Structure for Multifunctional Redox Photocatalysis in Energy Applications
Published on: July 25, 2025
Elucidating a twin-dependent chemical activity of hierarchical copper sulfide nanocages
Shaodong Sun1, Dongchu Deng, Xiaoping Song
1Laboratory for Mechanical Behavior of Materials, MOE Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed Matter, Xi'an Jiaotong University, Xi'an 710049, ShaanXi, People's Republic of China. zmyang@mail.xjtu.edu.cn.
Abstract:
We have demonstrated significant evidence of a solvent-dependent synthesis of hierarchical Cu7S4 polycrystalline nanocage assemblies with controllable aggregation-based building blocks by a sacrificial Cu2O template approach. The formation of a hierarchical Cu7S4 polycrystalline nanocage is essentially determined by a Kirkendall effect, which is attributed to the tailored-aggregation behaviour of the nanoscale building blocks during the replacement/etching process in different polarities of solvent. The hierarchical Cu7S4 polycrystalline nanocage assembly of nanoparticle building blocks was prepared in pure water, while the hierarchical Cu7S4 polycrystalline nanocage assembly of twinned nanoplate building blocks was successfully synthesized in an anhydrous ethanol capping environment. Such a hierarchical Cu7S4 polycrystalline nanocage assembly of twinned nanoplate building blocks exhibits a higher photocatalytic activity than that of the common polycrystalline ones. A nanotwin-dependent photochemical mechanism has been proposed. Significantly, this study is of great importance in bottom-up assembly of controllable ordered architectures, and offers a good opportunity to understand the fundamental importance of the formation mechanism and growth process of hierarchical Cu7S4 polycrystalline nanocages with controllable aggregation-based building blocks.
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