Zi-Zhan Liang, Xin-Ao Li, Qi-Ze Chen, Xiao-Lin Wang, Pei-Yang Su, Jian-Feng Huang, YeCheng Zhou*, Li-Min Xiao and Jun-Min Liu*,
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引用次数: 0
Abstract
Overall water splitting into H2 and H2O2 via Z-scheme piezo-photocatalytic systems is an ideal method for renewable energy production. Herein, we have synthesized a triangular prism-shaped metal–organic cage (MOC-Q3) integrating three catalytic Pd2+ centers and two photosensitive ligands, which is successfully immobilized on a highly crystalline β-ketoenamine-linked covalent organic framework (EA-COF) to form a Z-scheme single-atom photosystem. The optimized MOC-Q3/EA-COF achieves a high H2 yield (26.17 mmol g–1 h–1) with a TONPd of 118,521 with ascorbic acid as sacrificial agent due to broad light absorption, effective carrier separation, and widely distributed Pd active sites, which is among the highest for COF-based solar H2 evolution photocatalysts. Interestingly, EA-COF is found to be a piezoelectric material and its piezoelectric performance is mainly due to the in-plane polarization of the 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde groups in the COF, which is confirmed by experimental observations and density functional theory calculations. The EA-COF shows H2 and H2O2 production rates of 239.94 and 400.38 μmol g–1 h–1, respectively, in pure water when excited by ultrasound coupled with light irradiation. The integration of MOC-Q3 can further enhance the efficiency of EA-COF in piezo-photocatalytic water splitting. The superior MOC-Q3/EA-COF exhibits H2 and H2O2 generation rates of 426.38 and 535.14 μmol g–1 h–1, respectively, outperforming pure EA-COF by 1.8 and 1.3 times. This is a pioneering work to construct a Z-scheme MOC/COF piezo-photocatalytic system, which provides an efficient way to use mechanical and solar energy to produce H2 and H2O2 through overall water splitting.
期刊介绍:
ACS Catalysis is an esteemed journal that publishes original research in the fields of heterogeneous catalysis, molecular catalysis, and biocatalysis. It offers broad coverage across diverse areas such as life sciences, organometallics and synthesis, photochemistry and electrochemistry, drug discovery and synthesis, materials science, environmental protection, polymer discovery and synthesis, and energy and fuels.
The scope of the journal is to showcase innovative work in various aspects of catalysis. This includes new reactions and novel synthetic approaches utilizing known catalysts, the discovery or modification of new catalysts, elucidation of catalytic mechanisms through cutting-edge investigations, practical enhancements of existing processes, as well as conceptual advances in the field. Contributions to ACS Catalysis can encompass both experimental and theoretical research focused on catalytic molecules, macromolecules, and materials that exhibit catalytic turnover.