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Two-Dimensional Covalent Heptazine-Based Framework Enables Highly Photocatalytic Performance for Overall Water
Yingnan Zhao1, Cong Wang2, Xingqi Han1
1Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun, 130024, P. R. China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|August 10, 2022
Summary
Researchers developed novel heptazine-based frameworks for efficient solar-to-hydrogen energy conversion. These materials enable visible-light-driven overall water splitting (OWS) without sacrificial agents, with one catalyst achieving 12.04% efficiency.
Area of Science:
- Materials Science
- Photocatalysis
- Renewable Energy
Background:
- Visible-light-driven overall water splitting (OWS) is crucial for solar-to-hydrogen (STH) energy conversion.
- Heptazine units are promising building blocks for hydrogen evolution reactions (HER).
Purpose of the Study:
- To screen high-efficiency 2D conjugated polymers for visible-light-driven OWS.
- To develop novel heptazine-based frameworks (CHFs) for photocatalytic water splitting.
Main Methods:
- Covalent linking of heptazine units with alkynyl and phenyl moieties to construct 10 CHFs.
- Computational screening of CHFs for OWS photocatalytic activity.
- Analysis of spatial separation of HER and oxygen evolution reaction (OER) active sites.
Main Results:
- Four CHFs (CHF-4, CHF-7, CHF-8, CHF-9) showed promising OWS performance.
- Spatially separated HER (heptazine) and OER (alkynyl/phenyl) active sites were observed.
- CHF-7 exhibited the highest STH energy conversion efficiency at 12.04% without sacrificial agents or cocatalysts.
Conclusions:
- The developed CHFs are efficient photocatalysts for spontaneous OWS under visible light.
- CHF-7 demonstrates significant potential for industrial OWS applications.
- This work offers a new strategy for designing heptazine-based photocatalysts for STH energy conversion.
Keywords:
2D covalent heptazine-based frameworksdensity functional theory calculationsoverall water splittingphotocatalysisMore Related Videos
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