Acta Phys. -Chim. Sin. ›› 2026, Vol. 42 ›› Issue (10): 100338.doi: 10.1016/j.actphy.2026.100338

• ARTICLE • Previous Articles     Next Articles

Tuning antibonding-orbital occupancy in pyrene-COFs via electron-donating phenolic −OH for boosted photocatalytic H2 evolution

Yongkang Liu1, Shouxi Yu2, Li Chen2, Zhongliao Wang2,*(), Meiyu Zhang3,*(), Jinfeng Zhang1,*()   

  1. 1 Anhui Province Key Laboratory of Intelligent Computing and Applications, College of Physics and Electronic Engineering, Huaibei Normal University, Huaibei 235000, Anhui Province, China
    2 College of Energy Science and Engineering, Huaibei Normal University, Huaibei 235000, Anhui Province, China
    3 Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry & Chemical Engineering, Liaocheng University, Liaocheng 252059, Shandong Province, China
  • Received:2026-05-04 Revised:2026-05-30 Accepted:2026-06-01 Published:2026-09-03
  • Contact: Email: wangzl@chnu.edu.cn (Zhongliao Wang)zhangmeiyu@lcu.edu.cn (Meiyu Zhang)jfzhang@chnu.edu.cn (Jinfeng Zhang)

Abstract:

Covalent organic frameworks (COFs) are widely studied as photocatalysts for the hydrogen evolution reaction (HER), yet most design strategies target light absorption or charge separation rather than the H* desorption barrier at the catalytic site itself. We re-examine the problem from a bond-resolved view: the crystal orbital Hamilton population (COHP) is used to treat the occupancy of the N−H antibonding manifold as a quantitative descriptor of how strongly the imine nitrogen of a Schiff-base COF binds H*. Two pyrene-based COFs, PY-BD and PY-DHBD, are synthesized to test the descriptor. Adding two phenolic −OH groups to the dialdehyde linker raises the antibonding occupancy (ICOHP from −7.52 to −7.18 eV), weakens the N−H bond, and shifts ΔGH* from −0.22 to 0.04 eV, close to thermoneutrality. The visible-light H2-evolution rate accordingly rises from 450 to 1127 μmol g−1 h−1, 2.5-fold the rate of PY-BD. The work places COHP-resolved antibonding occupancy alongside the d-band-centre framework familiar from metal catalysis as a quantitative descriptor for tuning HER on N-rich COF active sites.

Key words: Pyrene-COFs, Electron-donating, Phenolic ?OH, Photocatalytic HER, COHP