Acta Phys. -Chim. Sin. ›› 2024, Vol. 40 ›› Issue (11): 2406027.doi: 10.3866/PKU.WHXB202406027

Special Issue: Solar fuel preparation

• ARTICLE • Previous Articles     Next Articles

Efficient Photocatalytic Production of H2O2 over ZnO/D-A Conjugated Polymer S-scheme Heterojunction and Charge Transfer Dynamics Investigation

You Wu1,2, Chang Cheng2, Kezhen Qi1,*(), Bei Cheng2,*(), Jianjun Zhang3,*(), Jiaguo Yu3, Liuyang Zhang3   

  1. 1 College of Pharmacy, Dali University, Dali 671000, Yunnan Province, China
    2 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
    3 Laboratory of Solar Fuel, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430078, China
  • Received:2024-06-21 Revised:2024-07-25 Accepted:2024-07-26 Published:2024-10-14
  • Contact: Email: qkzh2003@aliyun.com (Kezhen Qi)chengbei2013@whut.edu.cn (Bei Cheng)zhangjianjun@cug.edu.cn (Jianjun Zhang)
  • Supported by:
    Yunnan Provincial Science and Technology Plan Project(202305AF150116); the National Natural Science Foundation of China(22238009); the National Natural Science Foundation of China(U23A20102); the National Natural Science Foundation of China(52073223); the National Natural Science Foundation of China(22278324); the National Natural Science Foundation of China(22361142704); the Natural Science Foundation of Hubei Province of China(2022CFA001); the Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)(CUG22061)

RichHTML

8

Full text @ ScienceDirect

Like

Supplement

1

Abstract:

Photocatalytic technology harnesses clean, non-polluting solar energy to synthesize hydrogen peroxide (H2O2). In this study, ZnO/PBD S-scheme heterojunction composites, featuring ZnO nanoparticles on a donor-acceptor conjugated polymer substrate (PBD), were synthesized via the Suzuki-Miyaura reaction and hydrothermal method. The optimal ZnO/PBD composite achieved an H2O2 production efficiency of 4.07 mmol·g-1·h-1, which is 5.4 times higher than that of pristine ZnO. This significant enhancement is attributed to the formation of S-scheme heterojunctions. The successful construction of S-scheme heterojunctions was confirmed through UV-visible absorption spectroscopy and in situ irradiated X-ray photoelectron spectroscopy. Steady-state photoluminescence and femtosecond transient absorption (fs-TA) spectroscopies identified and verified the presence of defect states in ZnO. These defect states trap photogenerated electrons, adversely affecting the photocatalytic reaction. However, the S-scheme heterojunction effectively promotes the separation and transfer of electrons, mitigating this issue. The measured lifetimes of photogenerated electrons in these defect states, as determined by fitted fs-TA decay kinetics, provided further evidence of the carrier transfer mechanism in S-scheme heterojunctions. This work introduces a novel approach for studying organic/inorganic S-scheme heterojunctions using fs-TA spectroscopy.

Key words: Photocatalytic production of H2O2, S-scheme heterojunction, ZnO defect states, fs-TA spectroscopy