Molecular and Heterojunction Device Engineering of Solution-Processed Conjugated Reticular Oligomers: Enhanced Photoelectrochemical Hydrogen Evolution through High-Effective Exciton Separation

被引：5

作者：

Zhang, Boying ^{[1
,2
]}

Gao, Huimin ^{[1
]}

Kang, Yazhou ^{[1
]}

Li, Xiaoming ^{[1
]}

Li, Qing ^{[1
]}

Zhai, Pengda ^{[1
]}

Hildebrandt, Diane ^{[3
]}

Liu, Xinying ^{[4
]}

Wang, Yue ^{[1
]}

Qiao, Shanlin ^{[1
]}

机构：

[1] Hebei Univ Sci & Technol, Coll Chem & Pharmaceut Engn, Shijiazhuang 050018, Peoples R China

[2] Univ Johannesburg, Fac Engn & Built Environm, Dept Chem Engn, ZA-2028 Doornfontein, South Africa

[3] Rutgers State Univ, Dept Chem & Biochem Engn, Piscataway, NJ 08854 USA

[4] Univ South Africa, Inst Catalysis & Energy Solut, Florida Campus, ZA-1709 Pretoria, South Africa

来源：

ADVANCED SCIENCE | 2024年 / 11卷 / 18期

基金：

中国国家自然科学基金;

关键词：

bulk heterojunction devices; conjugated reticular oligomers; covalent organic frameworks; photoelectrochemical hydrogen evolution; solution processability photoelectrode; COVALENT ORGANIC FRAMEWORKS; PHOTOANODE; ISOMERISM;

D O I：

10.1002/advs.202308535

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Covalent organic frameworks (COFs) face limited processability challenges as photoelectrodes in photoelectrochemical water reduction. Herein, sub-10 nm benzothiazole-based colloidal conjugated reticular oligomers (CROs) are synthesized using an aqueous nanoreactor approach, and the end-capping molecular strategy to engineer electron-deficient units onto the periphery of a CRO nanocrystalline lattices (named CROs-Cg). This results in stable and processable "electronic inks" for flexible photoelectrodes. CRO-BtzTp-Cg and CRO-TtzTp-Cg expand the absorption spectrum into the infrared region and improve fluorescence lifetimes. Heterojunction device engineering is used to develop interlayer heterojunction and bulk heterojunction (BHJ) photoelectrodes with a hole transport layer, electron transport layer, and the main active layers, using a CROs/CROs-Cg or one-dimensional (1D) electron-donating polymer HP18 mixed solution via spinning coating. The ITO/CuI/CRO-TtzTp-Cg-HP18/SnO2/Pt photoelectrode shows a photocurrent of 94.9 mu A cm-2 at 0.4 V versus reversible hydrogen electrode (RHE), which is 47.5 times higher than that of ITO/Bulk-TtzTp. Density functional theory calculations show reduced energy barriers for generating adsorbed H* intermediates and increased electron affinity in CROs-Cg. Mott-Schottky and charge density difference analyses indicate enhanced charge carrier densities and accelerated charge transfer kinetics in BHJ devices. This study lays the groundwork for large-scale production of COF nanomembranes and heterojunction structures, offering the potential for cost-effective, printable energy systems. Sub-10 nm colloidal conjugated reticular oligomers (CROs) are synthesized using an aqueous nanoreactor. An end-capping molecular strategy is employed to introduce electron-deficient units onto the periphery of a two-dimensional CROs nanocrystalline lattice, denoted as CROs-Cg. This process yields stable, solution-processable '' electronic inks,'' facilitating the fabrication of flexible photoelectrodes for photoelectrochemical water reduction through device engineering, resulting in outstanding photocurrent performance. image

引用

页数：14