Wang Lei, Lian Weitao, Liu Bin, Lv Haifeng, Zhang Ying, Wu Xiaojun, Wang Tuo, Gong Jinlong, Chen Tao, Xu Hangxun
Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China.
Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China.
Adv Mater. 2022 Jul;34(29):e2200723. doi: 10.1002/adma.202200723. Epub 2022 Jun 12.
Developing low-cost, high-performance, and durable photoanodes is essential in solar-driven photoelectrochemical (PEC) energy conversion. Sb S is a low-bandgap (≈1.7 eV) n-type semiconductor with a maximum theoretical solar conversion efficiency of ≈28% for PEC water splitting. However, bulk Sb S exhibits opaque characteristics and suffers from severe photocorrosion, and thus the use of Sb S as a photoanode material remains underexploited. This study describes the design and fabrication of a transparent Sb S -based photoanode by conformably depositing a thin layer of conjugated polycarbazole frameworks (CPF-TCzB) onto the Sb S film. This structural design creates a type-II heterojunction between the CPF-TCzB and the Sb S with a suitable band-edge energy offset, thereby, greatly enhancing the charge separation efficiency. The CPF-TCzB/Sb S hybrid photoanode exhibits a remarkable photocurrent density of 10.1 mA cm at 1.23 V vs reversible hydrogen electrode. Moreover, the thin CPF-TCzB overlayer effectively inhibits photocorrosion of the Sb S and enables long-term operation for at least 100 h with ≈10% loss in photocurrent density. Furthermore, a standalone unbiased PEC tandem device comprising a CPF-TCzB/Sb S photoanode and a back-illuminated Si photocathode can achieve a record solar-to-hydrogen conversion efficiency of 5.21%, representing the most efficient PEC water splitting device of its kind.
开发低成本、高性能且耐用的光阳极对于太阳能驱动的光电化学（PEC）能量转换至关重要。Sb₂S₃是一种低带隙（≈1.7 eV）的n型半导体，用于PEC水分解的最大理论太阳能转换效率约为28%。然而，块状Sb₂S₃具有不透明的特性，并且遭受严重的光腐蚀，因此将Sb₂S₃用作光阳极材料的应用仍未得到充分开发。本研究描述了通过在Sb₂S₃薄膜上均匀沉积一层共轭聚咔唑骨架（CPF-TCzB）来设计和制造透明的Sb₂S₃基光阳极。这种结构设计在CPF-TCzB和Sb₂S₃之间形成了具有合适带边能量偏移的II型异质结，从而大大提高了电荷分离效率。CPF-TCzB/Sb₂S₃混合光阳极在相对于可逆氢电极1.23 V时表现出10.1 mA cm⁻²的显著光电流密度。此外，薄的CPF-TCzB覆盖层有效地抑制了Sb₂S₃的光腐蚀，并能够实现至少100小时的长期运行，光电流密度损失约10%。此外，一个由CPF-TCzB/Sb₂S₃光阳极和背照式硅光电阴极组成的独立无偏压PEC串联器件可以实现创纪录的5.21%的太阳能到氢能转换效率，代表了同类中最有效的PEC水分解装置。
