Surface Chemistry Laboratory of Electronic Materials, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
Department of Chemical and Materials Engineering, College of Engineering, Chang Gung University, Taoyuan, 33302, Taiwan.
Adv Mater. 2023 Jan;35(4):e2200172. doi: 10.1002/adma.202200172. Epub 2022 Mar 11.
A Z-scheme heterojunction with spatially separated cocatalysts is proposed for overcoming fundamental issues in photocatalytic water splitting, such as inefficient light absorption, charge recombination, and sluggish reaction kinetics. For efficient light absorption and interfacial charge separation, Z-scheme organic/inorganic heterojunction photocatalysts are synthesized by firmly immobilizing ultrathin g-C N on the surface of TiO hollow spheres via electrostatic interactions. Additionally, two cocatalysts, Pt and IrO , are spatially separated along the Z-scheme charge-transfer pathway to enhance surface charge separation and reaction kinetics. The as-prepared Pt/g-C N /TiO /IrO (PCTI) hollow sphere photocatalyst exhibits an exceptional H evolution rate of 8.15 mmol h g and a remarkable apparent quantum yield of 24.3% at 330 nm in the presence of 0.5 wt% Pt and 1.2 wt% IrO cocatalysts on g-C N and TiO , respectively. Photoassisted Kelvin probe force microscopy is used to systematically analyze the Z-scheme charge-transfer mechanism within PCTI. Furthermore, the benefits of spatially separating cocatalysts in the PCTI system are methodically investigated in comparison to randomly depositing them. This work adequately demonstrates that the combination of a Z-scheme heterojunction and spatially separated cocatalysts can be a promising strategy for designing high-performance photocatalytic platforms for solar fuel production.
提出了一种具有空间分离共催化剂的 Z 型异质结，以克服光催化水分解中的一些基本问题，如光吸收效率低、电荷复合和反应动力学缓慢。为了实现有效的光吸收和界面电荷分离，通过静电相互作用将超薄 g-CN 牢固地固定在 TiO 空心球表面，合成了 Z 型有机/无机异质结光催化剂。此外，沿 Z 型电荷转移途径将两个共催化剂（Pt 和 IrO）空间分离，以增强表面电荷分离和反应动力学。所制备的 Pt/g-CN/TiO/IrO（PCTI）空心球光催化剂在 0.5 wt% Pt 和 1.2 wt% IrO 共催化剂分别负载在 g-CN 和 TiO 上时，在 330nm 光照下表现出 8.15mmol h g 的出色 H 2 演化速率和 24.3%的显著表观量子效率。光辅助 Kelvin 探针力显微镜被用于系统地分析 PCTI 中的 Z 型电荷转移机制。此外，还将空间分离共催化剂在 PCTI 系统中的优势与随机沉积共催化剂的优势进行了系统的比较研究。这项工作充分证明了 Z 型异质结和空间分离共催化剂的结合可以成为设计用于太阳能燃料生产的高性能光催化平台的一种很有前途的策略。
