Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
Sci Rep. 2023 Mar 28;13(1):5019. doi: 10.1038/s41598-023-32210-6.
Several in-situ electrochemical approaches have been developed for performing a localized photoelectrochemical investigation of the photoanode. One of the techniques is scanning electrochemical microscopy (SECM), which probes local heterogeneous reaction kinetics and fluxes of generated species. In traditional SECM analysis of photocatalysts, evaluation of the influence of radiation on the rate of studied reaction requires an additional dark background experiment. Here, using SECM and an inverted optical microscope, we demonstrate the determination of O flux caused by light-driven photoelectrocatalytic water splitting. Photocatalytic signal and dark background are recorded in a single SECM image. We used an indium tin oxide electrode modified with hematite (α-FeO) by electrodeposition as a model sample. The light-driven flux of oxygen is calculated by analysis of SECM image recorded in substrate generation/tip collection mode. In photoelectrochemistry, the qualitative and quantitative knowledge of oxygen evolution will open new doors for understanding the local effects of dopants and hole scavengers in a straightforward and conventional manner.
已经开发了几种原位电化学方法来对光电阳极进行局部光电化学研究。其中一种技术是扫描电化学显微镜（SECM），它可以探测局部非均相反应动力学和生成物质的通量。在传统的光催化剂 SECM 分析中，评估辐射对研究反应速率的影响需要进行额外的暗背景实验。在这里，我们使用 SECM 和倒置光学显微镜，展示了光驱动光电催化水分解引起的 O 通量的确定。在单个 SECM 图像中记录光催化信号和暗背景。我们使用通过电沉积修饰有赤铁矿（α-FeO）的氧化铟锡电极作为模型样品。通过在基底产生/尖端收集模式下记录的 SECM 图像分析，计算光驱动的氧气通量。在光电化学中，对氧气析出的定性和定量知识将为以直接和传统的方式理解掺杂剂和空穴清除剂的局部效应开辟新的途径。
