Engineering large-scaled electrochromic semiconductor films as reproductive SERS substrates for operando investigation at the solid/liquid interfaces

作者：Yang, Lingling; Feng, Jiuju; Wang, Jia-Ning; Gao, Zhida; Xu, Jingwen^*; Mei, Ye^*; Song, Yan-Yan^*

来源：CHINESE CHEMICAL LETTERS, 2022, 33(12): 5169-5173.

DOI：10.1016/j.cclet.2022.03.011

• Charge transfer
• Electrochromism
• Oxygen vacancies
• SERS substrate
• Solid/liquid interface

Although surface-enhanced Raman spectroscopy (SERS) has been applied for gathering fingerprint information, even in single molecule analysis, the decayed Raman signals in aqueous solutions largely obstruct the on-site insight reaction process. In this study, large-scaled semiconductor films with multiwalled (TiO2/WO3/TiO2) nanopore distribution are fabricated by combining electrochemical anodization and sputtering technique, and then employed as the SERS substrates for detection of molecules at the solid/liquid interfaces. Given the remarkably improved electrochromic property of the multi-walled film, such SERS substrates were endowed with tunable oxygen vacancy (V-O) density and distribution via simply applying electrochemical bias voltage, which enabled one to achieve an enhanced charge transfer efficiency and thus a remarkably increased Raman signal even in solution. The V-O-rich SERS substrate is highly repeatable, thus providing a reliable platform for in-situ monitoring of the target molecules or intermediates at the solid/liquid interfaces.

• 单位
  浙江师范大学; y; 东北大学