Novel insight into charge transfer regulation based on carrier density-dependent Ag/ITO composite films

Yang Jin; Eungyeong Park; Chenghao Tang; Qi Chu; Sila Jin; Shuang Guo; Lei Chen; Young Mee Jung

doi:10.1016/j.saa.2022.121236

Novel insight into charge transfer regulation based on carrier density-dependent Ag/ITO composite films

Spectrochim Acta A Mol Biomol Spectrosc. 2022 Aug 5:276:121236. doi: 10.1016/j.saa.2022.121236. Epub 2022 Apr 5.

Authors

Yang Jin¹, Eungyeong Park², Chenghao Tang¹, Qi Chu¹, Sila Jin³, Shuang Guo², Lei Chen⁴, Young Mee Jung⁵

Affiliations

¹ Key Laboratory of Preparation and Applications of Environmental Friendly Materials, Ministry of Education, College of Chemistry, Jilin Normal University, Changchun 130103, PR China.
² Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University, Chuncheon 24341, Republic of Korea.
³ Kangwon Radiation Convergence Research Support Center, Kangwon National University, Chuncheon 24341, Republic of Korea.
⁴ Key Laboratory of Preparation and Applications of Environmental Friendly Materials, Ministry of Education, College of Chemistry, Jilin Normal University, Changchun 130103, PR China. Electronic address: chenlei@jlnu.edu.cn.
⁵ Department of Chemistry, Institute for Molecular Science and Fusion Technology, Kangwon National University, Chuncheon 24341, Republic of Korea; Kangwon Radiation Convergence Research Support Center, Kangwon National University, Chuncheon 24341, Republic of Korea. Electronic address: ymjung@kangwon.ac.kr.

PMID: 35405377
DOI: 10.1016/j.saa.2022.121236

Abstract

Cosputtering technology was utilized to prepare a Ag and indium tin oxide (ITO) composite on a flat polystyrene (PS) microsphere array. The carrier density estimated by Hall effect testing of different Sn concentrations in the cosputtered films can be tuned from 10¹⁸ to 10²⁰ cm^-3. The bandgap calculated based on ultraviolet photoelectron spectroscopy can be adjusted within the range of 3.95-4.02 eV. We explored the possible mechanism of charge transfer (CT) by varying the bandgap and explained the causes of the surface-enhanced Raman scattering (SERS). Surprisingly, a synchronous change in the CT process with the carrier density was discovered. This observation suggests that the CT process can be precisely regulated by changes in the composition of the metal-semiconductor nanostructures. Our study provides a reference for the application of Ag/ITO films as alternative near-infrared plasmonic materials.

Keywords: Ag/ITO film; CT; Carrier density; Cosputtering; SERS.