Turning on Selective H2S Gas Sensing Activity in Ternary Nickel Tungstate Strongly Correlated Electron System Through Sub‐Gap Band Manipulation

• DOI: 10.1002/adfm.202425477
• Publication Date: 2025-03-10T20:51:11Z
• Authors: Seung Yong Lee; Ha Eun Choa; Seung Joon Choi; Chul Oh Park; Gi Hyun Park; June Won Suh; Si Hoon Jeong; Yunseong Ji; Changhyun Jin; Jeong Yun Hwang; Inseo Kim; Jihye Park; Joonho Bang; Myung Sik Choi; Hyo‐Jick Choi; Dong Won Chun; Kimoon Lee; Wooyoung Lee; Kyu Hyoung Lee
• Keywords: Tungstate; Ternary numeral system

Abstract Sensing the precise concentration of chemicals within a complex atmosphere stands as critical technology with far‐reaching implications in environmental, agricultural, and medical domains. While sensitivity limits are pushed down to ppb levels through diverse material tuning approaches, ensuring robust selectivity for targeted analyte gases remains challenge due absence effective methodologies. Here, band structure modulation is presented selective detection H 2 S utilizing NiWO 4 ‐based compound, achieved strategically manipulating sub‐gap states. The approach involves tailoring by employing point defect engineering mechanisms Cu substitutional Li interstitial doping. Unlike featureless pristine Cu‐doped , Li/Cu‐co‐doped exhibits sensing response gas, exhibiting an approximately six‐fold increase sensitivity. Through density functional theory calculations Mott–Schottky analysis, it unveiled that this high toward stem from generation positioning d ‐orbital‐derived states, matching reduction potential S, which triggered presence Li. This result suggests novel strategy customizing materials based on gases.