Yuan Tian, Fu Chao, Gong Yujia, Tong Yue, Zhang Jin, Wang Yuqing
China Electric Power Research Institute, Wuhan 430074, China.
ACS Omega. 2021 Jul 14;6(29):19127-19133. doi: 10.1021/acsomega.1c02474. eCollection 2021 Jul 27.
This work using first-principles theory studies the sensing properties of Cu-decorated GaN (Cu-GaN) monolayers as a promising candidate for the detection of CO and HCHO in dry-type transformers. The Cu dopant prefers to be trapped on the T site of the GaN surface with an of -1.13 eV. Chemisorption is identified for the two gas adsorption systems, given the large adsorption energy ( ) of -1.35 and -1.09 eV. Caused by the chemisorption, the electronic property of the Cu-GaN monolayer is significantly deformed, narrowing its band gap of 0.548 eV to 0.00 eV, exhibiting metallic property, in two gas systems. Combined with the desirable recovery property for CO and HCHO desorption from the Cu-GaN surface, it could be proposed that the Cu-GaN monolayer is a promising gas sensor for toxic gas detection in dry-type transformers, so as to evaluate the operation status of the power system and guarantee safe working conditions for the maintenances.
这项工作运用第一性原理理论研究了铜修饰氮化镓（Cu-GaN）单层作为干式变压器中一氧化碳和甲醛检测的潜在候选材料的传感特性。铜掺杂剂倾向于捕获在氮化镓表面的T位，形成能为-1.13电子伏特。鉴于两种气体吸附系统的大吸附能（分别为-1.35和-1.09电子伏特），确定为化学吸附。化学吸附导致Cu-GaN单层的电子性质发生显著变形，在两种气体系统中，其带隙从0.548电子伏特缩小到0.00电子伏特，呈现出金属特性。结合一氧化碳和甲醛从Cu-GaN表面解吸的良好恢复特性，可以认为Cu-GaN单层是用于干式变压器有毒气体检测的有前景的气体传感器，从而评估电力系统的运行状态并确保维护工作的安全工作条件。
