油浸式变压器内微水在Zn改性C空位C_(3)N的吸附传感特性及电子行为研究

Adsorption Sensing Characteristics and Electronic Behaviors of Water on Zn-Modified C-Vacancy C_(3)N Inside Oil-Immersed Transformers

油浸式变压器的含水量直接决定着变压器的绝缘水平和使用寿命,保证变压器安全稳定运行,对水分子(H_(2)O)传感器的可靠性提出了新的要求。基于泛函密度理论计算(DFT),分析了过渡金属纳米Zn粒子对二维材料C_(3)N的表面改性效应。在对本征C_(3)N、C空位C_(3)N,及Zn原子掺杂C_(3)N对H_(2)O分子的吸附能力进行比较后,发现掺杂后的吸附能分别为本征(-0.231 eV)及C空位C_(3)N(-0.550 eV)的3.52倍和1.48倍。Zn原子能够在维持原有C_(3)N化学结构稳定性的同时,提高复合结构的导电性。结果表明,掺杂原子的附着改善了C_(3)N单层对变压器中H_(2)O吸附时的电子行为。吸附类型从物理吸附转变为化学吸附,理想的吸附能(-0.814 eV)使掺杂系统拥有良好的吸附和解吸性能。本研究为进一步应用变压器H_(2)O分子传感器,实现绝缘设备的在线监测提供了理论依据。

The water content of oil-immersed transformers direct determines the insulation level and service life of transformers,and ensuring the safe and stable operation of transformers puts forward new requirements on the reliability of water molecule(H_(2)O)sensors.The surface modification effect of transition metal nano-Zn particle on the two-dimensional material C_(3)N is analyzed based on the calculation of the density functional theory(DFT).The adsorption abilities of pristine C_(3)N,C-vacancy C_(3)N,and Zn atom-doped C_(3)N on H_(2)O molecules are compared,and the results show that the adsorption energy after doping is 3.52 and 1.48 times higher than that of pristine(-0.231 eV)and C-vacancy C_(3)N(-0.550 eV),respectively.The Zn atom can improve the electrical conductivity of the composite structure while maintaining the stability of the original C_(3)N chemical structure.The attachment of doped atom improves the electronic behavior of C_(3)N monolayers during the adsorption of H_(2)O from transformers.The adsorption type changes from physical to chemical adsorption,and the ideal adsorption energy(-0.814 eV)demonstrates the good adsorption and desorption properties of the doped system.This study provides a theoretical basis for further application of transformer H_(2)O sensors on online monitoring of insulated equipment.