Katoch Akash, Sun Gun-Joo, Choi Sun-Woo, Hishita Shunichi, Kulish Vadym V, Wu Ping, Kim Sang Sub
Department of Materials Science and Engineering, Inha University, Incheon 402-751, Republic of Korea.
National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan.
Sci Rep. 2014 Apr 9;4:4622. doi: 10.1038/srep04622.
A new deep acceptor state is identified by density functional theory calculations, and physically activated by an Au ion implantation technique to overcome the high energy barriers. And an acceptor-compensated charge transport mechanism that controls the chemical sensing performance of Au-implanted SnO2 nanowires is established. Subsequently, an equation of electrical resistance is set up as a function of the thermal vibrations, structural defects (Au implantation), surface chemistry (1 ppm NO2), and solute concentration. We show that the electrical resistivity is affected predominantly not by the thermal vibrations, structural defects, or solid solution, but the surface chemistry, which is the source of the improved chemical sensing. The response and recovery time of chemical sensing is respectively interpreted from the transport behaviors of major and minor semiconductor carriers. This acceptor-compensated charge transport mechanism provides novel insights not only for sensor development but also for research in charge and chemical dynamics of nano-semiconductors.
通过密度泛函理论计算确定了一种新的深受体态，并通过金离子注入技术对其进行物理激活以克服高能垒。建立了一种控制金注入二氧化锡纳米线化学传感性能的受体补偿电荷传输机制。随后，建立了一个电阻方程，该方程是热振动、结构缺陷（金注入）、表面化学（1 ppm二氧化氮）和溶质浓度的函数。我们表明，电阻率主要不受热振动、结构缺陷或固溶体的影响，而是受表面化学的影响，表面化学是化学传感性能改善的来源。化学传感的响应和恢复时间分别从主要和次要半导体载流子的传输行为来解释。这种受体补偿电荷传输机制不仅为传感器开发，也为纳米半导体的电荷和化学动力学研究提供了新的见解。
