Ma Nan, Suematsu Koichi, Yuasa Masayoshi, Kida Tetsuya, Shimanoe Kengo
§Department of Applied Chemistry and Biochemistry, Kumamoto University, Kumamoto 860-8555, Japan.
ACS Appl Mater Interfaces. 2015 Mar 18;7(10):5863-9. doi: 10.1021/am509082w. Epub 2015 Mar 9.
The effect of water vapor on Pd-loaded SnO2 sensor was investigated through the oxygen adsorption behavior and sensing properties toward hydrogen and CO under different humidity conditions. On the basis of the theoretical model reported previously, it was found that the mainly adsorbed oxygen species on the SnO2 surface in humid atmosphere was changed by loading Pd, more specifically, for neat SnO2 was O(-), while for 0.7% Pd-SnO2 was O(2-). The water vapor poisoning effect on electric resistance and sensor response was reduced by loading Pd. Moreover the sensor response in wet atmosphere was greatly enhanced by loading Pd. It seems that the electron depletion layer by p-n junction of PdO-SnO2 may impede OH(-) adsorption.
通过在不同湿度条件下的氧吸附行为以及对氢气和一氧化碳的传感特性，研究了水蒸气对负载钯的二氧化锡传感器的影响。基于先前报道的理论模型，发现通过负载钯，在潮湿气氛中二氧化锡表面主要吸附的氧物种发生了变化，更具体地说，对于纯二氧化锡是O(-)，而对于0.7%钯-二氧化锡是O(2-)。负载钯降低了水蒸气对电阻和传感器响应的中毒效应。此外，负载钯极大地增强了潮湿气氛中的传感器响应。似乎PdO-SnO2的p-n结形成的电子耗尽层可能会阻碍OH(-)的吸附。
