A self-powered inert-gas sensor based on gas ionization driven by a triboelectric nanogenerator

Abstract

Inert gases play an important role in fabrication technologies and human life activities. However, normal gas-detection methods have many limitations on the costs and operation to detect inert gases since inert gases have extremely inactive chemical properties. In this paper, a self-powered inert-gas sensor based on gas discharges induced by a rotating triboelectric nanogenerator (TENG) with a needle discharge structure is developed. The friction layers of the rotating TENG are optimized to generate a high-voltage output with a sufficient pulse width for gas ionization in the high electric field formed between the small gap of two needle tips. Because different inert gases have different ionization characteristics, the type, pressure, and concentration of inert gases can be distinguished from TENG voltage gains during ionization. The experimental results indicate that, at standard atmospheric pressure, the gain of the TENG open-circuit voltage is 250% when ionizing air, 330% for ionizing argon, and 180% for ionizing helium. When ionizing a specific gas, both a decrease in pressure and an increase in concentration result in an increase in open-circuit voltage gain. Based on correlation between the types, pressure and concentration of gas and the output performance of TENG, the inert gas sensor with simple operation and high efficiency can be realized. The proposed inert gas sensor is simple, low cost and self-powered, which has potential applications in the field of industry and the Internet of Things (IoT).