Portable room-temperature self-powered/active H2 sensor driven by human motion through piezoelectric screening effect

Abstract

Room-temperature high H2 sensing has been realized from SnO2/ZnO nanoarray nanogenerator. Without any external electricity power source, the portable device can be self-powered under the driving of human motion, in which the piezoelectric output can actively act as both the power source and H2 sensing signal. Upon exposure to 800ppm H2 at room temperature, the piezoelectric output voltage of the device under the same applied deformation decreases from 0.80V (in dry air) to 0.14V, and the sensitivity is up to 471.4. The detection limit is ~10ppm H2, and the selectivity against H2 at room temperature is very high. The excellent room-temperature H2 sensing performance can be attributed to the coupling of the piezoelectric screening effect of ZnO nanowires and the conversion of SnO2/ZnO heterojunctions. This study can stimulate a research trend for the development of the next generation of portable room-temperature H2 sensors.