Piezo/active humidity sensing of CeO_2/ZnO and SnO_2/ZnO nanoarray nanogenerators with high response and large detecting range

摘要

Piezo/active humidity sensing of CeO_2/ZnO and SnO_2/ZnO nanoarray nanogenerators with high response and large detecting range have been realized. The piezoelectric output of the devices under external deformation is extremely sensitive to the humidity with a very large detecting range. The piezoelectric output of the devices can act not only as a power source, but also as a response signal to the relative humidity of the ambience. Such behavior can be attributed to the piezotronic effect of ZnO nanowires and the surface modification of CeO_2 or SnO_2 nanoparticles. Our study can open a new way for actively detecting humidity in the environment.