Tunable Schottky barrier height of a Pt–CuO junction via a triboelectric nanogenerator

Tuning Schottky barrier height is crucial to optimize the performance of Schottky junction devices. Here, we demonstrate that the Schottky barrier height can be tuned with the voltage from a triboelectric nanogenerator (TENG). Schottky barrier heights at both ends are increased after the treatment with the voltage generated by the TENG. The electric field generated by the impulse voltage of the TENG drives the diffusion of the ionized oxygen vacancy in a CuO nanowire, which induces the nonuniform distribution of the ionized oxygen vacancy. The positively charged oxygen vacancy accumulates at the contacted interface of Pt and the CuO nanowire, and it impels the conduction and valence bands to bend downwards. The Schottky barrier height is raised. A theoretical model based on the energy band diagram is proposed to explain this phenomenon. This method offers a simple and effective avenue to tune the Schottky barrier height. It opens up the possibility to develop a high-performance Schottky sensor by tuning the Schottky barrier height.