Electrical Transport Property of ZnO Thin Films in High H2 Pressure up to 20 bar

TL;DR

This study examines how high-pressure hydrogen affects the electrical conductance of ZnO thin films, revealing a peak at 2 bar due to H2 spillover effects, with implications for gas sensing applications.

Contribution

It provides new insights into the pressure-dependent electrical behavior of ZnO thin films and highlights the role of H2 spillover in conductance variation.

Findings

Conductance peaks at 2 bar H2 pressure

H2 spillover significantly influences conductance changes

Conductance decreases monotonically beyond 2 bar H2

Abstract

We have investigated the H2 pressure-dependent (from vacuum to 20 bar) current-voltage characteristics of ZnO thin films prepared by spin coating method. The gas pressure effect on conductance (G) was subtracted using He gas. The G increased as applying 2 bar of H2 pressure, and then it monotonously decreased with the further increment of H2 pressure. Using X-ray diffraction patterns and X-ray photoelectron spectroscopy before and after H2 exposure, we found that the H2 spillover effect plays an important role in the variation of G of ZnO film.