Etched p-Type Si Nanowires for Efficient Ozone Decomposition

Abstract

High concentration ozone can damage greatly to the respiratory, cardiovascular systems, and fertility of people, and catalytic decomposition is an important strategy to reduce its harm. However, it remains a challenge to develop efficient ozone decomposition catalysts with high efficiency. In this study, p- and n-type silicon nanowires (Si NWs) are fabricated by wet chemical etching method and are firstly applied to catalytic decompose ozone at room temperature. The p-type Si NWs exhibit 90% ozone (20 ppm O3/air) decomposition efficiency with great stability, which is much better than that of n-type Si NWs (50%) with same crystal orientation, similar diameter and specific surface area. The catalytic property difference is mainly attributed to the more delocalization holes in the p-type Si NWs, which can accelerate the desorption of ozone decomposition intermediates (i.e., adsorbed oxygen species).

Impacts of Wafer Doping Type on Structural and Optical Properties of Black Silicon Fabricated by Metal-Assisted Chemical Etching

“…Furthermore, Li et al conducted comparable studies, concluding that n-type wafers contain much more electrons than p-type wafers. Because the n-type wafers have a higher oxidation rate than the p-type wafers, the etching reaction rate is more rapid, and the length of the b-Si NWs is longer for n-type than for p-type b-Si NWs with the same etching duration [11]. Apart from wafer type, the doping level of the wafer has been found to influence the morphology of the etched structures [7,12].…”