Bespoke selenium nanowires with comprehensive piezo-phototronic effects as viable p-type semiconductor-based piezo-photocatalysts

Abstract

As the demand for environmental purification and energy harvesting continues to grow, research on maximizing the efficiency of catalysts is attracting great attention. The piezo-phototronic effect has emerged as an effective strategy to enhance the photocatalytic activity of semiconductors. While p-type semiconductors exhibit high photoresponsivity across a wide spectral range, their potential as piezo-photocatalysts has been limited due to their low carrier concentration and inferior carrier migration behavior. Therefore, it is hypothesized that overcoming these limitations would allow p-type semiconductors to achieve catalytic performance comparable to, or even surpassing, that of n-type systems. Here, we introduce two effective strategies into p-type trigonal selenium nanowires (Se NWs): electron-proton co-doping and localized surface plasmon resonance effect. These approaches improve the light absorption capacity, charge transport ability, and piezoelectricity, thereby significantly enhancing the piezo-photocatalytic performance. Under the influence of the piezo-phototronic effect, the post-treated Se NWs exhibit markedly enhanced evolution rates of reactive oxygen species compared to pure Se NWs. Consequently, the degradation efficiency of organic contaminants is increased up to 4-fold. This breakthrough opens up a new pathway for the development of p-type piezoelectric materials, which can potentially replace their n-type counterparts in catalytic applications. © 2023