Single‐Crystalline Nanomesh Tantalum Nitride Photocatalyst with Improved Hydrogen‐Evolving Performance

Tantalum nitride (Ta 3 N 5 ) with a suitable bandgap (≈2 eV) is regarded as one of the most promising photocatalysts for efficient solar energy harvesting and conversion. However, Ta 3 N 5 suffers from low hydrogen production activity due to the low carrier mobility and fast carrier recombination. Thus, the design of Ta 3 N 5 nanostructures to facilitate charge carrier transport and improve photocatalytic performance remains a challenge. This study reports a new type of ultrathin (≈2 nm) Ta 3 N 5 nanomesh with high specific surface area (284.6 m 2 g −1 ) and excellent crystallinity by an innovative bottom‐up graphene oxide templated strategy. The resulting Ta 3 N 5 nanomeshes demonstrate drastically improved electron transport ability and prolonged lifetime of charge carriers, due to the nature of high surface area and excellent crystallinity. As a result, when used as photocatalysts, the Ta 3 N 5 nanomeshes exhibit a greater than tenfold improvement in solar hydrogen production compared to bulk counterparts. This work provides an effective and generic strategy for designing 2D ultrathin nanomesh structures for nonlayered materials with improved catalytic activity.