Tailoring TiO2 Nanotube-Interlaced Graphite Carbon Nitride Nanosheets for Improving Visible-Light-Driven Photocatalytic Performance

Abstract

Rapid recombination of photoinduced electron–hole pairs is one of the major defects in graphitic carbon nitride (g-C3N4)-based photocatalysts. To address this issue, perforated ultralong TiO2 nanotube-interlaced g-C3N4 nanosheets (PGCN/TNTs) are prepared via a template-based process by treating g-C3N4 and TiO2 nanotubes polymerized hybrids in alkali solution. Shortened migration distance of charge transfer is achieved from perforated PGCN/TNTs on account of cutting redundant g-C3N4 nanosheets, leading to subdued electron–hole recombination. When PGCN/TNTs are employed as photocatalysts for H2 generation, their in-plane holes and high hydrophilicity accelerate cross-plane diffusion to dramatically promote the photocatalytic reaction in kinetics and supply plentiful catalytic active centers. By having these unique features, PGCN/TNTs exhibit superb visible-light H2-generation activity of 1364 µmol h−1 g−1 (λ > 400 nm) and a notable quantum yield of 6.32% at 420 nm, which are much higher than that of bulk g-C3N4 photocatalysts. This study demonstrates an ingenious design to weaken the electron recombination in g-C3N4 for significantly enhancing its photocatalytic capability.