Controllable Interface‐Induced Co‐Assembly toward Highly Ordered Mesoporous Pt@TiO2/g‐C3N4 Heterojunctions with Enhanced Photocatalytic Performance

Abstract Titania‐based materials have aroused great attention in energy conversion and photocatalytic degradation, but they suffer from the drawbacks of fast electron–hole recombination and narrow light‐adsorption range. Here, a series of heterojunction mesoporous TiO 2 /g‐C 3 N 4 (mTiO 2 /g‐C 3 N 4 ) composites with improved light‐adsorption capacity and efficient light‐capturing property are designed through a novel solid–liquid interface induced co‐assembly strategy and controlling the interface property of g‐C 3 N 4 . Through introducing Pt precursor during the synthesis, ultrasmall Pt nanoparticles are in situ generated in the mTiO 2 /g‐C 3 N 4 composites, forming mesoporous Pt@TiO 2 /g‐C 3 N 4 (mPt @ TiO 2 /g‐C 3 N 4 ‐4.0) with abundant surface active sites, and huge heterojunction interfaces. The obtained mPt @ TiO 2 /g‐C 3 N 4 ‐4.0 photocatalysts have narrow band gap (≈2.96 eV) and superior performance in promoting separation of photogenerated charge carriers. They show ultrahigh photocurrent density (≈8.3 µA cm −2 ) that is five times higher than that of mTiO 2 /g‐C 3 N 4 ‐4.0 (≈1.6 µA cm −2 ) due to the effective charge separation between the semiconductors and Pt nanoparticles, as well as the synergistic effect at heterojunction interfaces. In addition, mPt @ TiO 2 /g‐C 3 N 4 photocatalysts show excellent performance in photodegradation of rhodamine B with fast decomposition rate within 8 min. These results foresee the wide‐range applications of the composite photocatalysts potential candidates for solar‐to‐fuel conversion and environmental remediation.