Nitrogen-doped carbon-wrapped C,N-codoped TiO2 (CN@C,N-TiO2) was successfully prepared using a facile and efficient method involving hydrolysis and calcination under Ar using tetrabutyl titanate and 2,6-diaminopyridine as the precursors. X-ray photoelectron spectroscopy (XPS) and valence band XPS measurements reveal the successful codoping of interstitial carbon and nitrogen into TiO2, which leads to a visible-light absorption of up to ∼550 nm in the UV–vis diffuse reflectance spectra. Raman spectra and high-resolution transmission electron microscopy results show that N-doped carbon exists on the surface of C,N-TiO2, which gives rise to the efficient separation of photoexcited charge carriers, as determined by photoluminescence and electrochemical impedance spectroscopy. Benefiting from the combined effects of a surface-coated N-doped carbon layer and C,N-codoping, the photocatalyst calcined at 450 °C exhibits remarkable visible-light activity toward the hydrogen evolution reaction in the water splitting process with a H2 production rate of 833.2 μmol h–1 g–1 under 94 mW cm–2 visible-light illumination (λ > 420 nm). Moreover, the representative CN@C,N-TiO2 sample can maintain its activity for at least 40 h.

The exploration of low-cost, high-performance, and stable photocatalysts for the highly efficient conversion and storage of solar energy in hydrogen is of great importance. This study presents a novel pyridine-type carbonitrides (CN)-modified surface-disordered C-doped TiO2 (PCN/CTiO2@TiO2–x ) catalyst used for photocatalytic H2 evolution from water. The employed preparation method of hydrolysis–calcination has the advantages of low-cost raw materials and easy scale-up. The optimized PCN/CTiO2@TiO2–x exhibited an impressive hydrogen evolution rate of ∼3743 μmol h–1 g–1 under simulated solar light (AM 1.5) and remained stable after five cycles. The maximal quantum efficiency reached 37.5% at 370 nm and 7.0% at 400 nm, which was superior or comparable to several reported relevant TiO2-based catalysts. Benefiting from the pyridine-type CN modification, disordered surface layer (TiO2–x ), and increased oxygen vacancies/Ti3+ species, the photogenerated electrons moved rapidly from the visible-response C-doped TiO2 to CN to participate in the photoreduction reaction, which led to a marked improvement in the catalytic activity.