Engineering electronic bridge and Schottky modulation via strontium hydroxide nanoparticles on g-C3N4/Ti3C2 for excellent photocatalytic H2 production and CO2 reduction

Advanced two-dimensional nanomaterials open new pathways for efficient photocatalysis, driving progress in environmental protection and renewable energy applications. However, the photocatalytic activity of conventional Schottky-based heterojunctions remains limited due to poor charge separation and high Schottky barrier height. To overcome these challenges, we developed a novel heterojunction comprising two-dimensional graphitic carbon nitride (CN), titanium carbide (TC), and strontium hydroxide (Sr(OH)2 is abbreviated as SrO) nanoparticles through a cost-effective approach to enhance photocatalytic efficiency. The CN/SrO-2/TC photocatalyst exhibits a 2.71 eV band gap and enhanced porosity, boosting its visible light absorption. Introducing precise amounts of strontium hydroxide into titanium carbide and graphitic carbon nitride nanosheets significantly enhances structural stability and photocatalytic efficiency by promoting efficient interfacial contact and electron mobility. The reduction of the Schottky barrier height from 2.54 eV to 1.38 eV in CN/SrO/TC enhances interfacial charge dynamics and suppresses electron-hole recombination, thereby improving photocatalysis. The strong interfacial bonding of Sr-Ti-C and Sr-C-N linkages and the synergistic effect of oxygen and nitrogen vacancies further promote the formation of •O2− and •OH radicals, accelerating redox reactions. This advanced photocatalyst achieves exceptional results, with a carbon monoxide (CO) yield rate of 225.5 μmol g−1 h−1 and hydrogen (H2) production 18700 μmol g−1 h−1. Notably, it achieves 99.3 % Rhodamine B (RhB) degradation in 90 min and 99.6 % Tetracycline (TC) degradation in 60 min. The novelty of this work lies in engineering electronic bridges via Sr(OH)2 nanoparticles to precisely tune interfacial charge distribution and Schottky barrier height, which has not been previously reported for CN/TC systems. This study provides a new strategy for designing cost-effective and stable heterostructures to address global challenges in clean energy production and environmental remediation.