Facile "Spot-Heating" Synthesis of Carbon Dots/Carbon Nitride for Solar Hydrogen Evolution Synchronously with Contaminant Decomposition

The use of solar energy to produce the clean hydrogen (H-2) energy from water splitting is a promising means of renewable energy conversion. High activation barriers for O-2 generation associated with the rate-limiting steps require utilization of noble metal-based cocatalysts, which complicates the fabrication procedure and compromises the stability of the catalyst. Here, a homogenous "spot heating" approach is designed via the ultrasonic cavitation effect for evenly embedding highly crystalline carbon quantum dots (CQDs) on 2D C3N4 nanosheets. Based on density functional calculations and electrochemical experiments, the optimal introduction of CQDs into C3N4 not only extends light absorption spectrum, but also reduces effective mass of electrons (e(-)), facilitating photocarrier transport from excited sites. And, more importantly, the well-organized CQDs with superior peroxidase mimetic activity can increase catalytic H-2 production through the process of (i) 2H(2)O -> H2O2 + H-2; (ii) H2O2 -> 2 center dot OH; (iii) center dot OH + bisphenol A. Final Products, with H-2 production rate (152 mu mol g(-1) h(-1)) several times higher than that for pure C3N4. This work demonstrates an ideal platform for efficient H-2 production with synergetic organic contaminant degradation, thereby opening possibilities for coupling energy conversion with environmental remediation.