The integration of carbon dots(CDs)with graphitic carbon nitride(g-C_(3)N_(4))has emerged as a promising approach to enhance photocatalytic hydrogen(H_(2))evolution.Despite significant progress,critical challenges rem...The integration of carbon dots(CDs)with graphitic carbon nitride(g-C_(3)N_(4))has emerged as a promising approach to enhance photocatalytic hydrogen(H_(2))evolution.Despite significant progress,critical challenges remain in achieving broad visiblelight absorption and suppressing charge recombination.In this work,we developed a series of photocatalysts through in situ embedding of red-emissive CDs(R-CDs)into g-C_(3)N_(4)(RCN)with precisely controlled loading amounts.Systematic characterization revealed that the R-CDs incorporation simultaneously addresses two fundamental limitations:(1)extending the light absorption edge to 800 nm,and(2)acting as an electron acceptor,facilitating charge separation.The optimized RCN composite demonstrates exceptional H_(2)evolution activity(1.87 mmol·g^(-1)·h^(-1),wavelength(λ)≥420 nm),representing a 3.3-fold enhancement over pristine g-C_(3)N_(4).Remarkably,the apparent quantum efficiency(AQE)reaches 9.1% at 420 nm,while maintaining measurable activity beyond 475 nm,where unmodified g-C_(3)N_(4)shows negligible response.This study provides fundamental insights into band structure engineering and charge carrier management through rational design of CDs-modified semiconductor heterostructures.展开更多
基金financially supported by the National Key R&D Program of China(No.2023YFB3810800)the National Natural Science Foundation of China(Nos.22579008,22502012,22301013,and 22272003)+3 种基金Key Project of the National Natural Science Foundation of China(No.21936001)R&D Program of Beijing Municipal Education Commission(No.KZ20231000506)Beijing Outstanding Young Scientists Program(No.BJJWZYJH01201910005017)the Project of Construction of Innovative Teams and Teacher Career Development for Universities and Colleges Under Beijing Municipality(No.11000024T000003219982).
文摘The integration of carbon dots(CDs)with graphitic carbon nitride(g-C_(3)N_(4))has emerged as a promising approach to enhance photocatalytic hydrogen(H_(2))evolution.Despite significant progress,critical challenges remain in achieving broad visiblelight absorption and suppressing charge recombination.In this work,we developed a series of photocatalysts through in situ embedding of red-emissive CDs(R-CDs)into g-C_(3)N_(4)(RCN)with precisely controlled loading amounts.Systematic characterization revealed that the R-CDs incorporation simultaneously addresses two fundamental limitations:(1)extending the light absorption edge to 800 nm,and(2)acting as an electron acceptor,facilitating charge separation.The optimized RCN composite demonstrates exceptional H_(2)evolution activity(1.87 mmol·g^(-1)·h^(-1),wavelength(λ)≥420 nm),representing a 3.3-fold enhancement over pristine g-C_(3)N_(4).Remarkably,the apparent quantum efficiency(AQE)reaches 9.1% at 420 nm,while maintaining measurable activity beyond 475 nm,where unmodified g-C_(3)N_(4)shows negligible response.This study provides fundamental insights into band structure engineering and charge carrier management through rational design of CDs-modified semiconductor heterostructures.
