Constructing heterojunction between two semiconductors with matched energy band structure is an effective modification method to obtain excellent photocatalysts.The experimental scheme adopts a simple solvent method t...Constructing heterojunction between two semiconductors with matched energy band structure is an effective modification method to obtain excellent photocatalysts.The experimental scheme adopts a simple solvent method to self-assemble nitrogen doped carbon dots(N-CDs)on the surface of sulfur doped carbon nitride(S-C_(3)N_(4))semiconductor throughπ-πconjugate interaction.Based on this,a novel 0D/2D S-scheme heterojunction N-CDs/S-C_(3)N_(4)hybrid was successfully prepared.The degradation kinetic constants of N-CDs/S-C_(3)N_(4)for rhodamine B(RhB)and p-nitrophenol(PNP)reached 0.23522 and 0.01342 min^(−1),repectively,which were 2.72 and 2.65 times that of S-C_(3)N_(4).The highest photocatalytic hydrogen evolution rate was observed under the simulated sunlight irradiation,which was 2.30 times that of S-C_(3)N_(4).The improvement of photocatalytic performance was mainly based on the formation of the S-scheme heterojunction between S-C_(3)N_(4)and N-CDs.The effects of internal electric field,π-πconjugate interaction and band bending promoted the photogenerated h^(+)and e^(−) with low redox ability to recombine and retained the beneficial h+and e−with strong redox ability,which contributed to the production of more active species of h^(+) and•O_(2)−,therefore the photocatalytic degradation and hydrogen evolution performance were significantly enhanced.展开更多
基金support from the National Natural Science Foundation of China (Nos. 51962023, 51772139)the Natural Science Foundation of Jiangxi Province, China (No. 20192ACBL21047, 20212BAB204045)+1 种基金the Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle (Nanchang Hangkong University) (No. ES202002077)the 2019 Project of Liaoning Education Department (No. 2019LNJC20)
文摘Constructing heterojunction between two semiconductors with matched energy band structure is an effective modification method to obtain excellent photocatalysts.The experimental scheme adopts a simple solvent method to self-assemble nitrogen doped carbon dots(N-CDs)on the surface of sulfur doped carbon nitride(S-C_(3)N_(4))semiconductor throughπ-πconjugate interaction.Based on this,a novel 0D/2D S-scheme heterojunction N-CDs/S-C_(3)N_(4)hybrid was successfully prepared.The degradation kinetic constants of N-CDs/S-C_(3)N_(4)for rhodamine B(RhB)and p-nitrophenol(PNP)reached 0.23522 and 0.01342 min^(−1),repectively,which were 2.72 and 2.65 times that of S-C_(3)N_(4).The highest photocatalytic hydrogen evolution rate was observed under the simulated sunlight irradiation,which was 2.30 times that of S-C_(3)N_(4).The improvement of photocatalytic performance was mainly based on the formation of the S-scheme heterojunction between S-C_(3)N_(4)and N-CDs.The effects of internal electric field,π-πconjugate interaction and band bending promoted the photogenerated h^(+)and e^(−) with low redox ability to recombine and retained the beneficial h+and e−with strong redox ability,which contributed to the production of more active species of h^(+) and•O_(2)−,therefore the photocatalytic degradation and hydrogen evolution performance were significantly enhanced.
