Photocatalytic water splitting is one of the sustainable and environmentally-friendly methods for producing hydrogen.Bulk C_(3)N_(4) shows promise in the photocatalytic production of H2,but its activity is greatly lim...Photocatalytic water splitting is one of the sustainable and environmentally-friendly methods for producing hydrogen.Bulk C_(3)N_(4) shows promise in the photocatalytic production of H2,but its activity is greatly limited by low number of reactive sites.Herein,Ni-doped porous honeycomb C_(3)N_(4)(Ni/HCN-V_(N))was prepared for photocatalytic hydrogen production using a morphology modulation method followed by rapid Joule heating treatment.The porous honeycomb structure could expose more reactive sites and improve light utilization.Compared to the traditional calcination method,the Joule heating method well retained the honeycomb structure,which gave Ni/HCN-V_(N) a higher specific surface area(33.2 m^(2) g^(-1)),approximately 3.2 times higher than that of bulk C_(3)N_(4)(10.3 m^(2) g^(-1)).Moreover,the introduction of Ni along with the generated nitrogen vacancies(during the Joule heating treatment)provided more reactive sites,further improving the photocatalytic activity.Experimental and theoretical calculations indicated that fast charge transfer between the metal(Ni)and the substrate(C_(3)N_(4))occured,and the dual active sites(Ni and nitrogen vacancies)would strengthen the adsorption of H2O and desorption of H2.Overall,as-prepared Ni/HCN-V_(N) exhibited a high photocatalytic H2 production rate(420.02μmol g^(-1) h^(-1)).This work provides a rapid synthesis strategy for the preparation of porous honeycomb C_(3)N_(4) with rich defective sites and metal doping,and will make an important contribution to the structural design and modulation of photocatalytic properties.展开更多
基金supported by the Shandong Provincial Natural Science Foundation(Grant No.ZR2021QB056)the Fundamental Research Funds for the Central Universities(No.202261014)the Taishan Scholars Foundation of Shandong province(No.tsqn201909058).
文摘Photocatalytic water splitting is one of the sustainable and environmentally-friendly methods for producing hydrogen.Bulk C_(3)N_(4) shows promise in the photocatalytic production of H2,but its activity is greatly limited by low number of reactive sites.Herein,Ni-doped porous honeycomb C_(3)N_(4)(Ni/HCN-V_(N))was prepared for photocatalytic hydrogen production using a morphology modulation method followed by rapid Joule heating treatment.The porous honeycomb structure could expose more reactive sites and improve light utilization.Compared to the traditional calcination method,the Joule heating method well retained the honeycomb structure,which gave Ni/HCN-V_(N) a higher specific surface area(33.2 m^(2) g^(-1)),approximately 3.2 times higher than that of bulk C_(3)N_(4)(10.3 m^(2) g^(-1)).Moreover,the introduction of Ni along with the generated nitrogen vacancies(during the Joule heating treatment)provided more reactive sites,further improving the photocatalytic activity.Experimental and theoretical calculations indicated that fast charge transfer between the metal(Ni)and the substrate(C_(3)N_(4))occured,and the dual active sites(Ni and nitrogen vacancies)would strengthen the adsorption of H2O and desorption of H2.Overall,as-prepared Ni/HCN-V_(N) exhibited a high photocatalytic H2 production rate(420.02μmol g^(-1) h^(-1)).This work provides a rapid synthesis strategy for the preparation of porous honeycomb C_(3)N_(4) with rich defective sites and metal doping,and will make an important contribution to the structural design and modulation of photocatalytic properties.
