Development of low-cost and efficient photocatalytic materials with visible-light response is of urgent need for solving energy and environmental problems.Here,a metal-free two-dimensional(2D)π-conjugated hybrid g-C_...Development of low-cost and efficient photocatalytic materials with visible-light response is of urgent need for solving energy and environmental problems.Here,a metal-free two-dimensional(2D)π-conjugated hybrid g-C_(3)N_(4)photocatalyst with tunable band structure was prepared by a novel one-pot bottom-up method based on a supersaturated precipitation process of urea and triethanolamine(TEOA)solution.The microstructure of the hybrid g-C_(3)N_(4)is revealed to be a compound of periodic tri-s-triazine units grafted with N-doped graphene(GR)fragments.From experimental evidence and theoretical calculations,the two differentπ-conjugated fragments in the hybrid g-C_(3)N_(4)material are proved to construct a 2D in-plane junction structure,thereby expanding the light absorption range and accelerating the interface charge transfer.Theπ-conjugated electron coupling in the 2D photocatalyst eliminates the grain boundary effect,and the coupled highest occupied molecular orbital(HOMO)effectively promotes the separation of photo-induced charge carriers.Compared with the g-C_(3)N_(4)prepared by the conventional method,the visible-light H2 production activity of the optimized sample is enhanced by 253%.This work provides a new strategy of constructing metal-free g-C_(3)N_(4)hybrids for efficient photocatalytic water splitting.展开更多
The development of low-cost and high-active cocatalysts is one of the most significant links for photocatalytic water splitting.Herein,a novel strategy of electron delocalization modulation for transition metal sulfid...The development of low-cost and high-active cocatalysts is one of the most significant links for photocatalytic water splitting.Herein,a novel strategy of electron delocalization modulation for transition metal sulfides has been developed by anion hybridization.P-modified CoS_(2)(CoS_(2)|P)nanocrystals were firstly fabricated via a gas-solid reaction and coupled with CdS nanorods to construct a composite catalyst for solar H2 evolution reaction(HER).The CdS/CoS_(2)|P catalyst shows an HER rate of 57.8 pmol h-1,which is 18 times that of the bare CdS,8 times that of the CdS/CoS2,and twice that of Pt/CdS.The reduced energy barrier and suppressed reverse reaction for HER on the catalyst have been predicted and explained by density functional theory(DFT)calculation.The underlying design strategy of novel cocatalysts by electron delocalization modulation may shed light on the rational development of other advanced catalysts for energy conversion.展开更多
基金financially supported by National Natural Science Foundation of China(Nos.22002060 and 51872138)Natural Science Foundation of Jiangsu Province(No.BK20181380)+3 种基金Qing Lan Project,Six Talent Peaks Project in Jiangsu Province(No.XCL029)Priority Academic Program Development of the Jiangsu Higher Education Institutions(PAPD)support provided by China Scholarships Council(CSC No.202008320109)China Postdoctoral Science Foundation(No.2020M681564)。
文摘Development of low-cost and efficient photocatalytic materials with visible-light response is of urgent need for solving energy and environmental problems.Here,a metal-free two-dimensional(2D)π-conjugated hybrid g-C_(3)N_(4)photocatalyst with tunable band structure was prepared by a novel one-pot bottom-up method based on a supersaturated precipitation process of urea and triethanolamine(TEOA)solution.The microstructure of the hybrid g-C_(3)N_(4)is revealed to be a compound of periodic tri-s-triazine units grafted with N-doped graphene(GR)fragments.From experimental evidence and theoretical calculations,the two differentπ-conjugated fragments in the hybrid g-C_(3)N_(4)material are proved to construct a 2D in-plane junction structure,thereby expanding the light absorption range and accelerating the interface charge transfer.Theπ-conjugated electron coupling in the 2D photocatalyst eliminates the grain boundary effect,and the coupled highest occupied molecular orbital(HOMO)effectively promotes the separation of photo-induced charge carriers.Compared with the g-C_(3)N_(4)prepared by the conventional method,the visible-light H2 production activity of the optimized sample is enhanced by 253%.This work provides a new strategy of constructing metal-free g-C_(3)N_(4)hybrids for efficient photocatalytic water splitting.
基金supported by the National Natural Science Foundation of China(Nos.51872138 and 22002060)Natural Science Foundation of Jiangsu Province(No.BK20181380)+2 种基金Qing Lan Project,Six Talent Peaks Project in Jiangsu Province(No.XCL-029)Priority Academic Program Development of the Jiangsu Higher Education Institutions(PAPD).Dr.Hengming Huang gratefully acknowledges the support provided by China Scholarships Council(CSC No.202008320109)China Postdoctoral Science Foundation(No.2020M681564).
文摘The development of low-cost and high-active cocatalysts is one of the most significant links for photocatalytic water splitting.Herein,a novel strategy of electron delocalization modulation for transition metal sulfides has been developed by anion hybridization.P-modified CoS_(2)(CoS_(2)|P)nanocrystals were firstly fabricated via a gas-solid reaction and coupled with CdS nanorods to construct a composite catalyst for solar H2 evolution reaction(HER).The CdS/CoS_(2)|P catalyst shows an HER rate of 57.8 pmol h-1,which is 18 times that of the bare CdS,8 times that of the CdS/CoS2,and twice that of Pt/CdS.The reduced energy barrier and suppressed reverse reaction for HER on the catalyst have been predicted and explained by density functional theory(DFT)calculation.The underlying design strategy of novel cocatalysts by electron delocalization modulation may shed light on the rational development of other advanced catalysts for energy conversion.
