Atomically dispersed Mo atoms on amorphous g-C3N4 promotes visible-light absorption and charge carriers transfer

Abstract Atomically dispersed atom catalysts with atomically distributed active metal centers have attracted great attention owing to the maximum atom efficiency and excellent selectivity. Herein, for the first time, we found atomically dispersed Mo atoms can be formed on g-C3N4, and induce its amorphous transformation. This amorphous transformation leads to the formation of strong band tails with remarkably enhancing the absorbance edge of Mo-C3N4 up to 750 nm, resulting in almost whole visible-light range absorption. The formation of new Mo-C and Mo-N bonds due to strong interfacial interaction between atomically dispersed Mo atoms and g-C3N4 provide new electron and hole transport pathways to accelerate the separation of charge carriers. As a result, amorphous Mo/C3N4 (a-Mo/C3N4) reveals excellent photoreduction of CO2, yielding CO and H2 productions of 18 and 37 μmol g−1 h−1 under visible-light illumination (λ > 420 nm), which manifest a remarkable 10.6- and 4-folds enhancement of that over crystalline g-C3N4. This finding provides a conceptually different approach to fabricate high-efficient photocatalyst through the strong interfacial interaction between atomically dispersed metal atoms and host.

[1]  Danielle M. Schultz,et al.  Solar Synthesis: Prospects in Visible Light Photocatalysis , 2014, Science.

[2]  Xiaobo Chen,et al.  Increasing Solar Absorption for Photocatalysis with Black Hydrogenated Titanium Dioxide Nanocrystals , 2011, Science.

[3]  Y. Horiuchi,et al.  Understanding TiO2 photocatalysis: mechanisms and materials. , 2014, Chemical reviews.

[4]  Rui Shi,et al.  Enhancement of photocurrent and photocatalytic activity of ZnO hybridized with graphite-like C3N4 , 2011 .

[5]  J. Yates,et al.  Photocatalysis on TiO2 Surfaces: Principles, Mechanisms, and Selected Results , 1995 .

[6]  Jiaguo Yu,et al.  Single‐Atom Engineering of Directional Charge Transfer Channels and Active Sites for Photocatalytic Hydrogen Evolution , 2018, Advanced Functional Materials.

[7]  F. Wang,et al.  Mechanistic insights into CO2 reduction on Cu/Mo-loaded two-dimensional g-C3N4(001). , 2017, Physical chemistry chemical physics : PCCP.

[8]  R. Si,et al.  Supported Rhodium Catalysts for Ammonia-Borane Hydrolysis: Dependence of the Catalytic Activity on the Highest Occupied State of the Single Rhodium Atoms. , 2017, Angewandte Chemie.

[9]  Yajun Wang,et al.  Facile in situ synthesis of graphitic carbon nitride (g-C3N4)-N-TiO2 heterojunction as an efficient photocatalyst for the selective photoreduction of CO2 to CO , 2014 .

[10]  Jin Zhao,et al.  Octahedral Pd@Pt1.8Ni core-shell nanocrystals with ultrathin PtNi alloy shells as active catalysts for oxygen reduction reaction. , 2015, Journal of the American Chemical Society.

[11]  Yi‐Jun Xu,et al.  Constructing one-dimensional silver nanowire-doped reduced graphene oxide integrated with CdS nanowire network hybrid structures toward artificial photosynthesis. , 2015, Nanoscale.

[12]  Ying Dai,et al.  Composite of CH3NH3PbI3 with Reduced Graphene Oxide as a Highly Efficient and Stable Visible‐Light Photocatalyst for Hydrogen Evolution in Aqueous HI Solution , 2018, Advanced materials.

[13]  W. Ho,et al.  In situ construction of g-C3N4/g-C3N4 metal-free heterojunction for enhanced visible-light photocatalysis. , 2013, ACS applied materials & interfaces.

[14]  J. Grunwaldt,et al.  Facile synthesis of surface N-doped Bi2O2CO3: Origin of visible light photocatalytic activity and in situ DRIFTS studies. , 2016, Journal of hazardous materials.

[15]  Matthew R. Shaner,et al.  Amorphous TiO2 coatings stabilize Si, GaAs, and GaP photoanodes for efficient water oxidation , 2014, Science.

[16]  P. Kamat,et al.  Environmentally benign photocatalysts : applications of titanium oxide-based materials , 2010 .

[17]  H. Yoshida,et al.  Photocatalytic reduction of CO2 with water promoted by Ag clusters in Ag/Ga2O3 photocatalysts , 2015 .

[18]  Junfa Zhu,et al.  Synergetic interaction between neighbouring platinum monomers in CO2 hydrogenation , 2018, Nature Nanotechnology.

[19]  Yoshiki Shimizu,et al.  Hexagonal-close-packed, hierarchical amorphous TiO2 nanocolumn arrays: transferability, enhanced photocatalytic activity, and superamphiphilicity without UV irradiation. , 2008, Journal of the American Chemical Society.

[20]  Wenbin Lin,et al.  Metal-organic frameworks for artificial photosynthesis and photocatalysis. , 2014, Chemical Society reviews.

[21]  H. Yang,et al.  Nickel nanoparticles coated with graphene layers as efficient co-catalyst for photocatalytic hydrogen evolution , 2017 .

[22]  Hui‐Ming Cheng,et al.  An Amorphous Carbon Nitride Photocatalyst with Greatly Extended Visible‐Light‐Responsive Range for Photocatalytic Hydrogen Generation , 2015, Advanced materials.

[23]  A. Fujishima,et al.  Electrochemical Photolysis of Water at a Semiconductor Electrode , 1972, Nature.

[24]  Heliang Yao,et al.  Core-shell LaPO4/g-C3N4 nanowires for highly active and selective CO2 reduction , 2017 .

[25]  Xiao Hua Yang,et al.  Accelerating Neutral Hydrogen Evolution with Tungsten Modulated Amorphous Metal Hydroxides , 2018 .

[26]  M. Antonietti,et al.  A metal-free polymeric photocatalyst for hydrogen production from water under visible light. , 2009, Nature materials.

[27]  B. Ohtani,et al.  Photocatalytic Activity of Amorphous−Anatase Mixture of Titanium(IV) Oxide Particles Suspended in Aqueous Solutions , 1997 .

[28]  Xiufang Chen,et al.  Highly selective hydrogenation of furfural to furfuryl alcohol over Pt nanoparticles supported on g-C3N4 nanosheets catalysts in water , 2016, Scientific Reports.

[29]  Gang Chen,et al.  Facile approach to synthesize g-PAN/g-C3N4 composites with enhanced photocatalytic H2 evolution activity. , 2014, ACS applied materials & interfaces.

[30]  Jianlin Shi,et al.  Highly selective CO2 photoreduction to CO over g-C3N4/Bi2WO6 composites under visible light , 2015 .

[31]  Siang-Piao Chai,et al.  Graphitic Carbon Nitride (g-C3N4)-Based Photocatalysts for Artificial Photosynthesis and Environmental Remediation: Are We a Step Closer To Achieving Sustainability? , 2016, Chemical reviews.

[32]  F. Dong,et al.  Efficient C3N4/graphene oxide macroscopic aerogel visible-light photocatalyst , 2016 .

[33]  M. Beller,et al.  Bridging homogeneous and heterogeneous catalysis by heterogeneous single-metal-site catalysts , 2018, Nature Catalysis.

[34]  Thomas A. Kennedy,et al.  Doping semiconductor nanocrystals , 2005, Nature.

[35]  F. Dong,et al.  Multifunctional g-C 3 N 4 /graphene oxide wrapped sponge monoliths as highly efficient adsorbent and photocatalyst , 2018, Applied Catalysis B: Environmental.

[36]  X. Wen,et al.  Unravelling charge carrier dynamics in protonated g-C3N4 interfaced with carbon nanodots as co-catalysts toward enhanced photocatalytic CO2 reduction: A combined experimental and first-principles DFT study , 2017, Nano Research.

[37]  Abdul Rahman Mohamed,et al.  Surface charge modification via protonation of graphitic carbon nitride (g-C3N4) for electrostatic self-assembly construction of 2D/2D reduced graphene oxide (rGO)/g-C3N4 nanostructures toward enhanced photocatalytic reduction of carbon dioxide to methane , 2015 .

[38]  Mietek Jaroniec,et al.  Polymeric Photocatalysts Based on Graphitic Carbon Nitride , 2015, Advanced materials.

[39]  Tao Zhang,et al.  Atomically dispersed Ni(i) as the active site for electrochemical CO2 reduction , 2018 .

[40]  Tak W. Kee,et al.  A Benchmark Quantum Yield for Water Photoreduction on Amorphous Carbon Nitride , 2017 .

[41]  T. Kajino,et al.  Calcium titanate photocatalyst prepared by a flux method for reduction of carbon dioxide with water , 2015 .

[42]  A. Dazzi,et al.  Conducting polymer nanostructures for photocatalysis under visible light. , 2015, Nature materials.

[43]  Xiaofeng Yang,et al.  Single-atom catalysis of CO oxidation using Pt1/FeOx. , 2011, Nature chemistry.

[44]  H. Yang,et al.  Orange Zinc Germanate with Metallic Ge-Ge Bonds as a Chromophore-Like Center for Visible-Light-Driven Water Splitting. , 2015, Angewandte Chemie.

[45]  R. Asahi,et al.  Visible-Light Photocatalysis in Nitrogen-Doped Titanium Oxides , 2001, Science.

[46]  C. S. Lim,et al.  Simultaneous phase and size control of upconversion nanocrystals through lanthanide doping , 2010, Nature.

[47]  M. Jaroniec,et al.  Graphene-based semiconductor photocatalysts. , 2012, Chemical Society Reviews.

[48]  L. Yuliati,et al.  Photocatalytic conversion of methane. , 2008, Chemical Society reviews.