Noble metal-free reduced graphene oxide-ZnxCd₁-xS nanocomposite with enhanced solar photocatalytic H₂-production performance.

Design and preparation of efficient artificial photosynthetic systems for harvesting solar energy by production of hydrogen from water splitting is of great importance from both theoretical and practical viewpoints. ZnS-based solid solutions have been fully proved to be an efficient visible-light driven photocatalysts, however, the H(2)-production rate observed for these solid solutions is far from exciting and sometimes an expensive Pt cocatalyst is still needed in order to achieve higher quantum efficiency. Here, for the first time we report the high solar photocatalytic H(2)-production activity over the noble metal-free reduced graphene oxide (RGO)-Zn(x)Cd(1-x)S nanocomposite prepared by a facile coprecipitation-hydrothermal reduction strategy. The optimized RGO-Zn(0.8)Cd(0.2)S photocatalyst has a high H(2)-production rate of 1824 μmol h(-1) g(-1) at the RGO content of 0.25 wt % and the apparent quantum efficiency of 23.4% at 420 nm (the energy conversion efficiency is ca. 0.36% at simulated one-sun (AM 1.5G) illumination). The results exhibit significantly improved photocatalytic hydrogen production by 450% compared with that of the pristine Zn(0.8)Cd(0.2)S, and are better than that of the optimized Pt-Zn(0.8)Cd(0.2)S under the same reaction conditions, showing that the RGO-Zn(0.8)Cd(0.2)S nanocomposite represents one of the most highly active metal sulfide photocatalyts in the absence of noble metal cocatalysts. This work creates a green and simple way for using RGO as a support to enhance the photocatalytic H(2)-production activity of Zn(x)Cd(1-x)S, and also demonstrates that RGO is a promising substitute for noble metals in photocatalytic H(2)-production.

[1]  M. Jaroniec,et al.  Nitrogen self-doped nanosized TiO2 sheets with exposed {001} facets for enhanced visible-light photocatalytic activity. , 2011, Chemical communications.

[2]  Jiaguo Yu,et al.  Highly efficient visible-light-driven photocatalytic hydrogen production of CdS-cluster-decorated graphene nanosheets. , 2011, Journal of the American Chemical Society.

[3]  A. Xu,et al.  Highly Durable N-Doped Graphene/CdS Nanocomposites with Enhanced Photocatalytic Hydrogen Evolution from Water under Visible Light Irradiation , 2011 .

[4]  Kian Ping Loh,et al.  Hydrothermal Dehydration for the “Green” Reduction of Exfoliated Graphene Oxide to Graphene and Demonstration of Tunable Optical Limiting Properties , 2009 .

[5]  Liejin Guo,et al.  Photocatalytic H2 evolution under visible light irradiation on a novel CdxCuyZn1−x−yS catalyst , 2008 .

[6]  Jiaguo Yu,et al.  Dye-sensitized solar cells based on anatase TiO 2 hollow spheres/carbon nanotube composite films , 2011 .

[7]  M. Jaroniec,et al.  Ni(OH)2 modified CdS nanorods for highly efficient visible-light-driven photocatalytic H2 generation , 2011 .

[8]  S. Ikeda,et al.  Multicomponent sulfides as narrow gap hydrogen evolution photocatalysts. , 2010, Physical chemistry chemical physics : PCCP.

[9]  K. Domen,et al.  Facile Cd−Thiourea Complex Thermolysis Synthesis of Phase-Controlled CdS Nanocrystals for Photocatalytic Hydrogen Production under Visible Light , 2007 .

[10]  Ling Zhang,et al.  Enhanced photocatalytic hydrogen evolution under visible light over Cd1−xZnxS solid solution with cubic zinc blend phase , 2010 .

[11]  R. Kaner,et al.  Honeycomb carbon: a review of graphene. , 2010, Chemical reviews.

[12]  Yuanming Zhang,et al.  Synthesis of nano titania particles embedded in mesoporous SBA-15: characterization and photocatalytic activity. , 2006, Journal of hazardous materials.

[13]  Saeed M. Al-Zahrani,et al.  A framework for visible-light water splitting , 2010 .

[14]  Yongfa Zhu,et al.  Significant enhancement of the visible photocatalytic degradation performances of γ-Bi2MoO6 nanoplate by graphene hybridization , 2011 .

[15]  Ankun Zhou,et al.  Hierarchical ZnS‐In2S3‐CuS Nanospheres with Nanoporous Structure: Facile Synthesis, Growth Mechanism, and Excellent Photocatalytic Activity , 2010 .

[16]  Jiaguo Yu,et al.  Visible-light-induced photoelectrochemical behaviors of Fe-modified TiO2 nanotube arrays. , 2011, Nanoscale.

[17]  Jean François Dr. Reber,et al.  Photochemical production of hydrogen with zinc sulfide suspensions , 1984 .

[18]  Yuehe Lin,et al.  Graphene/TiO2 nanocomposites: synthesis, characterization and application in hydrogen evolution from water photocatalytic splitting , 2010 .

[19]  Xiaoling Yang,et al.  Preparation of graphene–TiO2 composites with enhanced photocatalytic activity , 2011 .

[20]  Jiaguo Yu,et al.  Hydrothermal Preparation and Photocatalytic Activity of Hierarchically Sponge-like Macro-/Mesoporous Titania , 2007 .

[21]  Liejin Guo,et al.  Enhanced Photocatalytic Hydrogen Evolution over Cu-Doped ZnIn2S4 under Visible Light Irradiation , 2008 .

[22]  Jiaguo Yu,et al.  Fabrication and Characterization of Visible-Light-Driven Plasmonic Photocatalyst Ag/AgCl/TiO2 Nanotube Arrays , 2009 .

[23]  Hideki Kato,et al.  Photocatalytic H2 evolution reaction from aqueous solutions over band structure-controlled (AgIn)xZn2(1-x)S2 solid solution photocatalysts with visible-light response and their surface nanostructures. , 2004, Journal of the American Chemical Society.

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

[25]  A. Kudo,et al.  Photocatalytic Hydrogen Evolution on ZnS−CuInS2−AgInS2 Solid Solution Photocatalysts with Wide Visible Light Absorption Bands , 2006 .

[26]  G. Eda,et al.  Large-area ultrathin films of reduced graphene oxide as a transparent and flexible electronic material. , 2008, Nature nanotechnology.

[27]  P. Kubelka,et al.  New Contributions to the Optics of Intensely Light-Scattering Materials. Part I , 1948 .

[28]  M. Jaroniec,et al.  Preparation and Enhanced Visible-Light Photocatalytic H2-Production Activity of Graphene/C3N4 Composites , 2011 .

[29]  Andre K. Geim,et al.  Electric Field Effect in Atomically Thin Carbon Films , 2004, Science.

[30]  K. Müllen,et al.  Transparent, conductive graphene electrodes for dye-sensitized solar cells. , 2008, Nano letters.

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

[32]  Jiaguo Yu,et al.  Facile preparation and enhanced photocatalytic H2-production activity of Cu(OH)2 cluster modified TiO2 , 2011 .

[33]  A. Kudo,et al.  Heterogeneous photocatalyst materials for water splitting. , 2009, Chemical Society reviews.

[34]  A. Deshpande,et al.  Interfacial and physico-chemical properties of polymer-supported CdSZnS nanocomposites and their role in the visible-light mediated photocatalytic splitting of water. , 2009, Journal of colloid and interface science.

[35]  M. Jaroniec,et al.  Preparation and enhanced visible-light photocatalytic H2-production activity of CdS-sensitized Pt/TiO2 nanosheets with exposed (001) facets. , 2011, Physical chemistry chemical physics : PCCP.

[36]  D. Kuang,et al.  A mild one-step process from graphene oxide and Cd2+ to a graphene-CdSe quantum dot nanocomposite with enhanced photoelectric properties. , 2012, Chemphyschem : a European journal of chemical physics and physical chemistry.

[37]  Jiaguo Yu,et al.  Visible light photocatalytic H₂-production activity of CuS/ZnS porous nanosheets based on photoinduced interfacial charge transfer. , 2011, Nano letters.

[38]  A. Hagfeldt,et al.  Photoelectrochemical studies of colloidal TiO2 films: The effect of oxygen studied by photocurrent transients , 1995 .

[39]  Rose Amal,et al.  Reducing Graphene Oxide on a Visible-Light BiVO4 Photocatalyst for an Enhanced Photoelectrochemical Water Splitting , 2010 .

[40]  Jun Zhang,et al.  Preparation and enhanced visible-light photocatalytic H2-production activity of CdS quantum dots-sensitized Zn1−xCdxS solid solution , 2010 .

[41]  Haixin Chang,et al.  Hydrogen evolution from water using semiconductor nanoparticle/graphene composite photocatalysts without noble metals , 2012 .

[42]  Jiaguo Yu,et al.  Preparation and enhanced daylight-induced photocatalytic activity of C,N,S-tridoped titanium dioxide powders. , 2008, Journal of hazardous materials.

[43]  M. Wills,et al.  Hydrogen generation from formic acid and alcohols using homogeneous catalysts. , 2010, Chemical Society reviews.

[44]  Prashant V Kamat,et al.  Anchoring semiconductor and metal nanoparticles on a two-dimensional catalyst mat. Storing and shuttling electrons with reduced graphene oxide. , 2010, Nano letters.

[45]  Lianzhou Wang,et al.  Nitrogen doped Sr₂Ta₂O₇ coupled with graphene sheets as photocatalysts for increased photocatalytic hydrogen production. , 2011, ACS nano.

[46]  K. Sing.  Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity (Recommendations 1984) , 1985 .

[47]  M. Jaroniec,et al.  A simple cation exchange approach to Bi-doped ZnS hollow spheres with enhanced UV and visible-light photocatalytic H2-production activity , 2011 .

[48]  A. Jana,et al.  Enhanced photoelectrochemical activity of electro-synthesized CdS–Bi2S3 composite films grown with self-designed cross-linked structure , 2010 .

[49]  Yongfa Zhu,et al.  Significantly enhanced photocatalytic performance of ZnO via graphene hybridization and the mechanism study , 2011 .

[50]  A. J. Frank,et al.  Visible-light-induced water cleavage and stabilization of n-type cadmium sulfide to photocorrosion with surface-attached polypyrrole-catalyst coating , 1982 .

[51]  T. Peng,et al.  One-pot synthesis of reduced graphene oxide-cadmium sulfide nanocomposite and its photocatalytic hydrogen production. , 2011, Physical chemistry chemical physics : PCCP.

[52]  Yang Hai,et al.  Enhanced Photocatalytic H2-Production Activity of TiO2 by Ni(OH)2 Cluster Modification , 2011 .