Defect-rich fluorographene nanosheets for artificial N2 fixation under ambient conditions.

NH3, synthesized by the Haber-Bosch process, is essential for fertilisers in order to feed the world's growing population, however, it causes massive energy consumption and generates large amounts of greenhouse gases. Electrochemical N2 reduction reaction (NRR) at ambient conditions is highly desirable for energy-efficient and sustainable NH3 production but this requires an efficient catalyst. In this work, we report a defect-rich fluorographene nanosheet synthesised via fluorination of graphene for NRR electrocatalysis. Such an electrocatalyst shows an NH3 formation rate of 9.3 μg h-1 mgcat.-1 and a faradaic efficiency of 4.2% at -0.7 V vs. reversible hydrogen electrode in 0.1 M Na2SO4. Density functional theory calculations reveal that the fluorination of graphene induces defects, which not only provide reaction sites for NRR but effectively activate N2 molecules.

[1]  Dan Wu,et al.  High-performance N2-to-NH3 fixation by a metal-free electrocatalyst. , 2019, Nanoscale.

[2]  Nan Zhang,et al.  Promoting nitrogen electroreduction to ammonia with bismuth nanocrystals and potassium cations in water , 2019, Nature Catalysis.

[3]  Abdullah M. Asiri,et al.  High-Performance N2-to-NH3 Conversion Electrocatalyzed by Mo2C Nanorod , 2018, ACS central science.

[4]  W. Fang,et al.  Ti3C2Tx (T = F, OH) MXene nanosheets: conductive 2D catalysts for ambient electrohydrogenation of N2 to NH3 , 2018 .

[5]  Abdullah M. Asiri,et al.  Ambient NH3 synthesis via electrochemical reduction of N2 over cubic sub-micron SnO2 particles. , 2018, Chemical communications.

[6]  Fengli Qu,et al.  Cr2O3 nanofiber: a high-performance electrocatalyst toward artificial N2 fixation to NH3 under ambient conditions. , 2018, Chemical communications.

[7]  B. Tang,et al.  Electrocatalytic Hydrogenation of N2 to NH3 by MnO: Experimental and Theoretical Investigations , 2018, Advanced science.

[8]  Abdullah M. Asiri,et al.  Ag nanosheets for efficient electrocatalytic N2 fixation to NH3 under ambient conditions. , 2018, Chemical communications.

[9]  Abdullah M. Asiri,et al.  Efficient and durable N2 reduction electrocatalysis under ambient conditions: β-FeOOH nanorods as a non-noble-metal catalyst. , 2018, Chemical communications.

[10]  Faxing Wang,et al.  Ambient N2 fixation to NH3 at ambient conditions: Using Nb2O5 nanofiber as a high-performance electrocatalyst , 2018, Nano Energy.

[11]  Abdullah M. Asiri,et al.  Boosted Electrocatalytic N2 Reduction to NH3 by Defect‐Rich MoS2 Nanoflower , 2018, Advanced Energy Materials.

[12]  Abdullah M. Asiri,et al.  TiO2 nanoparticles–reduced graphene oxide hybrid: an efficient and durable electrocatalyst toward artificial N2 fixation to NH3 under ambient conditions , 2018 .

[13]  B. Tang,et al.  High-performance artificial nitrogen fixation at ambient conditions using a metal-free electrocatalyst , 2018, Nature Communications.

[14]  Baozhan Zheng,et al.  Enabling Effective Electrocatalytic N2 Conversion to NH3 by the TiO2 Nanosheets Array under Ambient Conditions. , 2018, ACS applied materials & interfaces.

[15]  Tingshuai Li,et al.  High-Performance Electrohydrogenation of N2 to NH3 Catalyzed by Multishelled Hollow Cr2O3 Microspheres under Ambient Conditions , 2018, ACS Catalysis.

[16]  Qiang Zhang,et al.  A Review of Electrocatalytic Reduction of Dinitrogen to Ammonia under Ambient Conditions , 2018 .

[17]  Xuping Sun,et al.  Electrochemical N2 fixation to NH3 under ambient conditions: Mo2N nanorod as a highly efficient and selective catalyst. , 2018, Chemical communications.

[18]  Bo Tang,et al.  Electrochemical Ammonia Synthesis via Nitrogen Reduction Reaction on a MoS2 Catalyst: Theoretical and Experimental Studies , 2018, Advanced materials.

[19]  Yu Ding,et al.  An Amorphous Noble-Metal-Free Electrocatalyst that Enables Nitrogen Fixation under Ambient Conditions. , 2018, Angewandte Chemie.

[20]  H. Xin,et al.  Ambient ammonia synthesis via palladium-catalyzed electrohydrogenation of dinitrogen at low overpotential , 2018, Nature Communications.

[21]  Shi-Zhang Qiao,et al.  Rational design of electrocatalysts and photo(electro)catalysts for nitrogen reduction to ammonia (NH3) under ambient conditions , 2018 .

[22]  Zhijiang Wang,et al.  Electrochemical reduction of aqueous nitrogen (N2) at a low overpotential on (110)-oriented Mo nanofilm , 2017 .

[23]  M. Symes,et al.  Recent progress towards the electrosynthesis of ammonia from sustainable resources , 2017 .

[24]  Jun-min Yan,et al.  Au Sub‐Nanoclusters on TiO2 toward Highly Efficient and Selective Electrocatalyst for N2 Conversion to NH3 at Ambient Conditions , 2017, Advanced materials.

[25]  Claudio Ampelli,et al.  Electrocatalytic Synthesis of Ammonia at Room Temperature and Atmospheric Pressure from Water and Nitrogen on a Carbon-Nanotube-Based Electrocatalyst. , 2017, Angewandte Chemie.

[26]  Aicheng Chen,et al.  Facile one-pot synthesis of fluorinated graphene oxide for electrochemical sensing of heavy metal ions , 2017 .

[27]  Thomas F. Jaramillo,et al.  Electrochemical Ammonia Synthesis-The Selectivity Challenge , 2017 .

[28]  Joseph H. Montoya,et al.  The Challenge of Electrochemical Ammonia Synthesis: A New Perspective on the Role of Nitrogen Scaling Relations. , 2015, ChemSusChem.

[29]  Xiaobo Ji,et al.  Acid induced fluorinated graphene oxide , 2015 .

[30]  F. Kang,et al.  Graphene derivatives: graphane, fluorographene, graphene oxide, graphyne and graphdiyne , 2014 .

[31]  Tapas Kuila,et al.  Simultaneous reduction, exfoliation, and nitrogen doping of graphene oxide via a hydrothermal reaction for energy storage electrode materials , 2014 .

[32]  Robert Schlögl,et al.  The Haber-Bosch process revisited: on the real structure and stability of "ammonia iron" under working conditions. , 2013, Angewandte Chemie.

[33]  S. Badwal,et al.  Review of Electrochemical Ammonia Production Technologies and Materials , 2013 .

[34]  A. V. van Duin,et al.  Graphene to fluorographene and fluorographane: a theoretical study , 2013, Nanotechnology.

[35]  Jinqing Wang,et al.  Synthesis of fluorinated graphene with tunable degree of fluorination , 2012 .

[36]  M. Otyepka,et al.  Functionalization of graphene: covalent and non-covalent approaches, derivatives and applications. , 2012, Chemical reviews.

[37]  Xiao-Qian Wang,et al.  Structural and electronic properties of fluorographene. , 2011, Small.

[38]  Lei Fu,et al.  Synthesis of Nitrogen‐Doped Graphene Using Embedded Carbon and Nitrogen Sources , 2011, Advanced materials.

[39]  Anthony V. Cugini,et al.  CO2 attraction by specifically adsorbed anions and subsequent accelerated electrochemical reduction , 2010 .

[40]  R. Ruoff,et al.  Graphene and Graphene Oxide: Synthesis, Properties, and Applications , 2010, Advanced materials.

[41]  M. Koper,et al.  Nitrogen cycle electrocatalysis. , 2009, Chemical reviews.

[42]  Hui‐Ming Cheng,et al.  Synthesis of graphene sheets with high electrical conductivity and good thermal stability by hydrogen arc discharge exfoliation. , 2009, ACS nano.

[43]  W. Winiwarter,et al.  How a century of ammonia synthesis changed the world , 2008 .

[44]  J. Nørskov,et al.  Ammonia for hydrogen storage: challenges and opportunities , 2008 .

[45]  Claus H. Christensen,et al.  Towards an ammonia-mediated hydrogen economy? , 2006 .

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

[47]  R. Yazami,et al.  Synthesis and Characterization of Highly Fluorinated Graphite Containing sp2 and sp3 Carbon , 2004 .

[48]  Robert Schlögl,et al.  Catalytic synthesis of ammonia-a "never-ending story"? , 2003, Angewandte Chemie.

[49]  G. Watt,et al.  Spectrophotometric Method for Determination of Hydrazine , 1952 .

[50]  Xin-bo Zhang,et al.  Electrochemical Reduction of N2 under Ambient Conditions for Artificial N2 Fixation and Renewable Energy Storage Using N2/NH3 Cycle , 2017, Advanced materials.