Supporting Information Cobalt Molybdenum Oxide Derived High-Performance Electrocatalyst for the Hydrogen Evolution Reaction Mingjie Zang, [a] Ning Xu, [a] Guoxuan Cao, [a] Zhengjun Chen, [a] Jie Cui, [b] Liyong Gan,* [a] Hongbin Dai, [a] Xianfeng Yang, [b] and Ping Wang* [a] a M. J. Zang, N. Xu, G. X. Cao, Z. J. Chen, Dr. L. Y. Gan, Prof. H. B. Dai, Prof. P. Wang School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, P. R. China b Dr. J. Cui, Prof. X. F. Yang Analytical and Testing Centre, South China University of Technology, Guangzhou 510641, P. R. China E-mail: ganly@scut.edu.cn (L.Y. Gan), mspwang@scut.edu.cn (P. Wang)
Figure S1. Representative TEM images of porous nanosheets. Figure S2. Raman spectrum of the Co/Co2Mo3O8/NF catalyst. Figure S3. LSV curves for Co-Mo-O-derived electrocatalyst collected in 1 M KOH at different temperature.
Figure S4. HER polarization curves with ir compensation. Figure S5. Electrochemical capacitance measurements for CoMoO4 nh2o/nf (a) and Co/Co2Mo3O8/NF (b). Cyclic voltammograms at different scan rates were taken in a potential range (0.15~0.25 V vs. RHE) without faradic processes. Figure S6. FE-SEM images of the Co/Co2Mo3O8/NF catalyst at initial state (a) and after 24 h stability test (b).
Figure S7. Models of Co2Mo3O8 with (a) a Co vacancy and (b) an interstitial O atom. The blue, gray, red, yellow and black balls represent Co, Mo and O atoms, Co vacancy and interstitial O atom, respectively. Figure S8. (a) Crystal structure of P63mc Co2Mo3O8. (b)-(e) Top (upper panel) and side view (lower panel) of the models of fcc Co (111), Co-, Mo-, and O-terminated Co2Mo3O8 (001) surfaces, respectively. The blue, gray and red balls represent Co, Mo and O, respectively.
Table S1. Comparison of The HER activities of the as-achieved Co/Co2Mo3O8/NF electrocatalyst and reported electrocatalysts. Electrocatalyst Overpotential (mv) ( @10 ma cm -2 ) Tafel slope (mv dec -1 ) Electrolyte Reference Co/Co2Mo3O8/NF 25 33 1 M KOH this work Ni/NiO/Cr2O3 30 1 M KOH [1] Co/Co3O4 90 44 1 M KOH mpf-co-mos2 26 74 1 M KOH NiMo/Ni(OH)2/NiAl 78 1 M KOH Co-NRCNTs 370 >69 1 M KOH Co(OH)2/PANI 90 91.6 1 M KOH Ru-Co nanoalloy 28 31 1 M KOH [2] [3] [4] [5] [6] [7] MoCX 142 53 1 M KOH 151 59 0.5M H2SO4 [8] Ni Mo nanopowers 80 2 M KOH CoNiFe alloy 78 100 1 M NaOH CoMoS/CoMoO4 80 58 0.5 M H2SO4 [9] [10] [11] MoP 150 54 0.5 M H2SO4 [12] MoO2/MoSe2 181 49.1 0.5 M H2SO4 [13]
Supporting References (1) Gong, M.; Zhou, W.; Kenney, M. J.; Kapusta, R.; Cowley, S.; Wu, Y. P.; Lu, B. G.; Lin, M.-C.; Wang, D.-Y.; Yang, J.; Hwang, B.-J.; Dai, H. J. Blending Cr 2O 3 into a NiO-Ni Electrocatalyst for Sustained Water Splitting. Angew. Chem. Int. Ed. 2015, 127, 12157 12161. (2) Yan, X. D.; Tian, L. H.; He, M.; Chen, X. B. Three-Dimensional Crystalline/Amorphous Co/Co 3O 4 Core/Shell Nanosheets as Efficient Electrocatalysts for the Hydrogen Evolution Reaction. Nano Lett. 2015, 15, 6015 6021. (3) Deng, J.; Li, H. B.; Wang, S. H.; Ding, D.; Chen, M. S.; Liu, C.; Tian, Z. Q.; Novoselov, K. S.; Ma, C.; Deng, D. H.; Bao, X. H. Multiscale Structural and Electronic Control of Molybdenum Disulfide Foam for Highly Efficient Hydrogen Production. Nat. Commun. 2017, 8, 14430 14435. (4) Niu, S.; Jiang, W.-J.; Tang, T.; Zhang, Y.; Li, J.-H.; Hu, J.-S. Facile and Scalable Synthesis of Robust Ni(OH) 2 Nanoplate Arrays on NiAl Foil as Hierarchical Active Scaffold for Highly Efficient Overall Water Splitting. Adv. Sci. 2017, 4, 1700084 1700088. (5) Zou, X. X.; Huang, X. X.; Goswami, A.; Silva, R.; Sathe, B. R.; Mikmeková, E.; Asefa, T. Cobalt-Embedded Nitrogen-Rich Carbon Nanotubes Efficiently Catalyze Hydrogen Evolution Reaction at All ph values. Angew. Chem. Int. Et. 2014, 126, 4461 4465. (6) Feng, J.-X.; Ding, L.-X.; Ye, S.-H.; He, X.-J.; Xu, H.; Tong Y.-X.; Li, G.-R. Co(OH) 2@PANI Hybrid Nanosheets with 3D Networks as High Performance Electrocatalysts for Hydrogen Evolution Reaction. Adv. Mater. 2015, 27, 7051 7057. (7) Su, J. W.; Yang, Y.; Xia, G. L.; Chen, J. T.; Jiang, P.; Chen Erratum, Q. W. Ruthenium-Cobalt Nanoalloys Encapsulated in Nitrogen-doped Graphene as Active Electrocatalysts for Producing Hydrogen in Alkaline Media. Nat. Commun. 2017, 8, 14969 14977. (8) Wu, H. B.; Xia, B.; Y.; Yu, L.; Yu, X.-Y.; Wen (David) Loua, X. Porous Molybdenum Carbide Nanooctahedrons Synthesized via Confined Carburization in Metal-Organic Frameworks for Efficient Hydrogen Production. Nat. Commun. 2015, 6, 6512 6519. (9) Mckone, J. R.; Sadtler, B. F.; Werlang, C. A.; Lewis, N. S.; Gray, H. B. Ni Mo Nanopowders for Efficient Electrochemical Hydrogen Evolution. ACS Catal. 2013, 3, 166 169. (10) Jafarian, M.; Azizi, O.; Gobal, F.; Mahjani, M. G. Kinetics and Electrocatalytic Behavior of Nanocrystalline CoNiFe Alloy in Hydrogen Evolution Reaction. Int. J. Hydrogen Energy 2007, 32, 1686 1693. (11) Liu, Y-R.; Shang, X.; Gao, W-K.; Dong, B.; Li, X.; Li, X.-H.; Zhao, J.-C.; Chai, Y.-M.; Liu, Y.-Q.; Liu, C.-G. In Situ Sulfurized CoMoS/CoMoO 4 Shell Core Nanorods Supported on N-doped Reduced Graphene Oxide (NRGO) as Efficient Electrocatalyst for Hydrogen Evolution Reaction. J. Mater. Chem. A 2017, 5, 2885 2896. (12) Xiao, P.; Sk, M. A.; Thia, L.; Ge, X. M.; Lim, R. J.; Wang, J.-Y.; Lim, K. H.; Wang, X. Molybdenum Phosphide as an Efficient Electrocatalyst for the Hydrogen Evolution Reaction. Energy Environ. Sci. 2014, 7, 2624 26291. (13) Chen, X.S.; Liu, G. B.; Zheng, W.; Feng, W.; Cao, W. W.; Hu, W. P.; Hu, P. A. Vertical 2D MoO 2/MoSe 2 Core Shell Nanosheet Arrays as High Performance Electrocatalysts for Hydrogen Evolution Reaction. Adv. Funct. Mater. 2016, 26, 8537 8544.