Stable and efficient seawater splitting on a porous phosphate-intercalated NiFe (oxy)hydroxide@NiMoO₄ core-shell micropillar electrode

Abstract

Seawater splitting powered by solar or wind sources is a significant renewable energy storage technology for the production of green hydrogen energy. However, both the chlorine evolution reaction and chloride corrosion are intractable issues in seawater splitting. Here, a porous electrode based on a phosphate-intercalated NiFe (oxy)hydroxide shell coated on a nickel molybdate (NiMoO₄) micropillar core (denoted as P-NiFe@NiMoO₄) is synthesized through an electrochemical oxidation strategy. During the electrochemical oxidation process, the etching of MoO₂ promotes the reconstruction of NiFe (oxy)hydroxide and the formation of porous structures in an alkaline solution. The optimized P-NiFe@NiMoO₄ electrocatalysts afford a low overpotential of 258 mV at a current density of 100 mA/cm² in alkaline seawater. By pairing the anode with a cathode of as-synthesized P-NiMoO, the electrolyzer presents a low voltage of 1.63 V at 100 mA/cm² in alkaline seawater with excellent stability. Moreover, the remarkable stability of the anode seems to be attributed to the in-situ phosphate formed during the electrochemical oxidation process to passivate chloride corrosion.

Keywords

NiFe (oxy)hydroxide / NiMoO₄ micropillars / oxygen evolution reaction / seawater splitting

References

[1] Cox CR,Nocera DG.Ten-percent solar-to-fuel conversion with nonprecious materials.Proc Natl Acad Sci U S A2014;111:14057-61 PMCID:PMC4191778

[2] Faber MS.Earth-abundant inorganic electrocatalysts and their nanostructures for energy conversion applications.Energy Environ Sci2014;7:3519-42

[3] Wang X,Wang X.Green synthesis of a highly efficient and stable single-atom iron catalyst anchored on nitrogen-doped carbon nanorods for the oxygen reduction reaction.ACS Sustainable Chem Eng2021;9:137-46

[4] Tiwari JN,Myung CW.Multicomponent electrocatalyst with ultralow Pt loading and high hydrogen evolution activity.Nat Energy2018;3:773-82

[5] Turner JA.Sustainable hydrogen production.Science2004;305:972-4

[6] Cabán-Acevedo M,Schmidt JR.Efficient hydrogen evolution catalysis using ternary pyrite-type cobalt phosphosulphide.Nat Mater2015;14:1245-51

[7] Luo J,Mayer MT.Water photolysis at 12.3% efficiency via perovskite photovoltaics and Earth-abundant catalysts.Science2014;345:1593-6

[8] Pu Z,Amiinu IS.A universal synthesis strategy for P-rich noble metal diphosphide-based electrocatalysts for the hydrogen evolution reaction.Energy Environ Sci2019;12:952-7

[9] Zhang J,Feng X.Support and interface effects in water-splitting electrocatalysts.Adv Mater2019;31:e1808167

[10] Seh ZW,Dickens CF,Nørskov JK.Combining theory and experiment in electrocatalysis: insights into materials design.Science2017;355:eaad4998

[11] Du J,Wang X,Liang HP.Electrochemical synthesis of cation vacancy-enriched ultrathin bimetallic oxyhydroxide nanoplatelets for enhanced water oxidation.ACS Appl Mater Interfaces2019;11:25958-66

[12] Li W,Yang H.A bio-inspired coordination polymer as outstanding water oxidation catalyst via second coordination sphere engineering.Nat Commun2019;10:5074 PMCID:PMC6838099

[13] Shi Q,Du D.Robust noble metal-based electrocatalysts for oxygen evolution reaction.Chem Soc Rev2019;48:3181-92

[14] Yu L,Sun J.Amorphous NiFe layered double hydroxide nanosheets decorated on 3D nickel phosphide nanoarrays: a hierarchical core-shell electrocatalyst for efficient oxygen evolution.J Mater Chem A2018;6:13619-23

[15] Yu L,Song S.Non-noble metal-nitride based electrocatalysts for high-performance alkaline seawater electrolysis.Nat Commun2019;10:5106 PMCID:PMC6841982

[16] Tong W,Dionigi F.Electrolysis of low-grade and saline surface water.Nat Energy2020;5:367-77

[17] Kuang Y,Meng Y.Solar-driven, highly sustained splitting of seawater into hydrogen and oxygen fuels.Proc Natl Acad Sci U S A2019;116:6624-9 PMCID:PMC6452679

[18] Lv F,Yang W.Ir-based alloy nanoflowers with optimized hydrogen binding energy as bifunctional electrocatalysts for overall water splitting.Small Methods2020;4:1900129

[19] Dong J,Wu Q.Facile preparation of Pt/CdS photocatalyst by a modified photoreduction method with efficient hydrogen production.Int J Hydrogen Energy2018;43:2139-47

[20] Liu S.The role of interface charge transfer on Pt based catalysts for water splitting.Int J Hydrogen Energy2018;43:15225-33

[21] Badiei YM,Renderos G.Rapid identification of homogeneous O₂ evolution catalysts and comparative studies of Ru(II)-carboxamides vs. Ru(II)-carboxylates in water-oxidation.J Catal2019;369:10-20

[22] Duan Y,Hu S.Scaled-up synthesis of amorphous NiFeMo oxides and their rapid surface reconstruction for superior oxygen evolution catalysis.Angew Chem2019;131:15919-24

[23] Wu T,Song J.Iron-facilitated dynamic active-site generation on spinel CoAl₂O₄ with self-termination of surface reconstruction for water oxidation.Nat Catal2019;2:763-72

[24] Du J,Wang X,Liang H.Cobalt oxyhydroxide with highly porous structures as active and stable phase for efficient water oxidation.Electrochimica Acta2019;303:231-8

[25] Chen G,Wang X,Wang Z.Iron-induced 3D nanoporous iron-cobalt oxyhydroxide on carbon cloth as a highly efficient electrode for oxygen evolution reaction.Chinese J Catal2019;40:1540-7

[26] Huang Z,Du Y.Chemical and structural origin of lattice oxygen oxidation in Co-Zn oxyhydroxide oxygen evolution electrocatalysts.Nat Energy2019;4:329-38

[27] Lv Q,Tan X,Cao L.Featherlike NiCoP holey nanoarrys for efficient and stable seawater splitting.ACS Appl Energy Mater2019;2:3910-7

[28] Wang S,Sun X.Synthesis of 3D heterostructure Co-doped Fe₂P electrocatalyst for overall seawater electrolysis.Applied Catalysis B: Environmental2021;297:120386

[29] Wu L,Zhang F.Heterogeneous bimetallic phosphide Ni₂P-Fe₂P as an efficient bifunctional catalyst for water/seawater splitting.Adv Funct Mater2021;31:2006484

[30] Jin H,Vasileff A.Single-crystal nitrogen-rich two-dimensional Mo₅N₆ nanosheets for efficient and stable seawater splitting.ACS Nano2018;12:12761-9

[31] Wang B,Chen D.Ni_xFe_yN@C microsheet arrays on Ni foam as an efficient and durable electrocatalyst for electrolytic splitting of alkaline seawater.J Mater Chem A2021;9:13562-9

[32] Gupta S,Yadav A,Patel N.Highly efficient and selective metal oxy-boride electrocatalysts for oxygen evolution from alkali and saline solutions.ACS Appl Energy Mater2020;3:7619-28

[33] Li Y,Wang J.Sandwich structured Ni3S2-MoS2-Ni3S2@Ni foam electrode as a stable bifunctional electrocatalyst for highly sustained overall seawater splitting.Electrochimica Acta2021;390:138833

[34] Wang C,Cao Z.Heterogeneous bimetallic sulfides based seawater electrolysis towards stable industrial-level large current density.Applied Catalysis B: Environmental2021;291:120071

[35] Chang J,Yang Z.Dual-doping and synergism toward high-performance seawater electrolysis.Adv Mater2021;33:e2101425

[36] Hung W,Lin T,Tsao I.A highly active selenized nickel-iron electrode with layered double hydroxide for electrocatalytic water splitting in saline electrolyte.Mater Today Energy2021;19:100575

[37] Dionigi F,Pawolek Z,Strasser P.Design criteria, operating conditions, and nickel-iron hydroxide catalyst materials for selective seawater electrolysis.ChemSusChem2016;9:962-72

[38] Liu J,Zhu Z.Engineering self-reconstruction via flexible components in layered double hydroxides for superior-evolving performance.Small2021;17:e2101671

[39] Wang W,Jiao F.(P, W)-codoped MoO₂ nanoflowers on nickel foam as an efficient bifunctional electrocatalyst for overall water splitting.Appl Surf Sci2020;529:146987

[40] Xu C,Yan L.Hierarchical molybdenum-doped cobaltous hydroxide nanotubes assembled by cross-linked porous nanosheets with efficient electronic modulation toward overall water splitting.J Colloid Interface Sci2020;562:400-8

[41] Solomon G,Mazzaro R.NiMoO₄@Co₃O₄ core-shell nanorods: in situ catalyst reconstruction toward high efficiency oxygen evolution reaction.Adv Energy Mater2021;11:2101324

[42] Zhang C,Li M.Transfer hydrogenation of nitroarenes with hydrazine at near-room temperature catalysed by a MoO₂ catalyst.Green Chem2016;18:2435-42

[43] Yu L,Mcelhenny B.Ultrafast room-temperature synthesis of porous S-doped Ni/Fe (oxy)hydroxide electrodes for oxygen evolution catalysis in seawater splitting.Energy Environ Sci2020;13:3439-46

[44] Xiong K,Gao Y.Formation of a thin-layer of nickel hydroxide on nickel phosphide nanopillars for hydrogen evolution.Electrochem commun2018;92:9-13

[45] Wu J,Liu Y,Meng X.Facile assembly of Ni(OH)₂ nanosheets on nitrogen-doped carbon nanotubes network as high-performance electrocatalyst for oxygen evolution reaction.J Alloys Compd2018;731:766-73

[46] Zhuang S,Wang H.The P/NiFe doped NiMoO₄ micro-pillars arrays for highly active and durable hydrogen/oxygen evolution reaction towards overall water splitting.Int J Hydrogen Energy2019;44:24546-58

[47] Li YK,Lu WT.Amorphous Ni-Fe-Mo suboxides coupled with Ni network as porous nanoplate array on nickel foam: a highly efficient and durable bifunctional electrode for overall water splitting.Adv Sci (Weinh)2020;7:1902034 PMCID:PMC7141049

[48] Zhang H,Hähnel A.Bifunctional heterostructure assembly of NiFe LDH nanosheets on NiCoP nanowires for highly efficient and stable overall water splitting.Adv Funct Mater2018;28:1706847

[49] Wang F,Tian W.P-Doped NiMoO₄ parallel arrays anchored on cobalt carbonate hydroxide with oxygen vacancies and mass transfer channels for supercapacitors and oxygen evolution.J Mater Chem A2019;7:19589-96

[50] Anjaneyulu U,Vijayalakshmi U.Snail shell derived natural hydroxyapatite: effects on NIH-3T3 cells for orthopedic applications.Mater Manuf Process2015;31:206-16