Corresponding Author

Long Huang(longhuang@ynnu.edu.cn);
Shi-Gang Sun(sgsun@xmu.edu.cn)


Fuel cells are energy conversion devices that convert chemical energy directly into electricity. It has the advantages of high energy density, high utilization efficiency of fuel, clean and noiseless during working. Among all kinds of fuel cells, proton exchange membrane fuel cells (PEMFCs) are most popular since PEMFCs function at near ambient temperature, while their power densities are higher than those of other fuel cells. Currently, Pt-based nanomaterials are still the unreplaceable catalysts in commercialized PEMFCs. The lack of low-cost and high-performance cathode catalysts is still one of key factors that hampers the commercialization of PEMFCs. In this review, the structurally controlled syntheses of catalysts and their influences on the performances of oxygen reduction reaction (ORR) and membrane electrode assembly (MEA) are summarized. The performance of membrane electrode assembly (MEA) can also be adjusted by regulating the structure of catalyst layer. Special attention has been paid with a focus on the achievement of enhanced utilization of noble metal, and thus, lowering the loading of noble metals in MEA.

Graphical Abstract


proton-exchange membrane fuel cells, Pt-based catalysts, catalyst layer, membrane electrode assembly

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[1] Zhang J. PEM fuel cell electrocatalysts and catalyst layers: fundamentals and applications[M]. 2008, London: Springer.

[2] Debe M K. Electrocatalyst approaches and challenges for automotive fuel cells[J]. Nature, 2012, 486(7401): 43-51.
doi: 10.1038/nature11115 URL

[3] Fuel Cell System Cost-2015

[2021-08-05][EB/OL]. https://www.hydrogen.energy.gov/pdfs/15015_fuel_cell_system_cost_2015.pdf

[4] Van Zee J W. Proceedings of the symposium on diaphragms, separators, and ion-exchange membranes[J]. 1986. Electrochemical Society.

[5] Petrow H G, Allen R J. Finely particulated colloidal platinum compound and sol for producing the same, and method of preparation[P]. United States Patent, 3992512, 1976-11-16.

[6] Román-Martínez M C, Cazorla-Amorós D, Linares-Solano A, Delecea C S M, Yamashita H, Anpo M. Metal-support interaction in Pt/C catalysts. Influence of the support surface chemistry and the metal precursor[J]. Carbon, 1995, 33(1): 3-13.
doi: 10.1016/0008-6223(94)00096-I URL

[7] Amine K, Mizuhata M, Oguro K, Takenaka H. Catalytic activity of platinum after exchange with surface active functional groups of carbon blacks[J]. J. Chem. Soc., Faraday Trans, 1995, 91(24): 4451-4458.
doi: 10.1039/ft9959104451 URL

[8] Zeng J H, Lee J Y, Zhou W. Activities of Pt/C catalysts prepared by low temperature chemical reduction methods[J]. Appl. Catal. A - Gen., 2006, 308: 99-104.
doi: 10.1016/j.apcata.2006.04.019 URL

[9] Kim M, Park J N, Kim H, Song S, Lee W H. The preparation of Pt/C catalysts using various carbon materials for the cathode of PEMFC[J]. J. Power Sources, 2006, 163(1): 93-97.
doi: 10.1016/j.jpowsour.2006.05.057 URL

[10] Yu W Y, Tu W X, Liu H F. Synjournal of nanoscale platinum colloids by microwave dielectric heating[J]. Langmuir, 1999, 15(1): 6-9.
doi: 10.1021/la9806505 URL

[11] Li H Q, Xin Q, Li W Z, Zhou Z H, Jiang L H, Yang S H, Sun G Q. An improved palladium-based DMFCs cathode catalyst[J]. Chem. Commun., 2004, 23: 2776-2777.

[12] Zhou Z H, Wang S L, Zhou W J, Wang G X, Jiang L H, Li W Z, Song S Q, Liu J G, Sun G Q, Xin Q. Novel synjournal of highly active Pt/C cathode electrocatalyst for direct methanol fuel cell[J]. Chem. Commun., 2003, 3: 394-395.

[13] Pak Hoe L, Boaventura M, Lagarteira T, Kee Shyuan L, Mendes A. Polyol synjournal of reduced graphene oxide supported platinum electrocatalysts for fuel cells: Effect of Pt precursor, support oxidation level and pH[J]. Int. J. Hydrogen Energy, 2018, 43(35): 16998-17011.
doi: 10.1016/j.ijhydene.2018.05.147 URL

[14] Wang Y J, Zhao N, Fang B, Li H, Bi X T, Wang H. Effect of different solvent ratio (ethylene glycol/water) on the preparation of Pt/C catalyst and its activity toward oxygen reduction reaction[J]. RSC Advances, 2015, 5(70): 56570-56577.
doi: 10.1039/C5RA08068A URL

[15] Lee W D, Lim D H, Chun H J, Lee H I. Preparation of Pt nanoparticles on carbon support using modified polyol reduction for low-temperature fuel cells[J]. Int. J. Hydrogen Energy, 2012, 37(17): 12629-12638.
doi: 10.1016/j.ijhydene.2012.05.122 URL

[16] Li Y X, Zhang Z Y, Xiao Z J, Zhao G Z, Song H Y, Liu Y Q, Zeng J H. Stable and active Pt colloid preparation by modified citrate reduction and a mechanism analysis of inorganic additives[J]. J. Colloid Interface Sci., 2020, 572: 74-82.
doi: 10.1016/j.jcis.2020.03.070 URL

[17] Quinson J, Inaba M, Neumann S, Swane A A, Bucher J, Simonsen S B, Theil Kuhn L, Kirkensgaard J J K, Jensen K M Ø, Oezaslan M, Kunz S, Arenz M. Investigating particle size effects in catalysis by applying a size-controlled and surfactant-free synjournal of colloidal nanoparticles in alkaline ethylene glycol: case study of the oxygen reduction reaction on Pt[J]. ACS Catalysis, 2018, 8(7): 6627-6635.
doi: 10.1021/acscatal.8b00694 URL

[18] Zhao J, Chen W X, Zheng Y F, Li X, Xu Z D. Microwave polyol synjournal of Pt/C catalysts with size-controlled Pt particles for methanol electrocatalytic oxidation[J]. J. Mater. Sci., 2006, 41(17): 5514-5518.
doi: 10.1007/s10853-006-0276-4 URL

[19] Zhang L M, Wang Z B, Zhang J J, Sui X L, Zhao L, Han J C, Investigation on electrocatalytic activity and stability of Pt/C catalyst prepared by facile solvothermal synjournal for direct methanol fuel cell[J]. Fuel Cells, 2015, 15(4): 619-627.
doi: 10.1002/fuce.v15.4 URL

[20] Friebel D, Viswanathan V, Miller D J, Anniyev T, Ogasawara H, Larsen A H, O’Grady C P, Nørskov J K, Nilsson A. Balance of nanostructure and bimetallic interactions in Pt model fuel cell catalysts: In situ XAS and DFT study[J]. J. Am. Chem. Soc., 2012, 134(23): 9664-9671.
doi: 10.1021/ja3003765 pmid: 22616917

[21] Escudero-Escribano M, Malacrida P, Hansen M H, Vej-Hansen U G, Velázquez-Palenzuela A, Tripkovic V, Sch-iøtz J, Rossmeisl J, Stephens I E L, Chorkendorff I. Tuning the activity of Pt alloy electrocatalysts by means of the lanthanide contraction[J]. Science, 2016, 352(6281): 73-76.
doi: 10.1126/science.aad8892 pmid: 27034369

[22] Carpenter M K, Moylan T E, Kukreja R S, Atwan M H, Tessema M M. Solvothermal synjournal of platinum alloy nanoparticles for oxygen reduction electrocatalysis[J]. J. Am. Chem. Soc., 2012, 134(20): 8535-8542.
doi: 10.1021/ja300756y pmid: 22524269

[23] Cheng Z Z, Liao S, Zhou W P, Luo G S, Huang H F. Straightforward synjournal of chemically ordered Pt3Co/C nanoparticles by a solid phase method for oxygen-reduction reaction[J]. Ionics, 2021, 27(6): 2553-2560.
doi: 10.1007/s11581-021-04017-w URL

[24] Leteba G M, Wang Y C, Slater T J A, Cai R, Byrne C, Race C P, Mitchell D R G, Levecque P B J, Young N P, Holmes S M, Walton A, Kirkland A I, Haigh S J, Lang C I. Oleylamine aging of PtNi nanoparticles giving enhanced functionality for the oxygen reduction reaction[J]. Nano Lett., 2021, 21(9): 3989-3996.
doi: 10.1021/acs.nanolett.1c00706 URL

[25] Wang D, Xin H L, Hovden R, Wang H, Yu Y, Muller D A, DiSalvo F J, Abruña H D. Structurally ordered intermetallic platinum-cobalt core-shell nanoparticles with enhanced activity and stability as oxygen reduction electrocatalysts[J]. Nat. Mater., 2013, 12(1): 81-87.
doi: 10.1038/nmat3458 URL

[26] Strasser P, Koh S, Anniyev T, Greeley J, More K, Yu C, Liu Z, Kaya S, Nordlund D, Ogasawara H, Toney M F, Nilsson A. Lattice-strain control of the activity in dealloyed core-shell fuel cell catalysts[J]. Nat. Chem., 2010, 2(6): 454-460.
doi: 10.1038/nchem.623 pmid: 20489713

[27] Alinezhad A, Benedetti T M, Gloag L, Cheong S, Watt J, Chen H S, Gooding J J, Tilley R D. Controlling Pt crystal defects on the surface of Ni-Pt core-shell nanoparticles for active and stable electrocatalysts for oxygen reduction[J]. ACS Appl. Nano Mater., 2020, 3(6): 5995-6000.
doi: 10.1021/acsanm.0c01159 URL

[28] Tao L, Huang B L, Jin F D, Yang Y, Luo M C, Sun M Z, Liu Q, Gao F M, Guo S J. Atomic PdAu interlayer sandwiched into Pd/Pt core/shell nanowires achieves superstable oxygen reduction catalysis[J]. ACS Nano, 2020, 14(9): 11570-11578.
doi: 10.1021/acsnano.0c04061 pmid: 32816456

[29] Zhang Y F, Qin J, Leng D Y, Liu Q R, Xu X Y, Yang B, Yin F. Tunable strain drives the activity enhancement for oxygen reduction reaction on Pd@Pt core-shell electrocatalysts[J]. J. Power Sources, 2021, 485: 229340.
doi: 10.1016/j.jpowsour.2020.229340 URL

[30] Sasaki K, Kuttiyiel K A, Adzic R R. Designing high performance Pt monolayer core-shell electrocatalysts for fuel cells[J]. Curr. Opin. Electrochem., 2020, 21: 368-375.

[31] Zhao Y P, Tao L, Dang W, Wang L L, Xia M R, Wang B, Liu M M, Gao F M, Zhang J J, Zhao Y F. High-indexed PtNi alloy skin spiraled on Pd nanowires for highly efficient oxygen reduction reaction catalysis[J]. Small, 2019, 15(17): 1900288.
doi: 10.1002/smll.v15.17 URL

[32] Jang Y, Choi K H, Chung D Y, Lee J E, Jung N, Sung Y E. Self-assembled dendritic Pt nanostructure with high-index facets as highly active and durable electrocatalyst for oxygen reduction[J]. ChemSusChem, 2017, 10(15): 3063-3068.
doi: 10.1002/cssc.v10.15 URL

[33] Chen C, Kang Y J, Huo Z Y, Zhu Z W, Huang W Y, Xin H L, Snyder J D, Li D G, Herron J A, Mavrikakis M, Chi M F, More K L, Li Y D, Markovic N M, Somorjai G A, Yang P D, Stamenkovic V R. Highly crystalline multimetallic nanoframes with three-dimensional electrocatalytic surfaces[J]. Science, 2014, 343(6177): 1339-1343.
doi: 10.1126/science.1249061 pmid: 24578531

[34] Chen S P, Li M F, Gao M Y, Jin J B, van Spronsen M A, Salmeron M B, Yang P D. High-performance Pt-Co nano-frames for fuel-cell electrocatalysis[J]. Nano Lett., 2020, 20(3): 1974-1979.
doi: 10.1021/acs.nanolett.9b05251 URL

[35] Banham D, Ye S. Current status and future development of catalyst materials and catalyst layers for proton exchange membrane fuel cells: an industrial perspective[J]. ACS Energy Lett., 2017, 2(3): 629-638.
doi: 10.1021/acsenergylett.6b00644 URL

[36] Koh S, Toney M F, Strasser P. Activity-stability relationships of ordered and disordered alloy phases of Pt3Co electrocatalysts for the oxygen reduction reaction (ORR)[J]. Electrochim. Acta, 2007, 52(8): 2765-2774.
doi: 10.1016/j.electacta.2006.08.039 URL

[37] Mani P, Srivastava R, Strasser P. Dealloyed binary PtM3 (M = Cu, Co, Ni) and ternary PtNi3M (M=Cu, Co, Fe, Cr) electrocatalysts for the oxygen reduction reaction: Performance in polymer electrolyte membrane fuel cells[J]. J Power Sources, 2011, 196(2): 666-673.
doi: 10.1016/j.jpowsour.2010.07.047 URL

[38] Liu M Y, Hu A P, Ma Y N, Wang G L, Zou L L, Chen X H, Yang H, Nitrogen-doped Pt3Co intermetallic compound nanoparticles: A durable oxygen reduction electrocatalyst[J]. J. Electroanal. Chem., 2020, 871: 114267.
doi: 10.1016/j.jelechem.2020.114267 URL

[39] Yoo T Y, Yoo J M, Sinha A K, Bootharaju M S, Jung E, Lee H S, Lee B H, Kim J, Antink W H, Kim Y M, Lee J, Lee E, Lee D W, Cho S P, Yoo S J, Sung Y E, Hyeon T. Direct synjournal of intermetallic platinum-alloy nanoparticles Highly loaded on carbon supports for efficient electrocatalysis[J]. J. Am. Chem. Soc., 2020, 142(33): 14190-14200.
doi: 10.1021/jacs.0c05140 URL

[40] Wang F, Zhang Q, Rui Z Y, Li J, Liu J G. High-loading Pt-Co/C catalyst with enhanced durability toward the oxygen reduction reaction through surface Au modification[J]. ACS Appl. Mater. Inter., 2020, 12(27): 30381-30389.
doi: 10.1021/acsami.0c06951 URL

[41] Zhang M Y, Shi J J, Ning W S, Hou Z Y. Reduced gra-phene oxide decorated with PtCo bimetallic nanoparticles: Facile fabrication and application for base-free oxidation of glycerol[J]. Catal. Today, 2017, 298(SI): 234-240.
doi: 10.1016/j.cattod.2017.04.013 URL

[42] Li J R, Sharma S, Liu X M, Pan Y T, Spendelow J S, Chi M F, Jia Y K, Zhang P, Cullen D A, Xi Z, Lin H H, Yin Z Y, Shen B, Muzzio M, Yu C, Kim Y S, Peterson A A, More K L, Zhu H Y, Sun S H. Hard-magnet L10-CoPt nanoparticles advance fuel cell catalysis[J]. Joule, 2019, 3(1): 124-135.
doi: 10.1016/j.joule.2018.09.016 URL

[43] Tian X, Zhao X, Su Y Q, Wang L, Wang H, Dang D, Chi B, Liu H, Hensen E J M, Lou X W, Xia B Y. Engineering bunched Pt-Ni alloy nanocages for efficient oxygen reduction in practical fuel cells[J]. Science, 2019, 366(6467): 850-856.
doi: 10.1126/science.aaw7493 URL

[44] Cui C, Gan L, Li H H, Yu S H, Heggen M, Strasser P. Octahedral PtNi nanoparticle catalysts: exceptional oxygen reduction activity by tuning the alloy particle surface composition[J]. Nano Lett., 2012, 12(11): 5885-5889.
doi: 10.1021/nl3032795 URL

[45] Cui C, Gan L, Heggen M, Rudi S, Strasser P. Compositional segregation in shaped Pt alloy nanoparticles and their structural behaviour during electrocatalysis[J]. Nat. Mater., 2013, 12(8): 765-771.
doi: 10.1038/nmat3668 URL

[46] Chung Y H, Chung D Y, Jung N, Park H Y, Yoo S J, Jang J H, Sung Y E. Origin of the enhanced electrocatalysis for thermally controlled nanostructure of bimetallic nanoparticles[J]. J. Phys. Chem. C, 2014, 118(19): 9939-9945.
doi: 10.1021/jp5019982 URL

[47] Huang X Q, Zhao Z P, Chen Y, Zhu E B, Li M F, Duan X F, Huang Y. A rational design of carbon-supported dispersive Pt-based octahedra as efficient oxygen reduction reaction catalysts[J]. Energy Environ. Sci., 2014, 7(9): 2957-2962.
doi: 10.1039/C4EE01082E URL

[48] Dionigi F, Weber C C, Primbs M, Gocyla M, Bonastre A M, Spöri C, Schmies H, Hornberger E, Kühl S, Drnec J, Heggen M, Sharman J, Dunin-Borkowski R E, Strasser P. Controlling near-surface Ni composition in octahedral PtNi(Mo) nanoparticles by Mo doping for a highly active oxygen reduction reaction catalyst[J]. Nano Lett., 2019, 19(10): 6876-6885.
doi: 10.1021/acs.nanolett.9b02116 pmid: 31510752

[49] Lim J, Shin H, Kim M, Lee H, Lee K S, Kwon Y, Song D, Oh S, Kim H, Cho E. Ga-doped Pt-Ni octahedral nano-particles as a highly active and durable electrocatalyst for oxygen reduction reaction[J]. Nano Lett., 2018, 18(4): 2450-2458.
doi: 10.1021/acs.nanolett.8b00028 URL

[50] Huang X Q, Zhao Z P, Cao L, Chen Y, Zhu E B, Lin Z Y, Li M F, Yan A M, Zettl A, Wang Y M, Duan X F, Mueller T, Huang Y. High-performance transition metal-doped Pt3Ni octahedra for oxygen reduction reaction[J]. Science, 2015, 348(6240): 1230-1234.
doi: 10.1126/science.aaa8765 URL

[51] Arán-Ais R M, Dionigi F, Merzdorf T, Gocyla M, Heggen M, Dunin-Borkowski R E, Gliech M, Solla-Gullón J, Herrero E, Feliu J M, Strasser P. Elemental anisotropic growth and atomic-scale structure of shape-controlled octahedral Pt-Ni-Co alloy nanocatalysts[J]. Nano Lett., 2015, 15(11): 7473-7480.
doi: 10.1021/acs.nanolett.5b03057 pmid: 26441293

[52] Uskokovic V, Drofenik M. Reverse micelles: Inert nano-reactors or physico-chemically active guides of the capped reactions[J]. Adv. Colloid Interface Sci., 2007, 133(1): 23-34.
doi: 10.1016/j.cis.2007.02.002 URL

[53] Bedia J, Lemus J, Calvo L, Rodriguez J J, Gilarranz M A. Effect of the operating conditions on the colloidal and microemulsion synjournal of Pt in aqueous phase[J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2017, 525: 77-84.
doi: 10.1016/j.colsurfa.2017.04.046 URL

[54] Eriksson S, Nylén U, Rojas S, Boutonnet M. Preparation of catalysts from microemulsions and their applications in heterogeneous catalysis[J]. Appl. Catal. A-Gen., 2004, 265(2): 207-219.
doi: 10.1016/j.apcata.2004.01.014 URL

[55] Watanabe M, Yano H, Tryk D A, Uchida H. Highly durable and active PtCo alloy/graphitized carbon black cathode catalysts by controlled deposition of stabilized Pt skin layers[J]. J. Electrochem. Soc., 2016, 163(6): F455-F463.
doi: 10.1149/2.0331606jes URL

[56] Jayabal S, Saranya G, Geng D, Lin L Y, Meng X. Insight into the correlation of Pt-support interactions with electrocatalytic activity and durability in fuel cells[J]. J. Mater. Chem. A, 2020, 8(19): 9420-9446.
doi: 10.1039/D0TA01530J URL

[57] Li H, Chen C, Yan D F, Wang Y Y, Chen R, Zou Y Q, Wang S Y. Interfacial effects in supported catalysts for electrocatalysis[J]. J. Mater. Chem. A, 2019, 7(41): 23432-23450.
doi: 10.1039/C9TA04888J URL

[58] Li Z, Song M, Zhu W Y, Zhuang W C, Du X H, Tian L. MOF-derived hollow heterostructures for advanced electrocatalysis[J]. Coord. Chem. Rev., 2021, 439: 213946.
doi: 10.1016/j.ccr.2021.213946 URL

[59] Wang X X, Hwang S, Pan Y, Chen K, He Y, Karakalos S, Zhang H, Spendelow J S, Su D, Wu G. Ordered Pt3Co Intermetallic nanoparticles derived from metal-organic frameworks for oxygen reduction[J]. Nano Lett., 2018, 18(7): 4163-4171.
doi: 10.1021/acs.nanolett.8b00978 URL

[60] Chong L, Wen J, Kubal J, Sen F G, Zou J, Greeley J, Chan M, Barkholtz H, Ding W, Liu D J. Ultralow-loading platinum-cobalt fuel cell catalysts derived from imidazolate frameworks[J]. Science, 2018, 362(6420): 1276-1281.
doi: 10.1126/science.aau0630 pmid: 30409809

[61] Han B, Carlton C E, Kongkanand A, Kukreja R S, Theo-bald B R, Gan L, O'Malley R, Strasser P, Wagner F T, Shao-Horn Y. Record activity and stability of dealloyed bimetallic catalysts for proton exchange membrane fuel cells[J]. Energy Environ. Sci., 2015, 8(1): 258-266.
doi: 10.1039/C4EE02144D URL

[62] Xiao F, Qin X P, Xu M J, Zhu S Q, Zhang L L, Hong Y M, Choi S I, Chang Q W, Xu Y, Pan X Q, Shao M H. Impact of heat treatment on the electrochemical properties of carbon-supported octahedral Pt-Ni nanoparticles[J]. ACS Catal., 2019, 9(12): 11189-11198.
doi: 10.1021/acscatal.9b03206

[63] Kühl S, Gocyla M, Heyen H, Selve S, Heggen M, Dunin-Borkowski R E, Strasser P. Concave curvature facets benefit oxygen electroreduction catalysis on octahedral shaped PtNi nanocatalysts[J]. J. Mater. Chem. A, 2019, 7(3): 1149-1159.
doi: 10.1039/C8TA11298C URL

[64] Wang T Y, Liang J S, Zhao Z L, Li SZ, Lu G, Xia Z C, Wang C, Luo J H, Han J T, Ma C, Huang Y H, Li Q. Sub-6 nm fully ordered L10-Pt-Ni-Co nanoparticles enhance oxygen reduction via Co doping induced ferromagnetism enhancement and optimized surface strain[J]. Adv. Energy Mater., 2019, 9(17): 1803771.
doi: 10.1002/aenm.v9.17 URL

[65] Sun R L, Xia Z X, Xu X L, Deng R Y, Wang S L, Sun G Q. Periodic evolution of the ionomer/catalyst interfacial structures towards proton conductance and oxygen transport in polymer electrolyte membrane fuel cells[J]. Nano Energy, 2020, 75: 104919.
doi: 10.1016/j.nanoen.2020.104919 URL

[66] Uchida M, Aoyama Y, Eda N, Ohta A. New preparation method for polymer-electrolyte fuel cells[J]. J. Electrochem. Soc., 1995, 142(2): 463-468.
doi: 10.1149/1.2044068 URL

[67] Shin S J, Lee J K, Ha H Y, Hong S A, Chun H S, Oh I H. Effect of the catalytic ink preparation method on the performance of polymer electrolyte membrane fuel cells[J]. J. Power Sources, 2002, 106(1): 146-152.
doi: 10.1016/S0378-7753(01)01045-X URL

[68] Van Cleve T, Khandavalli S, Chowdhury A, Medina S, Pylypenko S, Wang M, More K L, Kariuki N, Myers D J, Weber A Z, Mauger S A, Ulsh M, Neyerlin K C. Dictating Pt-based electrocatalyst performance in polymer electrolyte fuel cells, from formulation to application[J]. ACS Appl. Mater. Inter., 2019, 11(50): 46953-46964.
doi: 10.1021/acsami.9b17614

[69] Xu F, Zhang H, Ilavsky J, Stanciu L, Ho D, Justice M J, Petrache H I, Xie J. Investigation of a catalyst ink dispersion using both ultra-small-angle X-ray scattering and cryogenic TEM[J]. Langmuir, 2010, 26(24): 19199-19208.
doi: 10.1021/la1028228 URL

[70] Takahashi S, Shimanuki J, Mashio T, Ohma A, Tohma H, Ishihara A, Ito Y, Nishino Y, Miyazawa A. Observation of ionomer in catalyst ink of polymer electrolyte fuel cell using cryogenic transmission electron microscopy[J]. Ele-ctrochim. Acta, 2017, 224: 178-185.

[71] Balu R, Choudhury N R, Mata J P, de Campo L, Rehm C, Hill A J, Dutta N K. Evolution of the interfacial structure of a catalyst ink with the quality of the dispersing solvent: a contrast variation small-angle and ultrasmall-angle neutron scattering investigation[J]. ACS Appl. Mater. Inter., 2019, 11(10): 9934-9946.
doi: 10.1021/acsami.8b20645 URL

[72] Wang M, Park J H, Kabir S, Neyerlin K C, Kariuki N N, Lv H, Stamenkovic V R, Myers D J, Ulsh M, Mauger S A. Impact of catalyst ink dispersing methodology on fuel cell performance using in-situ X-ray scattering[J]. ACS Appl. Energy Mater., 2019, 2(9): 6417-6427.
doi: 10.1021/acsaem.9b01037

[73] Xue Q, Yang D J, Li B, Ming P W, Zhang C M. Quantitative analysis effect of the cathode catalyst layer with various ionomer ratio on PEMFC by protonic resistance[J]. ECS Trans., 2019, 89(7): 23-28.
doi: 10.1149/08907.0023ecst URL

[74] Alink R, Singh R, Schneider P, Christmann K, Schall J, Keding R, Zamel N. Full parametric study of the influence of ionomer content, catalyst loading and catalyst type on oxygen and ion transport in PEM fuel cell catalyst layers[J]. Molecules, 2020, 25(7): 1523.
doi: 10.3390/molecules25071523 URL

[75] Shi Y, Lu Z X, Guo L L, Yan C F. Fabrication of membrane electrode assemblies by direct spray catalyst on water swollen Nafion membrane for PEM water electrolysis[J]. Int. J. Hydrogen Energy, 2017, 42(42): 26183-26191.
doi: 10.1016/j.ijhydene.2017.08.205 URL

[76] Sassin M B, Garsany Y, Gould B D, Swider-Lyons K E. Fabrication method for laboratory-scale high-performance membrane electrode assemblies for fuel cells[J]. Anal. Chem., 2017, 89(1): 511-518.
doi: 10.1021/acs.analchem.6b03005 pmid: 28105824

[77] Vierrath S, Breitwieser M, Klingele M, Britton B, Holdcroft S, Zengerle R, Thiele S. The reasons for the high power density of fuel cells fabricated with directly deposited membranes[J]. J. Power Sources, 2016, 326: 170-175.
doi: 10.1016/j.jpowsour.2016.06.132 URL

[78] Wei Z X, Su K H, Sui S, He A, Du S F. High performance polymer electrolyte membrane fuel cells (PEMFCs) with gradient Pt nanowire cathodes prepared by decal transfer method[J]. Int. J. Hydrogen Energy, 2015, 40(7): 3068-3074.
doi: 10.1016/j.ijhydene.2015.01.009 URL

[79] Zheng Z F, Yang F, Lin C, Zhu F J, Shen S Y, Wei G H, Zhang J L. Design of gradient cathode catalyst layer (CCL) structure for mitigating Pt degradation in proton exchange membrane fuel cells (PEMFCs) using mathematical method[J]. J. Power Sources, 2020, 451: 227729.
doi: 10.1016/j.jpowsour.2020.227729 URL

[80] Chen G Y, Wang C, Lei Y J, Zhang J, Mao Z, Mao Z Q, Guo J W, Li J, Ouyang M. Gradient design



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