PEDOT:PSS调控质子交换膜电解水低铱载量催化层的研究

膜电极（MEA）作为质子交换膜电解水（PEMWE）的核心部件，由中间的质子交换膜和两侧的阴阳极催化层组成，是析氧反应和析氢反应的场所。由于阳极酸性、高电势的化学环境，阳极催化剂常用IrO₂或Ir。但贵金属铱矿全球储量有限，价格昂贵，是PEMWE制氢技术成本居高不下的主要原因，限制其大规模应用。因此，在保证膜电极优异的电化学性能和长期稳定性的同时降低铱载量对降低PEMWE成本至关重要。
本文通过向低铱载量催化层（0.30 mg_Ir cm^-2）中掺入导电高分子PEDOT:PSS提高其导电性，从而制备出高性能低铱载量膜电极，有利于降低PEMWE技术的成本；并通过物理表征和电化学表征结合的手段研究了PEDOT:PSS对阳极催化剂浆料的稳定性以及低铱载量膜电极的构效关系、长期稳定性和性能衰减机理的影响，为进一步提高低铱载量膜电极的电化学性能和稳定性提供一定的理论与实验指导。
与不含PEDOT:PSS的传统膜电极相比，PEDOT:PSS的掺入不仅能够提高催化剂浆料的稳定性、降低膜电极中IrO₂团聚体的尺寸、构建多孔膜电极利于水气的传输，这意味着更多的三相界面用于析氧反应，而且可以促进膜电极中的电子传导，从而降低膜电极的欧姆阻抗。当阳极Nafion/PEDOT:PSS质量比为1:1、(Nafion+PEDOT:PSS)/IrO₂质量比为10%时，制得的低铱载量膜电极的电化学性能最优异（1.68 V@1.0 A cm^-2@80℃），优于相同载量传统膜电极的性能（1.75 V@1.0 A cm^-2@80℃），这说明PEDOT:PSS的掺入能够提高低铱载量膜电极的电化学性能。
将低铱载量膜电极在1 A cm^-2、80℃下测试750 h，电化学性能最优异的膜电极的性能衰减速率为48.7 μV h^-1，略高于相同载量传统膜电极（35.2 μV h^-1）。物理表征和间歇性阻抗测试（0 h，250 h，750 h）表征结果表明低铱载量膜电极性能衰减的原因复杂多样，包括催化层结构的坍塌，催化层内成分（Nafion、PEDOT:PSS和IrO₂）的化学降解、流失等。这些现象会加速膜电极的老化，导致低铱载量膜电极内欧姆阻抗和传质阻抗的升高，从而造成其电化学性能的衰减。

Membrane electrode assembly (MEA), as the core component of proton exchange membrane water electrolysis (PEMWE), is composed of proton exchange membrane coated with anodic and cathodic catalyst layers. MEA provides the site for oxygen evolution reaction and hydrogen evolution reaction. Given the acidic and high-potential chemical environment at anode, IrO₂ and Ir are commonly used as anode catalysts. However, the limited global reserves and high cost of the noble metal iridium contribute the unreasonably high cost of PEMWE for hydrogen production technology, thus restricting its large-scale application. Therefore, reducing iridium loading in MEA without sacrificing electrochemical performance plays a critical role in lowering the cost of PEMWE.
In this work, high-performance MEAs with low iridium loadings (0.30 mg_Ir cm^-2) were prepared by incorporating the electron-conductive polymer PEDOT:PSS into the anodic catalyst layer to promote electronic conduction, which reduces the cost of PEMWE for hydrogen production technology. The effects of PEDOT:PSS on the stability of anode catalyst inks and the structure-performance relationship, long-term stability and degradation mechanism of low-iridium loading MEAs were studied by the combination of physical and electrochemical characterizations, which provide theoretical and experimental guidance for further improving the electrochemical performance and stability of low-iridium loading MEAs.
Compared with traditional MEA without PEDOT:PSS, incorporating with PEDOT:PSS into anode catalyst inks can improve the stability of inks, reduce the size of IrO₂ agglomerates and facilitate the construction of more pores for water and gas transport in MEAs, which represent more three-phase boundaries for oxygen evolution reaction. Moreover, PEDOT:PSS can promote electronic conduction within MEAs, thereby reducing the ohmic resistance. When the mass ratios of Nafion to PEDOT:PSS and (Nafion+PEDOT:PSS) to IrO₂ in anode CL are 1:1 and 10%, respectively, the electrochemical performance of this low-iridium loading MEA is optimal (1.68 V@1.0 A cm^-2@80℃), surpassing that of the traditional MEA with the same iridium loading (1.75 V@1.0 A cm^-2@80℃), indicating that the incorporation of PEDOT:PSS improves the electrochemical performance of low-iridium loading MEAs.
Low-iridium loading MEAs were tested in single cells at 1 A cm^-2 and 80℃ for 750 hours. The performance degradation rate of this MEA with the best electrochemical performance was 48.7 μV h^-1, which was slightly higher than traditional MEA with the same iridium loading (35.2 μV h^-1). The results of physical characterizations and intermittent impedance tests (0 h, 250 h, 750 h) demonstrated that the reasons for the performance degradation of low-iridium loading MEAs are complex and dynamic, including collapse of the structure of catalyst layers, chemical degradation and loss of the chemicals (Nafion, PEDOT:PSS and IrO₂) in the catalyst layers, which all accelerate the aging of MEAs. These phenomena result in the increase of both ohmic resistance and mass transport resistance of MEA, causing the performance degradation.

[1] ROGLER M, SUERMANN M, WAGNER R, et al. Advanced Method for Voltage Breakdown Analysis of PEM Water Electrolysis Cells with Low Iridium Loadings[J]. Journal of The Electrochemical Society, 2023, 170(11): 114521.
[2] YUE M L, LAMBERT H, PAHON E, et al. Hydrogen energy systems: A critical review of technologies, applications, trends and challenges[J]. Renewable & Sustainable Energy Reviews, 2021, 146: 111180.
[3] GE L, ZHANG B, HUANG W, et al. A review of hydrogen generation, storage, and applications in power system[J]. Journal of Energy Storage, 2024, 75: 109307.
[4] HU G, CHEN C, LU H T, et al. A Review of Technical Advances, Barriers, and Solutions in the Power to Hydrogen (P2H) Roadmap[J]. Engineering, 2020, 6(12): 1364-1380.
[5] OSMAN A I, MEHTA N, ELGARAHY A M, et al. Hydrogen production, storage, utilisation and environmental impacts: a review[J]. Environmental Chemistry Letters, 2022, 20(1): 153-188.
[6] PIVOVAR B, RUSTAGI N, SATYAPAL S. Hydrogen at Scale (H2@Scale): Key to a Clean, Economic, and Sustainable Energy System[J]. The Electrochemical Society Interface, 2018, 27(1): 47.
[7] CARMO M, FRITZ D L, MERGEL J, et al. A comprehensive review on PEM water electrolysis[J]. International Journal of Hydrogen Energy, 2013, 38(12): 4901-4934.
[8] SHIVA KUMAR S, LIM H. An overview of water electrolysis technologies for green hydrogen production[J]. Energy Reports, 2022, 8: 13793-13813.
[9] EL-SHAFIE M. Hydrogen production by water electrolysis technologies: A review[J]. Results in Engineering, 2023, 20: 101426.
[10] HU S, GUO B, DING S, et al. A comprehensive review of alkaline water electrolysis mathematical modeling[J]. Applied Energy, 2022, 327: 120099.
[11] BRAUNS J, TUREK T. Alkaline Water Electrolysis Powered by Renewable Energy: A Review[J]. Processes, 2020, 8: 248.
[12] ZENG K, ZHANG D. Recent progress in alkaline water electrolysis for hydrogen production and applications[J]. Progress in Energy and Combustion Science, 2010, 36(3): 307-326.
[13] HAUCH A, KüNGAS R, BLENNOW P, et al. Recent advances in solid oxide cell technology for electrolysis[J]. Science, 2020, 370(6513): eaba6118.
[14] TIETZ F, SEBOLD D, BRISSE A, et al. Degradation phenomena in a solid oxide electrolysis cell after 9000 h of operation[J]. Journal of Power Sources, 2013, 223:129-135.
[15] KAMLUNGSUA K, SU P C, CHAN S H. Hydrogen Generation Using Solid Oxide Electrolysis Cells[J]. Fuel Cells, 2020, 20(6): 644-649.
[16] DU N, ROY C, PEACH R, et al. Anion-Exchange Membrane Water Electrolyzers[J]. Chemical Reviews, 2022, 122(13): 11830-11895.
[17] LI D, MOTZ A R, BAE C, et al. Durability of anion exchange membrane water electrolyzers[J]. Energy & Environmental Science, 2021, 14(6): 3393-3419.
[18] YAN X, GU C, LI F, et al. Power to gas: addressing renewable curtailment by converting to hydrogen[J]. Frontiers in Energy, 2018, 12: 560-568.
[19] VINCENT I, LEE E-C, KIM H-M. Comprehensive impedance investigation of low-cost anion exchange membrane electrolysis for large-scale hydrogen production[J]. Scientific Reports, 2021, 11(1): 293.
[20] AN L, WEI C, LU M, et al. Recent Development of Oxygen Evolution Electrocatalysts in Acidic Environment[J]. Advanced Materials, 2021, 33(20): 2006328.
[21] GUO X, WANG Y, ZHU W, et al. Design of Superior Electrocatalysts for Proton-Exchange Membrane-Water Electrolyzers: Importance of Catalyst Stability and Evolution[J]. ChemPlusChem, 2023: e202300514.
[22] CHEN Y, LIU C, XU J, et al. Key Components and Design Strategy for a Proton Exchange Membrane Water Electrolyzer[J]. Small Structures, 2023, 4(6): 2200130.
[23] PHAM C V, ESCALERA‐LóPEZ D, MAYRHOFER K, et al. Essentials of High Performance Water Electrolyzers - From Catalyst Layer Materials to Electrode Engineering[J]. Advanced Energy Materials, 2021, 11(44): 2101998.
[24] BüHLER M, HEGGE F, HOLZAPFEL P, et al. Optimization of anodic porous transport electrodes for proton exchange membrane water electrolyzers[J]. Journal of Materials Chemistry A, 2019, 7(47): 26984-26995.
[25] TIAN B, LI Y, LIU Y, et al. Ordered Membrane Electrode Assembly with Drastically Enhanced Proton and Mass Transport for Proton Exchange Membrane Water Electrolysis[J]. Nano Letters, 2023, 23(14): 6474-6481.
[26] BüHLER M, HOLZAPFEL P, MCLAUGHLIN D, et al. From Catalyst Coated Membranes to Porous Transport Electrode Based Configurations in PEM Water Electrolyzers[J]. Journal of The Electrochemical Society, 2019, 166(14): F1070-F1078.
[27] HOLZAPFEL P, BüHLER M, VAN PHAM C, et al. Directly coated membrane electrode assemblies for proton exchange membrane water electrolysis[J]. Electrochemistry Communications, 2020, 110: 106640.
[28] JANG Y, SEOL C, KIM S M, et al. Investigation of the correlation effects of catalyst loading and ionomer content in an anode electrode on the performance of polymer electrode membrane water electrolysis[J]. International Journal of Hydrogen Energy, 2022, 47(42): 18229-18239.
[29] XU W, LU Z, SUN X, et al. Superwetting Electrodes for Gas-Involving Electrocatalysis[J]. Accounts of Chemical Research, 2018, 51(7): 1590-1598.
[30] FAN J, CHEN M, ZHAO Z, et al. Bridging the gap between highly active oxygen reduction reaction catalysts and effective catalyst layers for proton exchange membrane fuel cells[J]. Nature Energy, 2021, 6(5): 475-486.
[31] BERNT M, GASTEIGER H A. Influence of Ionomer Content in IrO2/TiO2 Electrodes on PEM Water Electrolyzer Performance[J]. Journal of The Electrochemical Society, 2016, 163(11): F3179.
[32] KANG Z, YANG G, MO J, et al. Novel thin/tunable gas diffusion electrodes with ultra-low catalyst loading for hydrogen evolution reactions in proton exchange membrane electrolyzer cells[J]. Nano Energy, 2018, 47: 434-441.
[33] KANG Z, CHEN Y, WANG H, et al. Discovering and Demonstrating a Novel High-Performing 2D-Patterned Electrode for Proton-Exchange Membrane Water Electrolysis Devices[J]. ACS Applied Materials & Interfaces, 2022, 14(1): 2335-2342.
[34] SU H, YANG C, LIU M, et al. Tensile straining of iridium sites in manganese oxides for proton-exchange membrane water electrolysers[J]. Nature Communications, 2024, 15(1): 95.
[35] GUO H, FANG Z, LI H, et al. Rational Design of Rhodium–Iridium Alloy Nanoparticles as Highly Active Catalysts for Acidic Oxygen Evolution[J]. ACS Nano, 2019, 13(11): 13225-13234.
[36] WANG Y, ZHANG M, KANG Z, et al. Nano-metal diborides-supported anode catalyst with strongly coupled TaOx/IrO2 catalytic layer for low-iridium-loading proton exchange membrane electrolyzer[J]. Nature Communications, 2023, 14(1): 5119.
[37] MöCKL M, ERNST M F, KORNHERR M, et al. Durability Testing of Low-Iridium PEM Water Electrolysis Membrane Electrode Assemblies[J]. Journal of The Electrochemical Society, 2022, 169(6): 064505.
[38] HAN B, RISCH M, BELDEN S, et al. Screening Oxide Support Materials for OER Catalysts in Acid[J]. Journal of The Electrochemical Society, 2018, 165(10): F813-F820.
[39] SHI Q, ZHU C, DU D, et al. Robust noble metal-based electrocatalysts for oxygen evolution reaction[J]. Chemical Society Reviews, 2019, 48(12): 3181-3192.
[40] ZHANG K, LIANG X, WANG L, et al. Status and perspectives of key materials for PEM electrolyzer[J]. Nano Research Energy, 2022, 1: 9120032.
[41] PUTHIYAPURA V K, MAMLOUK M, PASUPATHI S, et al. Physical and electrochemical evaluation of ATO supported IrO2 catalyst for proton exchange membrane water electrolyser[J]. Journal of Power Sources, 2014, 269: 451-460.
[42] LEWINSKI K A, VAN DER VLIET D, LUOPA S M. NSTF Advances for PEM Electrolysis - the Effect of Alloying on Activity of NSTF Electrolyzer Catalysts and Performance of NSTF Based PEM Electrolyzers[J]. ECS Transactions, 2015, 69(17):893.
[43] PHAM C V, BüHLER M, KNöPPEL J, et al. IrO2 coated TiO2 core-shell microparticles advance performance of low loading proton exchange membrane water electrolyzers[J]. Applied Catalysis B: Environmental, 2020, 269: 118762.
[44] BöHM D, BEETZ M, GEBAUER C, et al. Highly conductive titania supported iridium oxide nanoparticles with low overall iridium density as OER catalyst for large-scale PEM electrolysis[J]. Applied Materials Today, 2021, 24: 101134.
[45] ROZAIN C, MAYOUSSE E, GUILLET N, et al. Influence of iridium oxide loadings on the performance of PEM water electrolysis cells: Part II – Advanced oxygen electrodes[J]. Applied Catalysis B: Environmental, 2016, 182: 123-131.
[46] MAZúR P, POLONSKý J, PAIDAR M, et al. Non-conductive TiO2 as the anode catalyst support for PEM water electrolysis[J]. International Journal of Hydrogen Energy, 2012, 37(17): 12081-12088.
[47] ROZAIN C, MAYOUSSE E, GUILLET N, et al. Influence of iridium oxide loadings on the performance of PEM water electrolysis cells: Part I–Pure IrO2 -based anodes[J]. Applied Catalysis B: Environmental, 2016, 182: 153-160.
[48] BERNT M, SCHRAMM C, SCHRöTER J, et al. Effect of the IrOx Conductivity on the Anode Electrode/Porous Transport Layer Interfacial Resistance in PEM Water Electrolyzers[J]. Journal of The Electrochemical Society, 2021, 168(8): 084513.
[49] XU W, SCOTT K. The effects of ionomer content on PEM water electrolyser membrane electrode assembly performance[J]. International Journal of Hydrogen Energy, 2010, 35(21): 12029-12037.
[50] KUSOGLU A, WEBER A Z. New Insights into Perfluorinated Sulfonic-Acid Ionomers[J]. Chemical Reviews, 2017, 117(3): 987-1104.
[51] HEGGE F, MORONI R, TRINKE P, et al. Three-dimensional microstructure analysis of a polymer electrolyte membrane water electrolyzer anode[J]. Journal of Power Sources, 2018, 393: 62-66.
[52] REN H, TENG Y, MENG X, et al. Ionomer network of catalyst layers for proton exchange membrane fuel cell[J]. Journal of Power Sources, 2021, 506: 230186.
[53] WU X, SCOTT K, PUTHIYAPURA V. Polymer electrolyte membrane water electrolyser with Aquivion® short side chain perfluorosulfonic acid ionomer binder in catalyst layers[J]. International Journal of Hydrogen Energy, 2012, 37(18): 13243-13248.
[54] SIRACUSANO S, BAGLIO V, VAN DIJK N, et al. Enhanced performance and durability of low catalyst loading PEM water electrolyser based on a short-side chain perfluorosulfonic ionomer[J]. Applied Energy, 2017, 192: 477-489.
[55] DONG S, ZHANG C, YUE Z, et al. Overall Design of Anode with Gradient Ordered Structure with Low Iridium Loading for Proton Exchange Membrane Water Electrolysis[J]. Nano Letters, 2022, 22(23): 9434-9440.
[56] JIANG G, YU H, LI Y, et al. Low-Loading and Highly Stable Membrane Electrode Based on an Ir@WOx NR Ordered Array for PEM Water Electrolysis[J]. ACS Applied Materials & Interfaces, 2021, 13: 15073-15082.
[57] HRBEK T, KúŠ P, YAKOVLEV Y, et al. Sputter-etching treatment of proton-exchange membranes: Completely dry thin-film approach to low-loading catalyst-coated membranes for water electrolysis[J]. International Journal of Hydrogen Energy, 2020, 45(41): 20776-20786.
[58] SUN K, ZHANG S, LI P, et al. Review on application of PEDOTs and PEDOT:PSS in energy conversion and storage devices[J]. Journal of Materials Science: Materials in Electronics, 2015, 26(7): 4438-4462.
[59] RIVNAY J, INAL S, COLLINS B A, et al. Structural control of mixed ionic and electronic transport in conducting polymers[J]. Nature Communications, 2016, 7(1): 11287.
[60] FAN X, NIE W, TSAI H, et al. PEDOT:PSS for Flexible and Stretchable Electronics: Modifications, Strategies, and Applications[J]. Advanced Science, 2019, 6(19): 1900813.
[61] TINTULA K K, PITCHUMANI S, SRIDHAR P, et al. A solid-polymer-electrolyte direct methanol fuel cell (DMFC) with Pt-Ru nanoparticles supported onto poly(3,4-ethylenedioxythiophene) and polystyrene sulphonic acid polymer composite as anode[J]. Journal of Chemical Sciences, 2010, 122(3): 381-389.
[62] TINTULA K K, PITCHUMANI S, SRIDHAR P, et al. PEDOT-PSSA as an alternative support for Pt electrodes in PEFCs[J]. Bulletin of Materials Science, 2010, 33(2): 157-163.
[63] HOSSAIN J, LIU Q, MIURA T, et al. Nafion-Modified PEDOT:PSS as a Transparent Hole-Transporting Layer for High-Performance Crystalline-Si/Organic Heterojunction Solar Cells with Improved Light Soaking Stability[J]. ACS Applied Materials & Interfaces, 2016, 8(46): 31926-31934.
[64] JIANG Y, DONG X, SUN L, et al. An alcohol-dispersed conducting polymer complex for fully printable organic solar cells with improved stability[J]. Nature Energy, 2022, 7(4): 352-359.
[65] CRUZ ORTIZ E, HEGGE F, BREITWIESER M, et al. Improving the performance of proton exchange membrane water electrolyzers with low Ir-loaded anodes by adding PEDOT:PSS as electrically conductive binder[J]. RSC Advances, 2020, 10(62): 37923-37927.
[66] TAIE Z, PENG X, KULKARNI D, et al. Pathway to Complete Energy Sector Decarbonization with Available Iridium Resources using Ultralow Loaded Water Electrolyzers[J]. ACS Applied Materials & Interfaces, 2020, 12(47): 52701-52712.
[67] KHANDAVALLI S, PARK J H, KARIUKI N N, et al. Investigation of the Microstructure and Rheology of Iridium Oxide Catalyst Inks for Low-TemperaturePolymer Electrolyte Membrane Water Electrolyzers[J]. ACS Applied Materials & Interfaces, 2019, 11(48): 45068-45079.
[68] BARANY S. Polymer adsorption and electrokinetic potential of dispersed particles in weak and strong electric fields[J]. Advances in Colloid and Interface Science, 2015, 222: 58-69.
[69] ABBOTT D F, LEBEDEV D, WALTAR K, et al. Iridium Oxide for the Oxygen Evolution Reaction: Correlation between Particle Size, Morphology, and the Surface Hydroxo Layer from Operando XAS[J]. Chemistry of Materials, 2016, 28(18): 6591-6604.
[70] SHUKLA S, BHATTACHARJEE S, WEBER A Z, et al. Experimental and Theoretical Analysis of Ink Dispersion Stability for Polymer Electrolyte Fuel Cell Applications[J]. Journal of The Electrochemical Society, 2017, 164(6): F600-F609.
[71] VISWANATH B, PATRA S, MUNICHANDRAIAH N, et al. Nanoporous Pt with High Surface Area by Reaction-Limited Aggregation of Nanoparticles[J]. Langmuir, 2009, 25(5): 3115-3121.
[72] ALIA S M, STARIHA S, BORUP R L. Electrolyzer Durability at Low Catalyst Loading and with Dynamic Operation[J]. Journal of The Electrochemical Society, 2019, 166(15): F1164.
[73] MAJASAN J O, IACOVIELLO F, CHO J I S, et al. Correlative study of microstructure and performance for porous transport layers in polymer electrolyte membrane water electrolysers by X-ray computed tomography and electrochemical characterization[J]. International Journal of Hydrogen Energy, 2019, 44(36): 19519-19532.
[74] DEDIGAMA I, ANGELI P, AYERS K, et al. In situ diagnostic techniques for characterisation of polymer electrolyte membrane water electrolysers - Flow visualisation and electrochemical impedance spectroscopy[J]. International Journal of Hydrogen Energy, 2014, 39(9): 4468-4482.
[75] LI G, PICKUP P G. Ion transport in poly(3,4-ethylenedioxythiophene)–poly(styrene-4-sulfonate) composites[J]. Physical Chemistry Chemical Physics, 2000, 2(6): 1255-1260.
[76] YOSHITAKE M, TAMURA M, YOSHIDA N, et al. Studies of Perfluorinated Ion Exchange Membranes for Polymer Electrolyte Fuel Cells[J]. Denki Kagaku oyobi Kogyo Butsuri Kagaku, 1996, 64(6): 727-736.
[77] SUERMANN M, SCHMIDT T J, BüCHI F N. Cell Performance Determining Parameters in High Pressure Water Electrolysis[J]. Electrochimica Acta, 2016, 211: 989-997.
[78] CHOI S, SHIN S-H, LEE D-H, et al. Enhancing the durability of hydrocarbon-membrane-based polymer electrolyte water electrolysis using a radical scavenger-embedded interlocking interfacial layer[J]. Journal of Materials Chemistry A, 2022, 10(2): 789-798.
[79] LV H, WANG S, LI J, et al. Self-assembled RuO2@IrOx core-shell nanocomposite as high efficient anode catalyst for PEM water electrolyzer[J]. Applied Surface Science, 2020, 514: 145943.
[80] ZACCARINE S F, SHVIRO M, WEKER J N, et al. Multi-Scale Multi-Technique Characterization Approach for Analysis of PEM Electrolyzer Catalyst Layer Degradation[J]. Journal of The Electrochemical Society, 2022, 169(6): 064502.
[81] FENG Q, YUAN X Z, LIU G, et al. A review of proton exchange membrane water electrolysis on degradation mechanisms and mitigation strategies[J]. Journal of Power Sources, 2017, 366: 33-55.
[82] YU H, BONVILLE L, JANKOVIC J, et al. Microscopic insights on the degradation of a PEM water electrolyzer with ultra-low catalyst loading[J]. Applied Catalysis B: Environmental, 2020, 260: 118194.
[83] KUHNERT E, HACKER V, BODNER M. A Review of Accelerated Stress Tests for Enhancing MEA Durability in PEM Water Electrolysis Cells[J]. International Journal of Energy Research, 2023, 2023: 3183108.
[84] BAJAJ A, LIU F, KULIK H J. Uncovering Alternate Pathways to Nafion Membrane Degradation in Fuel Cells with First-Principles Modeling[J]. The Journal of Physical Chemistry C, 2020, 124(28): 15094-15106.
[85] CHEN C, LEVITIN G, HESS D W, et al. XPS investigation of Nafion® membrane degradation[J]. Journal of Power Sources, 2007, 169(2): 288-295.
[86] OKONKWO P C, BEN BELGACEM I, EMORI W, et al. Nafion degradation mechanisms in proton exchange membrane fuel cell (PEMFC) system: A review[J]. International Journal of Hydrogen Energy, 2021, 46(55): 27956-27973.
[87] YUAN X-Z, ZHANG S, BAN S, et al. Degradation of a PEM fuel cell stack with Nafion® membranes of different thicknesses. Part II: Ex situ diagnosis[J]. Journal of Power Sources, 2012, 205: 324-334.
[88] CHAABANE L, DAMMAK L, GRANDE D, et al. Swelling and permeability of Nafion®117 in water–methanol solutions: An experimental and modelling investigation[J]. Journal of Membrane Science, 2011, 377(1): 54-64.
[89] BUNKIN N F, KOZLOV V A, SHKIRIN A V, et al. Dynamics of Nafion membrane swelling in H2O/D2O mixtures as studied using FTIR technique[J]. The Journal of Chemical Physics, 2018, 148(12): 124901.
[90] RAKOUSKY C, REIMER U, WIPPERMANN K, et al. An analysis of degradation phenomena in polymer electrolyte membrane water electrolysis[J]. Journal of Power Sources, 2016, 326: 120-128.
[91] CARLI S, DI LAURO M, BIANCHI M, et al. Water-Based PEDOT: Nafion Dispersion for Organic Bioelectronics[J]. ACS Applied Materials & Interfaces, 2020, 12: 29807-29817.
[92] CHEN C, FULLER T F. The effect of humidity on the degradation of Nafion®membrane[J]. Polymer Degradation and Stability, 2009, 94(9): 1436-1447.
[93] FREAKLEY S J, RUIZ‐ESQUIUS J, MORGAN D J. The X-ray photoelectron spectra of Ir, IrO2 and IrCl3 revisited[J]. Surface and Interface Analysis, 2017, 49(8): 794-799.
[94] FRIEDMAN A K, SHI W, LOSOVYJ Y, et al. Mapping Microscale Chemical Heterogeneity in Nafion Membranes with X-ray Photoelectron Spectroscopy[J]. Journal of The Electrochemical Society, 2018, 165(11): H733-H741.
[95] WHITE W, SANBORN C D, REITER R S, et al. Observation of Photovoltaic Action from Photoacid-Modified Nafion Due to Light-Driven Ion Transport[J]. Journal of the American Chemical Society, 2017, 139(34): 11726-11733.
[96] SHI Y, ZHOU Y, CHE Z, et al. Degradation phenomena and degradation mechanisms for highly conductive PEDOT:PSS films[J]. Materials Letters, 2022, 308: 131106.
[97] BARSCH U, BECK F. Anodic overoxidation of polythiophenes in wet acetonitrile electrolytes[J]. Electrochimica Acta, 1996, 41(11): 1761-1771.
[98] JöNSSON S K M, BIRGERSON J, CRISPIN X, et al. The effects of solvents on the morphology and sheet resistance in poly(3,4-ethylenedioxythiophene)-polystyrenesulfonic acid (PEDOT-PSS) films[J]. Synthetic Metals, 2003, 139(1): 1-10.
[99] HU L, LI M, YANG K, et al. PEDOT:PSS monolayers to enhance the hole extraction and stability of perovskite solar cells[J]. Journal of Materials Chemistry A, 2018, 6(34): 16583-16589.