Graphical Abstract
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The efficiency of proton exchange membrane water electrolysis (PEM-WE) for hydrogen production is heavily dependent on the noble metal iridium-based catalysts. However, the scarcity of iridium limits the large-scale application of PEM-WE. To address this issue, it is promising to select an appropriate support because it not only enhances the utilization efficiency of noble metals but also improves mass transport under high current. Herein, we supported amorphous IrOx nanosheets onto the hollow TiO2 sphere (denoted as IrOx), which demonstrated excellent performance in acidic electrolytic water splitting. Specifically, the annealed IrOx catalyst at 150 °C in air exhibited a mass activity of 1347.5 A·gIr−1, which is much higher than that of commercial IrO2 of 12.33 A·gIr−1 at the overpotential of 300 mV for oxygen evolution reaction (OER). Meanwhile, the annealed IrOx exhibited good stability for 600 h operating at 10 mA·cm−2. Moreover, when using IrOx and annealed IrOx catalysts for water splitting, a cell voltage as low as 1.485 V can be achieved at 10 mA·cm−2. The cell can continuously operate for 200 h with negligible degradation of performance.
Zhu, W. X.; Song, X. C.; Liao, F.; Huang, H.; Shao, Q.; Feng, K.; Zhou, Y. J.; Ma, M. J.; Wu, J.; Yang, H. et al. Stable and oxidative charged Ru enhance the acidic oxygen evolution reaction activity in two-dimensional ruthenium-iridium oxide. Nat. Commun. 2023, 14, 5365.
Liu, S. H.; Tan, H.; Huang, Y. C.; Zhang, Q. B.; Lin, H. P.; Li, L.; Hu, Z. W.; Huang, W. H.; Pao, C. W.; Lee, J. F. et al. Structurally-distorted RuIr-based nanoframes for long-duration oxygen evolution catalysis. Adv. Mater. 2023, 35, 2305659.
Wu, H.; Huang, Q. X.; Shi, Y. Y.; Chang, J. W.; Lu, S. Y. Electrocatalytic water splitting: Mechanism and electrocatalyst design. Nano Res. 2023, 16, 9142–9157.
Zhu, P.; Xiong, X.; Wang, D. S. Regulations of active moiety in single atom catalysts for electrochemical hydrogen evolution reaction. Nano Res. 2022, 15, 5792–5815.
Zhu, C. X.; Yang, J. R.; Zhang, J. W.; Wang, X. Q.; Gao, Y.; Wang, D. S.; Pan, H. G. Single-atom materials: The application in energy conversion. Interdiscip. Mater. 2024, 3, 74–86.
Zhang, D. F.; Li, M. N.; Yong, X.; Song, H. Q.; Waterhouse, G. I. N.; Yi, Y. F.; Xue, B. J.; Zhang, D. L.; Liu, B. Z.; Lu, S. Y. Construction of Zn-doped RuO2 nanowires for efficient and stable water oxidation in acidic media. Nat. Commun. 2023, 14, 2517.
Shi, Z. P.; Li, J.; Wang, Y. B.; Liu, S. W.; Zhu, J. B.; Yang, J. H.; Wang, X.; Ni, J.; Jiang, Z.; Zhang, L. J. et al. Customized reaction route for ruthenium oxide towards stabilized water oxidation in high-performance PEM electrolyzers. Nat. Commun. 2023, 14, 843.
Tian, C.; Liu, R.; Zhang, Y.; Yang, W. X.; Wang, B. Ru-doped functional porous materials for electrocatalytic water splitting. Nano Res. 2024, 17, 982–1002.
Zheng, X. B.; Yang, J. R.; Xu, Z. F.; Wang, Q. S.; Wu, J. B.; Zhang, E. H.; Dou, S. X.; Sun, W. P.; Wang, D. S.; Li, Y. D. Ru-Co pair sites catalyst boosts the energetics for the oxygen evolution reaction. Angew. Chem., Int. Ed. 2022, 61, e202205946.
Zheng, X. B.; Yang, J. R.; Li, P.; Wang, Q. S.; Wu, J. B.; Zhang, E. H.; Chen, S. H.; Zhuang, Z. C.; Lai, W. H.; Dou, S. X. et al. Ir-Sn pair-site triggers key oxygen radical intermediate for efficient acidic water oxidation. Sci. Adv. 2023, 9, eadi8025.
Shi, Y.; Lu, Z. X.; Guo, L. L.; Wang, Z. D.; Guo, C. Q.; Tan, H. Y.; Yan, C. F. Fabrication of IrO2 decorated vertical aligned self-doped TiO2 nanotube arrays for oxygen evolution in water electrolysis. Int. J. Hydrogen Energy 2018, 43, 9133–9143.
Genova-Koleva, R. V.; Alcaide, F.; Álvarez, G.; Cabot, P. L.; Grande, H. J.; Martínez-Huerta, M. V.; Miguel, O. Supporting IrO2 and IrRuO nanoparticles on TiO2 and Nb-doped TiO2 nanotubes as electrocatalysts for the oxygen evolution reaction. J. Energy Chem. 2019, 34, 227–239.
Wang, Y. N.; Zhang, M. C.; Kang, Z. Y.; Shi, L.; Shen, Y. C.; Tian, B. Y.; Zou, Y. C.; Chen, H.; Zou, X. X. Nano-metal diborides-supported anode catalyst with strongly coupled TaO x /IrO2 catalytic layer for low-iridium-loading proton exchange membrane electrolyzer. Nat. Commun. 2023, 14, 5119.
Shi, Z. P.; Li, J.; Jiang, J. D.; Wang, Y. B.; Wang, X.; Li, Y.; Yang, L. T.; Chu, Y. Y.; Bai, J. S.; Yang, J. H. et al. Enhanced acidic water oxidation by dynamic migration of oxygen species at the Ir/Nb2O5- x catalyst/support interfaces. Angew. Chem., Int. Ed. 2022, 61, e202212341.
Wang, Y. B.; Ma, R. P.; Shi, Z. P.; Wu, H. X.; Hou, S.; Wang, Y.; Liu, C. P.; Ge, J. J.; Xing, W. Inverse doping IrO x /Ti with weakened Ir–O interaction toward stable and efficient acidic oxygen evolution. Chem 2023, 9, 2931–2942.
Lv, H.; Wang, S.; Li, J. K.; Shao, C. F.; Zhou, W.; Shen, X. J.; Xue, M. Z.; Zhang, C. M. Self-assembled RuO2@IrO x core–shell nanocomposite as high efficient anode catalyst for PEM water electrolyzer. Appl. Surf. Sci. 2020, 514, 145943.
Dong, S.; Zhang, C. Y.; Yue, Z. Y.; Zhang, F. R.; Zhao, H.; Cheng, Q. Q.; Wang, G. L.; Xu, J. F.; Chen, C.; Zou, Z. Q. et al. Overall design of anode with gradient ordered structure with low iridium loading for proton exchange membrane water electrolysis. Nano Lett. 2022, 22, 9434–9440.
Lin, F. X.; Lv, F.; Zhang, Q. H.; Luo, H.; Wang, K.; Zhou, J. H.; Zhang, W. Y.; Zhang, W. S.; Wang, D. W.; Gu, L. et al. Local coordination regulation through tuning atomic-scale cavities of pd metallene toward efficient oxygen reduction electrocatalysis. Adv. Mater. 2022, 34, 2202084.
Zhao, Y. F.; Lu, X. F.; Wu, Z. P.; Pei, Z. H.; Luan, D. Y.; Lou, X. W. Supporting trimetallic metal-organic frameworks on S/N-doped carbon macroporous fibers for highly efficient electrocatalytic oxygen evolution. Adv. Mater. 2023, 35, 2207888.
Joo, J. B.; Lee, I.; Dahl, M.; Moon, G. D.; Zaera, F.; Yin, Y. D. Controllable synthesis of mesoporous TiO2 hollow shells: Toward an efficient photocatalyst. Adv. Funct. Mater. 2013, 23, 4246–4254.
Wu, G.; Zheng, X. S.; Cui, P. X.; Jiang, H. Y.; Wang, X. Q.; Qu, Y. T.; Chen, W. X.; Lin, Y.; Li, H.; Han, X. et al. A general synthesis approach for amorphous noble metal nanosheets. Nat. Commun. 2019, 10, 4855
Wen, Y. Z.; Chen, P. N.; Wang, L.; Li, S. Y.; Wang, Z. Y.; Abed, J.; Mao, X. N.; Min, Y. M.; Dinh, C. T.; De Luna, P. et al. Stabilizing highly active Ru sites by suppressing lattice oxygen participation in acidic water oxidation. J. Am. Chem. Soc. 2021, 143, 6482–6490
Li, R. L.; Rao, D. W.; Zhou, J. B.; Wu, G.; Wang, G. Z.; Zhu, Z. X.; Han, X.; Sun, R. B.; Li, H.; Wang, C. et al. Amorphization-induced surface electronic states modulation of cobaltous oxide nanosheets for lithium-sulfur batteries. Nat. Commun. 2021, 12, 3102.
Gao, J. J.; Xu, C. Q.; Hung, S. F.; Liu, W.; Cai, W. Z.; Zeng, Z. P.; Jia, C. M.; Chen, H. M.; Xiao, H.; Li, J. et al. Breaking long-range order in iridium oxide by alkali ion for efficient water oxidation. J. Am. Chem. Soc. 2019, 141, 3014–3023.
Sun, W.; Ma, C. L.; Tian, X. L.; Liao, J. J.; Yang, J.; Ge, C. J.; Huang, W. W. An amorphous lanthanum-iridium solid solution with an open structure for efficient water splitting. J. Mater. Chem. A 2020, 8, 12518–12525.
Li, N.; Cai, L.; Wang, C.; Lin, Y.; Huang, J. Z.; Sheng, H. Y.; Pan, H. B.; Zhang, W.; Ji, Q. Q.; Duan, H. L. et al. Identification of the active-layer structures for acidic oxygen evolution from 9R-BaIrO3 electrocatalyst with enhanced iridium mass activity. J. Am. Chem. Soc. 2021, 143, 18001–18009.
Fan, Z. L.; Ji, Y. J.; Shao, Q.; Geng, S. Z.; Zhu, W. X.; Liu, Y.; Liao, F.; Hu, Z. W.; Chang, Y. C.; Pao, C. W. et al. Extraordinary acidic oxygen evolution on new phase 3R-iridium oxide. Joule 2021, 5, 3221–3234.
Dang, Q.; Lin, H. P.; Fan, Z. L.; Ma, L.; Shao, Q.; Ji, Y. J.; Zheng, F. F.; Geng, S. Z.; Yang, S. Z.; Kong, N. N. et al. Iridium metallene oxide for acidic oxygen evolution catalysis. Nat. Commun. 2021, 12, 6007.
Kwon, T.; Hwang, H.; Sa, Y. J.; Park, J.; Baik, H.; Joo, S. H.; Lee, K. Cobalt assisted synthesis of ircu hollow octahedral nanocages as highly active electrocatalysts toward oxygen evolution reaction. Adv. Funct. Mater. 2017, 27, 1604688.
Lv, F.; Feng, J. R.; Wang, K.; Dou, Z. P.; Zhang, W. Y.; Zhou, J. H.; Yang, C.; Luo, M. C.; Yang, Y.; Li, Y. J. et al. Iridium-tungsten alloy nanodendrites as pH-universal water-splitting electrocatalysts. ACS Cent. Sci. 2018, 4, 1244–1252.
Wang, X.; Qin, Z.; Qian, J. J.; Chen, L. Y.; Shen, K. IrCo nanoparticles encapsulated with carbon nanotubes for efficient and stable acidic water splitting. ACS Catal. 2023, 13, 10672–10682.
Mu, X. Q.; Zhang, X. Y.; Chen, Z. Y.; Gao, Y.; Yu, M.; Chen, D.; Pan, H. Z.; Liu, S. L.; Wang, D. S.; Mu, S. C. Constructing symmetry-mismatched Ru x Fe3− x O4 heterointerface-supported Ru clusters for efficient hydrogen evolution and oxidation reactions. Nano Lett. 2024, 24, 1015–1023.
Mu, X. Q.; Liu, S. L.; Zhang, M. Y.; Zhuang, Z. C.; Chen, D.; Liao, Y. R.; Zhao, H. Y.; Mu, S. C.; Wang, D. S.; Dai, Z. H. Symmetry-broken Ru nanoparticles with parasitic Ru-Co dual-single atoms overcome the volmer step of alkaline hydrogen oxidation. Angew. Chem., Int. Ed. 2024, 63, e202319618.
Zhu, L. L.; Lin, H. P.; Li, Y. Y.; Liao, F.; Lifshitz, Y.; Sheng, M. Q.; Lee, S. T.; Shao, M. W. A rhodium/silicon co-electrocatalyst design concept to surpass platinum hydrogen evolution activity at high overpotentials. Nat. Commun. 2016, 7, 12272.
Mahmood, J.; Li, F.; Jung, S. M.; Okyay, M. S.; Ahmad, I.; Kim, S. J.; Park, N.; Jeong, H. Y.; Baek, J. B. An efficient and pH-universal ruthenium-based catalyst for the hydrogen evolution reaction. Nat. Nanotechnol. 2017, 12, 441–446.
Huang, X.; Zeng, Z. Y.; Bao, S. Y.; Wang, M. F.; Qi, X. Y.; Fan, Z. X.; Zhang, H. Solution-phase epitaxial growth of noble metal nanostructures on dispersible single-layer molybdenum disulfide nanosheets. Nat. Commun. 2013, 4, 1444.
Cheng, Y. F.; Lu, S. K.; Liao, F.; Liu, L. B.; Li, Y. Q.; Shao, M. W. Rh-MoS2 nanocomposite catalysts with Pt-like activity for hydrogen evolution reaction. Adv. Funct. Mater. 2017, 27, 1700359.
Feng, J. R.; Lv, F.; Zhang, W. Y.; Li, P. H.; Wang, K.; Yang, C.; Wang, B.; Yang, Y.; Zhou, J. H.; Lin, F. et al. Iridium-based multimetallic porous hollow nanocrystals for efficient overall-water-splitting catalysis. Adv. Mater. 2017, 29, 1703798.
Pu, Z. H.; Amiinu, I. S.; Kou, Z. K.; Li, W. Q.; Mu, S. C. RuP2-based catalysts with platinum-like activity and higher durability for the hydrogen evolution reaction at all pH values. Angew. Chem., Int. Ed. 2017, 56, 11559–11564.
Jiang, P.; Yang, Y.; Shi, R. H.; Xia, G. L.; Chen, J. T.; Su, J. W.; Chen, Q. W. Pt-like electrocatalytic behavior of Ru-MoO2 nanocomposites for the hydrogen evolution reaction. J. Mater. Chem. A 2017, 5, 5475–5485.