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1.
Kunhong Jiang Yong Jiang Zhong Liang Chao Gu Zhurui Shen Yaping Du 《Advanced functional materials》2024,34(52):2411094
Rare earth (RE)-based perovskites are considered as promising platform for oxygen evolution reaction (OER) due to their low cost and tunable structures. However, the systematic synthesis of perovskite catalysts with satisfactory performance has rarely been reported. Herein, a general synthetic protocol for RE-substituted LaCoO3 (RE-LCO) perovskites is demonstrated. Particularly, after loaded with RuO2, the as-prepared RuO2:0.2Ce-LCO hybrid structures exhibit OER performance with a low overpotential of 135 mV at 10 mA cm−2 in 1.0 m KOH, together with remarkable long-term operation, representing one of the most efficient and robust Ru-based catalysts. Comprehensive experimental results indicate that the enhanced OER mechanism is attributed to the Ce-substitution, which alters the geometric configuration of CoO6 octahedra and generates more oxygen vacancies. Furthermore, the robust interaction between Ce-LCO and RuO2 stabilizes the valence state of Ru site. Theoretical calculations corroborate that Co 3d orbitals overlap with Ce 4f orbitals near the Fermi level, greatly improving the electron transfer between Co and Ce atoms. 相似文献
2.
Hang Shi Tian-Yi Dai Wu-Bin Wan Zi Wen Xing-You Lang Qing Jiang 《Advanced functional materials》2021,31(28):2102285
Designing robust and cost-effective electrocatalysts based on Earth-abundant elements is crucial for large-scale hydrogen production through electrochemical water splitting. Here, nitrogen-doped carbon engrafted Mo2N/CoN hybrid nanosheets that are seamlessly oriented on hierarchical nanoporous Cu scaffold (Mo-/Co-N-C/Cu), as highly efficient electrocatalysts for alkaline hydrogen evolution reaction are reported. The constituent heterostructured Mo2N/CoN nanosheets work as bifunctional electroactive sites for both water dissociation and adsorption/desorption of hydrogen intermediates while the nitrogen-doped carbon bridges electron transfers between electroactive sites and interconnective Cu current collectors by making use of Mo-/Co-N-C bonds and intimate C/Cu contacts at interfaces. As a consequence of unique architecture having electroactive sites to be sufficiently accessible, self-supported nanoporous Mo-/Co-N-C/Cu hybrid electrodes exhibit outstanding electrocatalysis in 1 m KOH, with a negligible onset overpotential and a low Tafel slope of 47 mV dec−1. They only take overpotential of as low as 230 mV to reach current density of 1000 mA cm−2. When coupled with their electro-oxidized derivatives that mediate efficiently the oxygen evolution reaction, the alkaline water electrolyzer can achieve ≈100 mA cm−2 at 1.622 V in 1 m KOH electrolyte, ≈0.343 V lower than the device constructed with commercially available Pt/C and Ir/C nanocatalysts immobilized on nanoporous Cu electrodes. 相似文献
3.
Tao Sun Wenjie Zang Jianguo Sun Chenguang Li Jun Fan Enzhou Liu John Wang 《Advanced functional materials》2023,33(30):2301526
Non-carbon-supported single-atom electrocatalysts (SACs) have attracted tremendous research interest for water splitting, owning to their remarkable differences in bond and coordination, and better and tunable catalytic performance, compared with those carbon-supported SACs and commercial catalysts. The electrocatalytic performance of these non-carbon-supported SACs is intimately related to the structure, surficial chemical groups, and vacancy defects of non-carbon host materials, as well as the physico-chemical properties and population of single atoms. The much widened range of host materials and types of single atoms create virtually limitless opportunities in the design of SACs with tunable structures and electrocatalysis behaviors. In this review, the recent progress of non-carbon-supported SACs for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is visited, where the unique local structures, electrocatalytic performance, catalytic centers and key preparation processes are presented. The characterizations down to atomic scales that can reveal the key local structures and catalytic mechanism are also investigated. New insights into the correlations between the structural evolution of these SACs during electrocatalytic reactions and their catalytic performance are examined. Finally, the major challenges faced by these new SACs are summarized, together with future perspectives on the rational design of superior non-carbon-supported SACs. 相似文献
4.
Hang Shi Xin-Ying Sun Yang Liu Shu-Pei Zeng Qing-Hua Zhang Lin Gu Tong-Hui Wang Gao-Feng Han Zi Wen Qian-Rong Fang Xing-You Lang Qing Jiang 《Advanced functional materials》2023,33(19):2214412
Developing high-efficiency and cost-effective alloy catalysts toward hydrogen-evolution reaction (HER) is crucial for large-scale hydrogen production via electrochemical water splitting, but conventional single-principal-element alloy design usually causes insufficient activity and durability of state-of-the-art multimetallic catalysts based on non-precious transition metals. Herein, we report multicomponent intermetallic Mo(NiFeCo)4 nanoparticles seamlessly integrated on hierarchical nickel network (Mo(NiFeCo)4/Ni) as robust hydrogen-evolution electrocatalysts with remarkably improved activity and durability by making use of iron and cobalt atoms partially substituting nickel sites to form high-entropy NiFeCo sublattice in intermetallic MoNi4 matrix, which serve as bifunctional electroactive sites for both water dissociation and adsorption/combination of hydrogen intermediate and improves thermodynamic stability. By virtue of bicontinuous nanoporous nickel skeleton facilitating electron/ion transportation, self-supported nanoporous Mo(NiFeCo)4/Ni electrode exhibits exceptional HER electrocatalysis, with low Tafel slope (≈35 mV dec−1), high current density (≈2300 mA cm−2) at low overpotential (200 mV) and long-term durability in 1 m KOH. When coupled to its electrooxidized and nitrified derivative for oxygen-evolution reaction, their alkaline water electrolyzers operate with a superior overall water-splitting output, outperforming the one constructed with commercially available noble-metal-based catalysts. These electrochemical properties make it an attractive candidate as electrocatalyst in alkaline water electrolysis for large-scale hydrogen generation. 相似文献
5.
Qingren Zhang Tongtong Liu Hengyu Guo Yanan Chen Yajing Di Zhengping Zhang Feng Wang 《Advanced functional materials》2024,34(3):2306176
Pyrochlore ruthenates are highlighted as candidates to replace iridium oxide as oxygen evolution reaction (OER) electrocatalyst, but their designable geometric configurations and composition modulations are hampered by the high-temperature (≈1100 °C) and long-time calcination (more than 12 h), which further decreases the technical and economic feasibility. In this work, an energy- and time-saving approach is proposed to prepare pyrochlore yttrium ruthenate at a much lower calcination temperature (600 °C) and shorter calcination time (6 h) just by inducing A-site substitutions of lead ions (YPRO). The local microstrain derived from Pb provides the surficial compression and extra driving force to overcome the strain energy of phase-transition resistances and the obtained low-temperature YPRO exhibits enriched pores, deficient geometries, shortened Ru─O bond, and enlarged Ru─O─Ru bond angle, which further modify the electronic structure, involving of the rearranged band alignment and the eliminated bandgap. The regulated morphologic, geometric, and electronic structures in YPRO synergically boost the electrocatalytic OER performance (4.8-fold and 30.0-fold enhancements compared with pyrochlore yttrium ruthenate and commercial iridium dioxide (IrO2), respectively) in universal pH conditions. This substitution-induced strain engineering on phase transition should also be effective for other high-temperature materials and trigger their diverse intriguing properties. 相似文献
6.
Electrocatalyts: Controlled Fabrication of Hierarchically Structured Nitrogen‐Doped Carbon Nanotubes as a Highly Active Bifunctional Oxygen Electrocatalyst (Adv. Funct. Mater. 9/2017) 
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下载免费PDF全文 Xianglong Zhao Feng Li Ruining Wang Jeong‐Min Seo Hyun‐Jung Choi Sun‐Min Jung Javeed Mahmood In‐Yup Jeon Jong‐Beom Baek 《Advanced functional materials》2017,27(9)
7.
Wence Xu Guilan Fan Shengli Zhu Yanqin Liang Zhenduo Cui Zhaoyang Li Hui Jiang Shuilin Wu Fangyi Cheng 《Advanced functional materials》2021,31(48):2107333
Seawater electrolysis under alkaline conditions presents an attractive alternative to traditional freshwater electrolysis for mass sustainable high-purity hydrogen production. However, the lack of active and robust electrocatalysts severely impedes the industrial application of this technology. Herein, carbon-doped nanoporous cobalt phosphide (C-Co2P) prepared by electrochemical dealloying is reported as an electrocatalyst for hydrogen evolution reaction (HER). The C-Co2P achieves an overpotential of 30 mV at a current density of 10 mA cm−2 in 1 m KOH, along with impressive catalytic activity and stability at large current densities in artificial alkaline seawater electrolyte containing mixed chlorides of NaCl, MgCl2, and CaCl2. Experimental analysis and density functional theory calculations reveal that the C atom with strong electronegativity and small atomic radius can tailor the electronic structure of Co2P, leading to weakened Co–H bonding toward promoted HER kinetics. Moreover, the C doping introduces a two-stepped H delivery pathway by forming C–Had intermediate, thus reducing the energy barrier of water dissociation. This study offers a new vision toward the development of seawater electrolysis for large-scale hydrogen production. 相似文献
8.
Xianglong Zhao Feng Li Ruining Wang Jeong‐Min Seo Hyun‐Jung Choi Sun‐Min Jung Javeed Mahmood In‐Yup Jeon Jong‐Beom Baek 《Advanced functional materials》2017,27(9)
Hierarchically structured nitrogen‐doped carbon nanotube (NCNT) composites, with copper (Cu) nanoparticles embedded uniformly within the nanotube walls and cobalt oxide (CoxOy) nanoparticles decorated on the nanotube surfaces, are fabricated via a combinational process. This process involves the growth of Cu embedded CNTs by low‐ and high‐temperature chemical vapor deposition, post‐treatment with ammonia for nitrogen doping of these CNTs, precipitation‐assisted separation of NCNTs from cobalt nitrate aqueous solution, and finally thermal annealing for CoxOy decoration. Theoretical calculations show that interaction of Cu nanoparticles with CNT walls can effectively decrease the work function of CNT surfaces and improve adsorption of hydroxyl ions onto the CNT surfaces. Thus, the activities of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) are significantly enhanced. Because of this benefit, further nitrogen doping, and synergistic coupling between CoxOy and NCNTs, Cu@NCNT/CoxOy composites exhibit ORR activity comparable to that of commercial Pt/C catalysts and high OER activity (outperforming that of IrO2 catalysts). More importantly, the composites display superior long‐term stability for both ORR and OER. This simple but general synthesis protocol can be extended to design and synthesis of other metal/metal oxide systems for fabrication of high‐performance carbon‐based electrocatalysts with multifunctional catalytic activities. 相似文献
9.
Lin Qiao Cong Xi Chao Li Kaiyue Zhang Qi Li Jiuhui Han Yi Ding 《Advanced functional materials》2024,34(37):2402286
Nickel has risen as a viable and cost-effective substitute to noble metal catalysts in electrochemical hydrogen production, yet developing air-stable and highly efficient nanostructured nickel-based catalysts remains a significant challenge. Here a facile method for creating nanoporous Ni/NiO heterostructure catalysts for electrocatalytic hydrogen production is reported. The protocol employs chemical dealloying to establish a 3D bicontinuous nanoporous structure, followed by a controlled oxidation process to in situ generate uniform NiO surface layers atop the metallic nickel matrix in a self-limiting manner. This approach not only yields highly active nickel-based catalysts through a simple and controlled procedure but also effectively mitigates the auto-ignition issue inherent in nanosized Ni, thereby enhancing air stability. By leveraging the synergistic interaction between Ni-NiO co-catalysis and improved access to intensified active sites, the electrocatalysts exhibit superior performance in the hydrogen evolution reaction, markedly outperforming noble Pt/C catalysts, and high stability in alkaline environments. The exploration of self-limiting oxidation in nanostructured transition metals opens new avenues for developing advanced metal/oxide heterostructure catalysts for diverse energy applications. 相似文献
10.
Jiyi Chen Peiyuan Zhuang Yuancai Ge Hang Chu Luyin Yao Yudong Cao Zengyao Wang Mason Oliver Lam Chee Pei Dong Jianfeng Shen Mingxin Ye Pulickel M. Ajayan 《Advanced functional materials》2019,29(37)
Using vapor phase transformation to synthesize template‐directed metal–organic frameworks (MOFs) shows great promise as an approach to avoid the shortcomings of solution‐based strategies. However, among current research, either the products are confined to zeolitic imidazolate frameworks or the conversion technologies are limited to complex processes such as chemical vapor deposition. Here, a well‐designed sublimation‐vapor phase pseudomorphic transformation method is reported to fabricate vertically aligned nanosheet arrays of NiFe‐based MOFs with a uniform and controlled thickness, derived from NiFe‐layered double hydroxides. Benefiting from the optimized morphology and the high intrinsic activity originating from the synergistic coupling effect of NiFe metal clusters, the as‐prepared MOF electrocatalyst displays a superior oxygen evolution reaction performance, requiring an overpotential of 318 mV at 50 mA cm?2 with a Tafel slope of only 47 mV dec?1. Furthermore, a string of metal oxide‐MOFs are obtained, demonstrating the universality of this strategy. By observing the different stages of transformation, the transformation and growth mechanism of MOF crystals is unveiled for the first time. These findings may inspire the exploration and preparation of more species of MOFs, further broadening their application areas. 相似文献
11.
Zi-Qi Ge Jingwei Li Hui-Jian Zhang Chunbo Liu Guangbo Che Zhao-Qing Liu 《Advanced functional materials》2024,34(40):2411024
Electrocatalytic water splitting for hydrogen production still faces a bottleneck due to sluggish reactive kinetics and high reactive energy barriers. Herein, p–d orbital coupling P–Fe heterosites are constructed at Ni2P–FeNi-LDH interfaces to enhance the O─H bond cleavage of reaction intermediates H2O* and OH* for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively. The Ni2P/NiFe-LDH heterostructure shows superior HER and OER activities for alkaline water splitting with overpotentials of 230 and 270 mV at 100 mA cm−2, respectively, and even exhibits high activity for electrocatalytic alkaline seawater splitting. The interaction of P 2p and Fe 3d orbitals at Ni2P–FeNi-LDH interfaces upshifts the d-band center of Fe and downshifts the p-band center of P. This finding not only facilitates the dissociation of O─H bonds in H2O and promotes the Volmer–Heyrovsky step for HER, but also reduces the energy barrier for the rate-determining step of OER from OH* to O* transition. This work proposes a new approach to constructing p–d heterosites at heterojunctions to facilitate reactive kinetics and reduce the energy barrier for electrocatalysis. 相似文献
12.
Yu‐Rim Hong Kang Min Kim Jeong Ho Ryu Sungwook Mhin Jungin Kim Ghulam Ali Kyung Yoon Chung Sukhyun Kang HyukSu Han 《Advanced functional materials》2020,30(38)
The development of earth‐abundant and efficient oxygen evolution reaction (OER) electrocatalysts is necessary for green hydrogen production. The preparation of efficient OER electrocatalysts requires both the adsorption sites and charge transfer on the catalyst surface to be suitably engineered. Herein, the design of an electrocatalyst is reported with significantly enhanced water oxidation performance via dual‐phase engineering, which displays a high number of adsorption sites and facile charge transfer. More importantly, a simple chemical etching process enables the formation of a highly metallic transition boride phase in conjunction with the transition metal hydroxide phase with abundant adsorption sites available for the intermediates formed in the OER. In addition, computational simulations are carried out to demonstrate the water oxidation mechanism and the real active sites in this engineered material. This research provides a new material design strategy for the preparation of high‐performance OER electrocatalysts. 相似文献
13.
14.
Li An Jianrui Feng Yu Zhang Rui Wang Hanwen Liu Gui‐Chang Wang Fangyi Cheng Pinxian Xi 《Advanced functional materials》2019,29(1)
Developing bifunctional efficient electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is in high demand for the development of overall water‐splitting devices. In particular, the electrocatalytic performance can be largely improved by designing positive nanoscale‐heterojunction with well‐tuned interfaces. Herein, a novel top‐down strategy is reported to construct the oxide/sulfide heterostructures (N‐NiMoO4/NiS2 nanowires/nanosheets) as a multisite HER/OER catalyst. Starting with the NiMoO4 nanowires, nitridation in a controlled manner enables activation of Ni sites in NiMoO4 and then yields oxide/sulfide heterojunction by directly vulcanizing the highly composition‐segregated N‐NiMoO4 nanowires. The abundant epitaxial heterogeneous interfaces at atomic‐level facilitate the electron transfer from N‐NiMoO4 to NiS2, which further cooperate synergistically toward both the hydrogen and oxygen generation in alkali solution. Furthermore, with N‐NiMoO4/NiS2 grown carbon fiber cloth as the engineering electrode, the assembled N‐NiMoO4/NiS2–N‐NiMoO4/NiS2 system can deliver a current density of 10 mA cm?2 with the cell voltage of 1.60 V in the water‐splitting reaction. This current density is 3.39 times higher than that of the Pt–Ir set (2.95 mA cm?2). The excellent catalytic performance offered of N‐NiMoO4/NiS2 nanowires/nanosheets presents a great example to demonstrate the significance of interface engineering in the field of electrocatalysis. 相似文献
15.
Jie‐Song Sun Zi Wen Li‐Ping Han Zhi‐Wen Chen Xing‐You Lang Qing Jiang 《Advanced functional materials》2018,28(14)
Tremendous demands for renewable hydrogen generated from water splitting have stimulated intensive research on developing earth‐abundant, non‐noble, and versatile metal catalysts toward the hydrogen evolution reactions (HER). Here, self‐supported Cu‐Ni‐Al hybrid electrodes that are composed of electroactive Al7Cu4Ni@Cu4Ni core/shell nanocrystals seamlessly integrated in self‐supported 3D bimodal nanoporous Cu skeleton (Bi‐NP Cu/Al7Cu4Ni@Cu4Ni) as robust HER electrocatalysts in alkaline electrolyte are reported. As a result of the proper architecture, in which the Bi‐NP Cu skeleton not only facilitates both electron and electrolyte transports but also provides high specific surface areas to fully use high electrocatalytic activity of Al7Cu4Ni@Cu4Ni core/shell nanocrystals, the Bi‐NP Cu/Al7Cu4Ni@Cu4Ni hybrid catalysts exhibit a low onset overpotential of 60 mV and a small Tafel slope of 110 mV dec?1, enabling the catalytic current density of 10 mA cm?2 at a low overpotential of 139 mV. The highly stable electrochemical performance makes them promising candidates as cathode catalysts in alkaline‐based devices. 相似文献
16.
Fe3GeTe2 is a water‐ and air‐stable, metallic, and layered material. Very recently, few‐layer and single‐layer Fe3GeTe2 have been successfully exfoliated from its bulk and revealed as 2D ferromagnets (Nature 2018 , 563, 94; Nat. Mater. 2018 , 17, 778). Here, the basal plane of Fe3GeTe2 is demonstrated to be of high electrocatalytic activity towards oxygen evolution reaction (OER) without resorting to any chemical modifications, by means of systematic density functional theory computations. The Fe3GeTe2 nanosheet preserves the metallic character of the bulk, and its 2D layered structure provides abundant exposed active sites to catalyze OER. All these unique characteristics suggest that the Fe3GeTe2 nanosheet may be an excellent catalyst for electrochemical OER. More importantly, it is found that the self‐reduction of surface hydroxyl into water can significantly reduce the overpotential for OER, which greatly boosts the OER activity. This work not only reveals new mechanisms for OER but also opens the door for the application of emerging 2D ferromagnets in the field of energy storage and conversion. 相似文献
17.
Chun Cheng Yang Shi Feng Zai Yi Tong Zhou Li Du Qing Jiang 《Advanced functional materials》2019,29(27)
Rational design of non‐noble metal catalysts with robust and durable electrocatalytic activity for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is extremely important for renewable energy conversion and storage, regenerative fuel cells, rechargeable metal–air batteries, water splitting etc. In this work, a unique hybrid material consisting of Fe3C and Co nanoparticles encapsulated in a nanoporous hierarchical structure of N‐doped carbon (Fe3C‐Co/NC) is fabricated for the first time via a facile template‐removal method. Such an ingenious structure shows great features: the marriage of 1D carbon nanotubes and 2D carbon nanosheets, abundant active sites resulting from various active species of Fe3C, Co, and NC, mesoporous carbon structure, and intimate integration among Fe3C, Co, and NC. As a multifunctional electrocatalyst, the Fe3C‐Co/NC hybrid exhibits excellent performance for ORR, OER, and HER, outperforming most of reported triple functional electrocatalysts. This study provides a new perspective to construct multifunctional catalysts with well‐designed structure and superior performance for clean energy conversion technologies. 相似文献
18.
The recent advances in electrocatalysis for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), hydrogen oxidation reaction (HOR), carbon dioxide reduction reaction (CO2RR), and nitrogen reduction reaction (NRR) are thoroughly reviewed. This comprehensive review focuses on the single‐atom catalysts (SACs) including Sc, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Sn, W, Bi, Ru, Rh, Pd, Ag, Ir, Pt, and Au with single‐metal sites or dual‐metal sites. The recent development of single‐atom electrocatalysts with novel configurations and compositions is documented. The understanding of the process–structure–property relationships is highlighted. For the SACs, their electrocatalytic performance and stability in fuel cells, zinc–air batteries, electrolyzers, CO2RR, and NRR are summarized. The challenges and perspectives in the emerging field of single‐atom electrocatalysis are discussed. 相似文献
19.
Jiashun Wu Tong Yang Rong Fu Min Zhou Lixue Xia Zhaoyang Wang Yan Zhao 《Advanced functional materials》2023,33(37):2300808
Transition-metal based layered doubled hydroxides (LDH) as oxygen evolution reaction (OER) catalysts have attracted tremendous research interests. However, it is still a great challenge to strengthen the intrinsic activity of LDH. Herein, hollow CoNiFe-LDH nanocages with amorphous/crystal phase and element gradient distribution are successfully constructed through the coordinated etching and precipitation process. Utilizing the difference of solubility product constants among transition metal cations to generate the gradient distribution effect in nanocages is proposed for the first time. The distinctive element gradient distribution in hollow CoNiFe-LDH nanocages results in the composition gradient, which can provide the heterojunctions effect and play an important role in regulating morphology and electronic structure. Density functional theory calculations disclose that the synergistic effect between elements significantly regulates the electron density and enhances the conductivity. When employed as OER electrocatalysts, it exhibits a very competitive overpotential of 257 mV at 10 mA cm−2 combined with a low Tafel slope of 31.4 mV dec−1. This work represents a promising strategy to fabricate highly efficient OER catalysts for electrochemical water splitting and provides new opportunities to understand the promotion mechanism of intrinsic activity. 相似文献
20.
《Advanced functional materials》2018,28(39)
Perovskite‐structured (ABO3) transition metal oxides are promising bifunctional electrocatalysts for efficient oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). In this paper, a set of epitaxial rare‐earth nickelates (RNiO3) thin films is investigated with controlled A‐site isovalent substitution to correlate their structure and physical properties with ORR/OER activities, examined by using a three‐electrode system in O2‐saturated 0.1 m KOH electrolyte. The ORR activity decreases monotonically with decreasing the A‐site element ionic radius which lowers the conductivity of RNiO3 (R = La, La0.5Nd0.5, La0.2Nd0.8, Nd, Nd0.5Sm0.5, Sm, and Gd) films, with LaNiO3 being the most conductive and active. On the other hand, the OER activity initially increases upon substituting La with Nd and is maximal at La0.2Nd0.8NiO3. Moreover, the OER activity remains comparable within error through Sm‐doped NdNiO3. Beyond that, the activity cannot be measured due to the potential voltage drop across the film. The improved OER activity is ascribed to the partial reduction of Ni3+ to Ni2+ as a result of oxygen vacancies, which increases the average occupancy of the eg antibonding orbital to more than one. The work highlights the importance of tuning A‐site elements as an effective strategy for balancing ORR and OER activities of bifunctional electrocatalysts. 相似文献