ACS Applied Materials & Interfaces
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2025
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IF 8.2
Qi Wang,Kaini Zhang,Zhengqi Zhang,Xin Chen,Hao Deng,Weibo Hua,Jinjia Wei,Shaohua Shen,Jie Chen
Reducing iridium (Ir) loading while maintaining efficiency and stability is crucial for the acidic oxygen evolution reaction (OER). In this study, we develop a synthetic method of sequential electrochemical deposition and high-temperature thermal shock to produce an IrOx/Ir-WO3 electrocatalyst with ∼1.75 nm IrOx nanoparticles anchoring on Ir-doped WO3 nanosheets. The IrOx/Ir-WO3 electrocatalyst with a low Ir loading of 0.035 mg cm–2 demonstrates a low overpotential of 239 mV to achieve a current density of 10 mA cm–2 and a mass activity of 6.6 × 104 A gIr–1 @1.75 V vs RHE in 0.5 M H2SO4. IrOx/Ir-WO3 on carbon paper as the anode and Pt/C as the cathode work stably for 40 h at 30 mA cm–2 in a proton exchange membrane water electrolyzer. It is found that the cooperation of lattice-doped Ir and surface-anchored IrOx enhances the activity and stability of IrOx/Ir-WO3 for acidic OER. Specifically, the doped Ir reduces the electron density of the anchored IrOx, thus optimizing the adsorption energy of oxygen-containing intermediates and the kinetic barrier of H2O dissociation, leading to an enhanced activity of IrOx/Ir-WO3. Also, the Ir-WO3 support provides electrons to retard the overoxidation and dissolution of Ir atoms from the anchored IrOx during acidic OER.
研究领域:
材料科学
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电化学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Jiahao Yang,Zhaoping Shi,Yibo Wang,Hongxiang Wu,Jing Ni,Pengbo Wang,Meiling Xiao,Changpeng Liu,Wei Xing
Despite proton exchange membrane water electrolysis (PEMWE) being a commercially viable method for high-purity hydrogen production, the development of active and robust anode electrocatalysts with reduced iridium loading under high current density conditions remains highly challenging. Here, we report a core-shell nanostructured catalyst with a metallic titanium core uniformly covered by Ir nanoparticles (Ti@Ir). The spontaneously formed TiO x layer can effectively disperse Ir nanoparticles via interfacial Ti-O-Ir bonds, which in turn increases the oxidation state of Ir towards activated lattice oxygen reactivity, as confirmed by in-situ differential electrochemical mass spectrometry (DEMS). As a result, the Ti@Ir exhibits an overpotential of only 272 mV to reach 10 mA cm −2 , 17 mV lower than non-supported Ir nanoparticles, and a 3.82-fold higher mass activity at 1.53 V. Moreover, the Ti@Ir catalyst demonstrates strong stability during a 100-hour test at 10 mA cm −2 . Detailed analysis reveals that the oxidation of iridium close to the titanium core is suppressed. The huge potential for practical application is further confirmed in a PEMWE prototype, with a low iridium loading of 0.5 mg Ir cm −2 , significantly lower than the typical 2 ∼ 4 mg Ir cm −2 required for traditional catalysts. This Ti@Ir catalyst achieves a cell voltage of 1.858 V at an industrial-level current density of 2 A cm −2 and maintains stable operation for 1800 h with an exceptionally low voltage degradation rate of only 1.252 μV h −1 .
研究领域:
材料科学
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能源技术
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电化学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Zuobo Yang,Xiaokuan Wu,Leilei Cai,Jimmy Yun,Jie Zhang,Xin Liang,Hong Zhao
Proton-exchange membrane water electrolysis (PEMWE) holds great promise for hydrogen production applications. However, the reliance of PEMWE membrane electrodes on high loadings of expensive iridium poses a significant barrier to their commercial viability. Therefore, the development of high-performance oxygen evolution catalysts with a low iridium content is of critical importance. In this research, a porous antimony tin oxide (ATO) conductive support with a particle assembly aggregate structure was fabricated by a carbon template removal method. ATO-supported IrO2 exhibits significantly improved oxygen evolution reaction (OER) activity, with a much lower overpotential compared to the unsupported IrO2 catalyst. Moreover, it achieves 1.8 V at 2 A cm–2 with an ultralow loading of iridium (0.3 mgIr cm–2) for the proton-exchange membrane electrolyzer. Characterization techniques and density functional theory calculations have elucidated that the enhanced performance is attributed to the porous morphology of ATO and the strong metal oxide–support interaction between IrO2 and the ATO support. These findings validate the practicality of conductive nanostructured antimony-tin-oxide-supported catalysts for PEMWE applications and offer a pathway for the design of low-Ir OER catalysts.
研究领域:
材料科学
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电化学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yuhua Xie,Xinxin Yu,Xianwei Li,Xue Long,Chaofeng Chang,Zehui Yang
The industrialization of solid polymer electrolyte water electrolysis (SPEWE) dominantly relies on electrocatalyst with high stability and efficiency for oxygen evolution reaction (OER) catalysis. In this work, we report a facile method to construct α-Ni(OH) 2 @Ir core–shell nanoparticles as bifunctional electrocatalyst for acidic overall water splitting application. α-Ni(OH) 2 @Ir requires lower overpotentials (238 mV and 20 mV) to achieve 10 mA cm −2 in acidic OER and HER catalysis compared to benchmarked IrO 2 (332 mV) and Pt/C (36 mV); meanwhile, the OER mass activity at 1.55 V vs. RHE was 92 fold higher than IrO 2 ; HER mass activity at overpotential of 80 mV was 5 fold better than Pt/C. The boosted catalytic activity is due to the enhanced utilization efficiency of Ir stemmed from the ultrathin Ir shell (~1 nm). Moreover, 1.49 V is demanded for α-Ni(OH) 2 @Ir to attain 10 mA cm −2 in acidic overall water splitting, 110 mV lower than benchmarked Pt/C-IrO 2 system. Meanwhile, stable catalytic performance is recorded for 20 h.
研究领域:
材料科学
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电化学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
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IF 6.7
Yiqiang Sun,Chenchen Wang,Yong Wang,Yuan Xu,Xiaodong Yang,Bo Ouyang,Cuncheng Li
Water splitting, one of the primary strategies for advancing the utilization of hydrogen production, necessitates the input of external energies to initiate the reaction due to its thermodynamically uphill nature. Nevertheless, Ru-based compounds, which were widely used as benchmark anodic catalysts, facing significant drawbacks such as their susceptibility to dissolution, significantly restrict the overall water splitting efficiency. In this work, we introduce an approach for functionalization through combining Ru nanospheres with Ir to form a Ru@Ir core–shell structure (denoted as Ru@Ir core–shell NSs), which can activate the superior oxygen evolution reaction (OER) catalytic activity, and simultaneously inherit the hydrogen evolution reaction (HER) performance in all-pH condition. The work function difference between Ru and Ir promotes the necessary energetic impetus for electron migration from Ru to Ir, resulting in the charge redistribution. Density functional theory (DFT) calculations confirmed that the Ir shell, acting as an electron acceptor, could effectively trigger electron rearrangement, augmenting the ligand affinity of hydrogen and oxygen intermediates to attain the most favorable energy states, thereby accelerating the kinetics of hydrogen and oxygen evolution. Our suggested core–shell structure approach for manipulating interface charge distribution might find utility in creating other electrocatalysts for water splitting.
研究领域:
材料科学
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能源化学
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表面科学
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DOI
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 21
·7431
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IF 4.927
Caimei Zhang,Wenjuan Zhang,Yiran Wu,Bo Peng,Chunyuan Tian,Feng Luan,Wen Sun,Xuming Zhuang,Lijun Zhao
With several major polarity and weak optical properties, the sensitive detection of HCOOH remains a major challenge. Given the special role of HCOOH in assisting in the catalytic hydrogenation process of Ir complexes, HCOOH (as a hydrogen source) could rapidly activate Ir complexes as catalysts and further reduce the substrates. This work developed a facile and sensitive HCOOH fluorescence sensor utilizing an optimal catalytic fluorescence generation system, which consists of the phenyl-pyrazole-type Ir-complex PP-Ir-Cl and the coumarin-type fluorescence probe P-coumarin. The sensor demonstrates excellent sensitivity and specificity for HCOOH and formates; the limits of detection for HCOOH, HCOONa, and HCOOEt3N were tested to be 50.6 ppb, 68.0 ppb, and 146.0 ppb, respectively. Compared to previous methods, the proposed sensor exhibits good detection accuracy and excellent sensitivity. Therefore, the proposed HCOOH sensor could be used as a new detection method for HCOOH and could provide a new design path for other sensors.Keywords:HCOOH detection;Ir complexes;catalytic hydrogenation;fluorescence probe
研究领域:
分析化学
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催化
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传感器
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2025
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IF 8.2
Xiaoping Ma,Xiaoman Zhang,Yi He,Lei Huang,Zhuo Chen,Zhihan Xu,Tianyuan Huang,Yu Xin
Reasonably developing and designing bifunctional electrocatalysts with high activity is crucial for continuously obtaining hydrogen fuel during the overall water-splitting process. Earth-abundant spinel nickel cobaltite materials have been investigated as promising oxygen evolution reaction (OER) catalysts in alkaline solution. However, its insufficient performance in the hydrogen evolution reaction (HER) significantly restricts its applicability in integrated water-splitting systems. In this study, a cationic doping and plasma nitriding strategy is employed to synthesize Ir- and N-codoped nickel cobaltite (N-IrNiCoO/CC) as a highly efficient bifunctional electrocatalyst. The incorporation of Ir and N dopants effectively modifies the electronic structure, introduces abundant oxygen vacancies, and enhances the electrical conductivity, thereby substantially improving the catalytic activity. Consequently, the optimized N-IrNiCoO/CC electrode exhibits outstanding bifunctional performance, requiring low overpotentials of 46 mV for HER and 203 mV for OER at a current density of 10 mA cm–2. Assembled in a two-electrode configuration, the N-IrNiCoO/CC||N-IrNiCoO/CC electrolyzer delivers a low cell voltage of 1.46 V at 10 mA cm–2, outperforming commercial Pt/C||Ir/C (1.67 V). Moreover, the electrolyzer retains over 97% of its initial activity after 50 h of operation at 50 mA cm–2, despite a low Ir loading of only 1.36 wt %. These results highlight the strong potential of N-IrNiCoO/CC as a cost-effective and high-performance electrocatalyst for sustainable hydrogen production.
研究领域:
电化学
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催化
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纳米材料
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能量转换
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氢气生产
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
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2020
·Vol. 45
·期 4
·5841-5851
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IF 3.741
Zhi Ming Wang,Peng Liu,Yan Peng Cao,Feng Ye,Chao Xu,Xiao Ze Du
Summary In this study, novel Pt-IrO 2 nanofiber catalysts for oxygen evolution reaction (OER) were successfully prepared using the electrospinning method with a high-concentration precursor solution. The composition and structure of catalysts were characterized, and the electrocatalytic performance of the nanofiber catalysts in water electrolysis was investigated from various aspects such as overpotential, charge transfer resistance, and exchange current density. Special attention was paid on the effect of Pt/Ir ratio on the electrocatalytic activity of the electrospun nanofibers. The results showed that the Pt-IrO 2 nanofiber catalysts with average fiber diameters ranging from 10 to 100 nm can be successfully obtained by the electrospinning method, and the average diameter decreased with the increase of Pt content. Since a bigger amount of IrO 2 content and a thinner fiber structure are all beneficial to the electrocatalytic performance, the Pt-IrO 2 catalysts with Pt:Ir = 1:9 and Pt:Ir = 9:1 both showed better catalytic performance for OER than the commercial IrO 2 , which was also demonstrated by the lower charge transfer resistance and higher exchange current density. As a result, the overpotentials of Pt-IrO 2 catalysts with Pt:Ir = 1:9 and Pt:Ir = 9:1 are 50 mV and 32 mV lower than the overpotential of the commercial IrO 2 at 30 mA cm −2 in 0.5 M H 2 SO 4 , respectively. The electrospun Pt-IrO 2 nanofiber catalyst with proper Pt content seems to be very promising since it can not only improve the catalytic performance and the safety of PEM electrolysis cells, but also reduce the amount of more expensive Ir in catalysts.
研究领域:
材料科学
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电化学
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纳米材料
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能源化学
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催化化学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
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2024
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IF 4.3
Xing Yang,Yongqi Liu,Xiaohui Niu,Ke Chu
Metalloporphyrin ligands themselves can participate in the redox process, making them beneficial in promoting the multielectron catalytic process of the oxygen evolution reaction (OER). However, OER catalysts synthesized by traditional chemical strategies face challenges in water electrolysis. We synthesized high-performance and stable alkaline and acidic OER electrocatalysts loaded with ultrasmall iridium clusters by taking advantage of the attraction and confinement of Ir atoms by the Ir–N bonds formed by the porphyrin cavity. The N in the porphyrin cavity forms an Ir–N bond with Ir so that Ir carries a negative charge and attracts Ir atoms to form ultrasmall Ir clusters above the cavity to adjust the electronic structure of the Ir clusters. The resulting catalyst Tpyp-Ir(IrOX) exhibits a small overpotential (242 and 259 mV) at a current density of 10 mA cm–2 in alkaline and acidic conditions and demonstrates good long-term operational stability. In addition, Tpyp-Ir(IrOX) exhibits a higher transition frequency (TOF) (1.69 O2 s–1 at 300 mV) in 1 M KOH, which is 7 times that of Ir/C.
研究领域:
材料科学
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催化化学
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能源科学
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产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2025
·Vol. 30
·期 7
·1599
·
IF 4.6
Yang Li,Ying Wang,Longbo Zhang,Yanru Zhang,Jia Guo,Yanyan Wang,Chenglong Yu,Jun He,Zhenpeng Wang,Juanjuan Han,Qian Li,Tianbin Wu,Qingli Qian,Buxing Han
CO2is a greenhouse gas and a nontoxic, easily available and renewable C1feedstock. H2is a clean and cheap reductant that can be obtained from renewable energy. Olefins are platform chemicals that can be produced from a variety of raw materials such as petroleum, coal and renewable biomass. The production of carboxylic acids by combining olefins, CO2and H2is a sustainable and very promising protocol. However, only a few advances in this topic have been achieved because novel catalysts need to be developed. In this work, we demonstrate that a simple iridium-based catalyst could efficiently promote the synthesis of C2+carboxylic acids via the reaction of olefins with CO2and H2. The reaction was effectively accelerated by a simple iridium-based catalytic system at 170 °C, which may be applied to various olefin substrates. The catalytic mechanism was studied through a series of control experiments. The findings contribute to advancing the sustainable production of valuable products by the reaction of renewable CO2and green H2with platform chemicals.
研究领域:
化学催化
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可持续化学
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有机化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2025
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IF 7.9
Weibin Chen,Zhan Lin
The development of proton exchange membrane water electrolyzers (PEMWEs) relies on the active and robust iridium (Ir)-based electrocatalysts for oxygen evolution reaction (OER) under acidic conditions. Loading low-content Ir with cobalt oxide (Co 3 O 4 ) nanocrystals has attracted considerable attention due to its reasonable price and high activity. However, their unsatisfying stability in acidic environments hinders their application. Herein, Ir atoms have been distributed differentiatedly in Co 3 O 4 to enhance the durability for acidic OER. Compared to the Co 3 O 4 with Ir uniformly doping (Ir B -Co 3 O 4 ), the reduced bulk Ir content in Ir S -Co 3 O 4 alleviates the electrooxidation process and facilitates the adsorbate-based pathway, thus stabilizing the structure of oxides during acidic OER. The optimized Ir S -Co 3 O 4 catalyst exhibits high mass activity of 1059.9 A g Ir −1 at 1.60 V vs RHE (779.6 A g Ir −1 for Ir B -Co 3 O 4 ). Importantly, Ir S -Co 3 O 4 possesses great stability without obvious activity loss after 20 h of continuous operation at 10 mA cm −2 , while the Ir B -Co 3 O 4 and Co 3 O 4 is deactivated within 8 and 4 h, respectively. This work provides a mechanistic understanding for designing lower-cost, active, and stable electrocatalysts containing a trace of Ir for OER.
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DOI
高影响因子
Journal of Energy Chemistry
·
2020
·
IF 7.216
Ruiqin Gao,Qi Zhang,Hui Chen,Xuefeng Chu,Guo-Dong Li,Xiaoxin Zou
Development of cost-effective and highly active oxygen evolution catalysts operating well in acidic media is a critical challenge in proton exchange membrane water electrolysis . Herein, we present a class of iridium-based 12L-perovskites (Ba 4 MIr 3 O 12 ; M = Pr, Bi, Nb) as novel low-iridium electrocatalysts for oxygen evolution reaction under acidic conditions. These 12L-perovskites contain trinuclear face-shared IrO 6 octahedral strings—unique subunits that are not found in the previously-reported iridium-based electrocatalysts . The catalytic activities of 12L-perovskites (Ba 4 MIr 3 O 12 ) are found to be related to the location of O 2 p -band center, which is influenced by the B-site nonprecious element ( i.e. , Pr, Bi or Nb). Our experimental results show that Ba 4 PrIr 3 O 12 is the most active electrocatalyst among the materials we synthesize, and contains 55% less iridium than the benchmark catalyst IrO 2 , while exhibiting higher catalytic activity. In the presence of Ba 4 PrIr 3 O 12 , transient leaching process of Ba and Pr takes place during electrochemical process , contributing to the surface reconstruction of the pristine catalysts. Further experimental results reveal that the formation of under-coordinated IrO x -rich surface and easier generation of active intermediate Ir V are mainly responsible for the good activity of Ba 4 PrIr 3 O 12 .
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）