MICROCHIMICA ACTA
·
2022
·Vol. 190
·期 1
·1-12
·
IF 6.408
Yan Zhengquan,Zheng Xiaoyu,Meng Guoqing,Tang Yulian,Zhou Xuemei,Hao Junkai,Feng Jing,Lin Naibo,Hu Lei
A portable sensor for visual monitoring of Fe 2+ and H 2 O 2 , two-dimensional Co 3 O 4 modified by nano-IrO 2 (IrO 2 @2D Co 3 O 4 ) was prepared in this work, for the first time, with the help of microwave radiation at 140 °C, which was further stabilized onto common test strips. The present IrO 2 @2D Co 3 O 4 possessed superior dual-function enzyme-like activity with low toxicity and excellent biocompatibility. Especially, trace Fe 2+ and H 2 O 2 could exclusively alter their enzyme-like catalytic activity with discriminating hyperchromic or hypochromic effect, i.e., from blue to colorless or to dark blue for both IrO 2 @2D Co 3 O 4 dispersion and its functionalized test strips. The linear regression equations were A 652 = 0.5940 − 0.00041 c Fe 2+ (10 −8 M, R 2 = 0.9927) for Fe 2+ and ∆A 652 = 0.0023 c H2O2 + 0.00025 (10 −7 M, R 2 = 0.9982) for H 2 O 2 , respectively. When applied to visual monitoring of aqueous Fe 2+ and intercellular H 2 O 2 , the recoveries were 101.2 ~ 102.5% and 95.8 ~ 103.7% with detection limits of 1.25 × 10 −8 mol/L and 1.02 × 10 −7 mol/L, respectively, far below the permitted values in drinking water set by the World Health Organization. The mechanisms for the enhancing enzyme-mimetic activity of IrO 2 @2D Co 3 O 4 and its selective responses to Fe 2+ and H 2 O 2 were investigated in detail. Graphical Abstract
研究领域:
分析化学
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生物医学工程
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环境科学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Yahui Wang,Shaoyun Hao,Xiangnan Liu,Qiqi Wang,Zhiwei Su,Lecheng Lei,Xingwang Zhang
Electrocatalytic water splitting in acidic media based on a proton-exchange membrane (PEM) is a promising technique for the large-scale production of hydrogen. However, developing electrocatalysts with high activity and excellent stability for an oxygen evolution reaction (OER) in acidic media is still a big challenge. Herein, a Cex-IrO2 catalyst supported on N-doped porous carbon (NPC) was developed via doping Ce into IrO2 nanoparticles. The Cex-IrO2 nanoparticles were uniformly distributed on NPC due to the high surface area. The optimized Ce0.2-IrO2@NPC delivers a low overpotential of 224 mV and excellent stability of 100 h in 0.5 M H2SO4 at 10 mA cm–2. Density functional theory (DFT) calculations indicated that the introduction of Ce could modify the electronic structure of IrO2, decreasing the energy barrier of the rate-determining step for OER and enhancing the electrochemical OER performance. Our work opens up a new way of developing anodic electrocatalysts, which can be stably applied in acidic media.
研究领域:
材料科学
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电化学
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能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
·
2023
·
IF 3.7
Hongxiang Wu,Yibo Wang,Zhaoping Shi,Dongchen Han,Jiahao Yang,Pengbo Wang,Jing Ni,Meiling Xiao,Changpeng Liu,Wei Xing
The successful deployment of proton-exchange membrane water electrolyzers (PEMWEs) relies on the development of an active and durable electrocatalyst for the anodic oxygen evolution reaction (OER). Although rutile IrO2 shows excellent durability due to its stable crystal structure, it suffers from unsatisfactory activity. Here, we report a partial Sn substitution strategy to trigger lattice oxygen reactivity toward boosted OER. The similar crystal structures of IrO2 and SnO2 promote uniform incorporation of Sn into the lattice of IrO2, thus retaining the durability of the pristine rutile phase. More importantly, the electron transfer from Ir to Sn through the local structure of Ir–O–Sn was found to enhance the Ir–O bond covalency, which in turn activated the lattice oxygen to participate in OER. The enhanced lattice oxygen mechanism (LOM) was further verified by in situ 18O isotope labeling in situ differential electrochemical mass spectroscopy (DEMS). Due to these attributes, the as-designed Ir0.83Sn0.17O2 catalyst showed significantly improved performance, with an overpotential of only 284 mV at a current density of 10 mA cm–2, 38 mV lower than that of the commercial IrO2. In addition, the mass activity of the Ir0.83Sn0.17O2 catalyst reaches as high as 130 A gIr–1 at 1.55 V, which is 2.58 times higher than that of commercial IrO2. Beyond that, the intrinsic stability of the rutile phase endows the Ir0.83Sn0.17O2 catalyst with excellent operational durability. This work provides a novel insight into the improvement of catalyst activity and inspires the design of highly active and stable OER catalysts.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2019
·Vol. 97
·期 12
·3002-3011
·
IF 1.61
Jie Ren,Yi-Ling Liu,Li Feng,Chun-Wei Liu
The electrochemical preparation of NaClO has been widely used for the production of industrial disinfectant. To reduce the cost of electrode preparation using the brushing method, this paper introduces a method for the electrodeposition for RuO 2 /Ti and RuO 2 -IrO 2 /Ti preparation and NaCl solution electrolysis. The deposition of Ir improves the uniformity and stability of the RuO 2 /Ti electrode. The optimum preparation conditions and additive concentrations were investigated in detail through the orthogonal experiment. By adjusting the electroplating time, temperature and voltage, the electrode with a high content of available chlorine was synthesized successfully. The physicochemical properties of the as-prepared RuO 2 /Ti and RuO 2 -IrO 2 /Ti were determined by XRD, SEM-EDS, and XPS, and the electrochemical performance and lifetime of the RuO 2 /Ti and RuO 2 -IrO 2 /Ti was verified via an electrochemical workstation. Uniform and stable RuO 2 /TiO 2 and RuO 2 -IrO 2 /TiO 2 were synthesized successfully for the electrolysis of the NaCl solution.
研究领域:
材料科学
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电化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2016
·Vol. 92
·期 4
·827-833
·
IF 2.738
Jinxi Feng,Shenyu Lan,Chunyang Yao,Ya Xiong,Shuanghong Tian
BACKGROUND Electro-generation of NaOH and H 2 SO 4 with organic compound-free Na 2 SO 4 wastewater has been known for many years, but actually, lots of Na 2 SO 4 wastewater contains organic pollutants, such as black liquor, dyeing and sulphonating wastewater etc., therefore, there is a strong demand for investigations on performance and effect of the organic pollutants in electrochemically splitting Na 2 SO 4 into H 2 SO 4 and NaOH from these wastewaters. RESULTS Co-electrolysis of Na 2 SO4 (1.13 mol L −1 ) and AO7 (50 ∼ 500 mg L −1 ) was investigated in a diaphragm cell with IrO 2 -coated Ti electrodes. It was found that the concentrations of the resulting NaOH and H 2 SO 4 could remain at about 0.73 mol L −1 and 0.36 mol L −1 , respectively, although the COD removal was increased from 50.3 mg L −1 to 166.3 mg L −1 with the increase of AO7 concentration, for 120 min. CONCLUSION In a diaphragm cell with IrO 2 -coated Ti electrodes, NaOH and H 2 SO 4 could be effectively generated, and simultaneously, AO7 could also be degraded for the wastewater containing Na 2 SO 4 and AO7. Interestingly, the electro-generation of NaOH and H 2 SO 4 was not significantly affected by the occurrence and degradation of AO7 in the range 0–500 mg L −1 . The phenomenon of constant acid–base yield contributed to the independence of the main acid-generating reactions on the electro-oxidation of AO7. © 2016 Society of Chemical Industry
研究领域:
环境科学
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电化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2023
·
IF 4.5
Yi-heng Zhang,Lin Zhu,Xin Guo,Wen-jing Zhang,Xiang Shao,Ji Yang
The treatment of livestock wastewater is a major environmental challenge due to the presence of antibiotics from animal excreta, which may pass through conventional biological oxidation treatment and pose a threat to public health. Electro-oxidation method presents an opportunity to remove antibiotics in the livestock wastewater at the source of generation, and titanium-based IrO 2 anode has been shown to have excellent electro-catalytic activity and stability. However, the soaring price of iridium limits the practical application. In this work, we showed that W, Ti-doped IrO 2 anodes largely preserved the electro-catalytic activity while reducing the cost of electrode fabrication. The prepared Ti/Sb-SnO 2 /(Ir 0.6 W 0.2 Ti 0.2 )O x anode was shown to achieve 94 % conversion of sulfadiazine in 1 min and 100 % conversion in 15 min. Additionally, complete removal of chemical oxygen demand (COD 0 = 700–800 mg/L) was achieved in 1–3 h of electrolysis at 40 mA/cm 2 . Chlorine-mediated oxidation was demonstrated to be the main mechanism for organic contaminant degradation. The COD removal during galvanostatic electrolysis exhibited zero-order kinetics, indicating that the reaction rate was controlled by the heterogeneous reaction at the anode surface. In the stability test, >95 % COD removal was maintained after 5 cycles of electro-oxidation experiments. The accelerated life of the anode was tested to be 352 h (1000 mA/cm 2 , 1 M H 2 SO 4 electrolyte, 60 °C).
研究领域:
环境科学
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水处理工程
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电化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 48
·25687-25695
·
IF 11.301
Lei Li,Guilin Li,Yaping Zhang,Wenjun Ouyang,Huiwen Zhang,Feifei Dong,Xuehui Gao,Zhan Lin
Water splitting by electrolysis is a promising technology that can address rising energy demands and environmental pollution. However, the oxygen evolution reaction (OER), as one half-cell reaction of water splitting, always suffers from slow kinetics and a large overpotential due to the four proton-coupled electron transfer process, and dominates the overall process efficiency. IrO2 is a promising and widely used catalyst for the OER in commercial applications. Herein, we obtained low-crystalline nano-IrO2 particles confined in an amorphous Ir-based MOF (IrO2@Ir-MOF) through a simple solvothermal reaction, in which ultrafine IrO2 particles are uniformly distributed in the Ir-MOF skeleton. The fabricated IrO2@Ir-MOF-ppy electrode exhibits excellent OER activity with an overpotential of 207 mV, to achieve a current density of 10 mA cm−2 in 1 M KOH solution, outperforming most previously reported OER catalysts. The IrO2@Ir-MOF‖IrO2@Ir-MOF couple exhibits promising activity and stability for the overall water splitting reaction in 1 M KOH (1.53 V).
研究领域:
材料科学
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能源化学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2022
·
IF 5.545
Wang Chuan,Cao Zhifen,Huang Hongtao,Liu Hong,Wang Sha
Nitrate pollution is already a global problem, and the electrocatalytic reduction of nitrate is a promising technology for the remediation of wastewater and polluted water bodies. In this work, Co3O4/Ti electrodes were prepared by electrodeposition for the electrocatalytic reduction of nitrate. The morphology, chemical, and crystal structures of Co3O4/Ti and its catalytic activity were investigated. Then, the electrocatalytic nitrate reduction performance of Co3O4/Ti as the cathode was evaluated by monitoring the removal efficiencies of nitrate (NO3−-N) and total nitrogen (TN), generation of reduction products, current efficiency (CE), and energy consumption (EC) at different operating conditions. Under the catalysis of Co3O4/Ti, NO3− was reduced to N2 and NH4+, while no NO2− was produced. After the introduction of chloride ions and IrO2-RuO2/Ti as the anode, NH4+ was selectively oxidized to N2. The removal efficiencies of NO3−-N (at 100 mg/L) and TN after 2 h were 91.12% and 60.25%, respectively (pH 7.0; Cl− concentration, 2000 mg/L; current density, 15 mA/cm2). After 4 h of operation, NO3−-N and TN were completely removed. However, considering the EC and CE, a 2-h reaction was the most appropriate. The EC and CE were 0.10 kWh/g NO3−N and 40.3%, respectively, and electrocatalytic performance was maintained after 10 consecutive reduction cycles (2 h each). The cathode Co3O4/Ti, which is prepared by electrodeposition, can effectively remove NO3−-N, with low EC and high CE.
研究领域:
环境科学
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电化学工程
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废水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2025
·
IF 16
Shougang Sun,Ziqi Wan,Yingying Xu,Xuemei Zhou,Wei Gao,Jinjie Qian,Jie Gao,Dong Cai,Yongjie Ge,Huagui Nie,Zhi Yang
The engineering of dual-functional catalytic systems capable of driving complete water dissociation in acidic environments represents a critical requirement for advancing proton exchange membrane electrolyzer technology, yet significant challenges remain. In this work, we investigate an IrO2/MoS2/CNT heterostructure catalyst demonstrating enhanced bifunctional performance for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) under acidic conditions. Strategic incorporation of IrO2 into the MoS2/CNT heterojunction induces a partial phase transformation from 2H to the metastable 1T configuration in MoS2, thereby modulating the electronic structure of IrO2 and improving the catalytic performance for overall water splitting. The optimized IrO2/MoS2/CNT catalyst exhibited exceptional overpotentials of 9 mV (HER) and 182 mV (OER) at a current density of 10 mA cm–2 in acidic media. Full-cell evaluations further confirmed its practical potential, showing a 1.47 V operation voltage that outperforms standard Pt/C||IrO2 counterparts by 120 mV. The experimental results revealed that the n–n heterojunction between IrO2/CNT and MoS2/CNT generates a built-in electric field, enhancing charge redistribution and electron transport. Moreover, density functional theory simulations further identify iridium centers as dominant catalytic loci, with a metastable 1T-MoS2 phase mediating charge equilibration at atomic interfaces. This modification facilitates *OH adsorption and *OOH deprotonation and lowers the kinetic barrier during the water-splitting process.
研究领域:
材料科学
·
电化学
·
催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Danyang Wang,Shiwen Zhao,Jianke Li,Lin Shi,Yuhuan Zhang
The increasing bacterial resistance caused by the abuse of antibiotics has become an urgent global healthcare challenge. Recent advances in nanozymes represent one feasible solution. However, efforts have mainly focused on mimicking natural enzymes for comparable biocatalytic activities, as preparing nanozymes with superior antibacterial properties remains challenging. In this study, inspired by the Fe catalytic site in horseradish peroxidase (HRP), we synthesized defect-rich ruthenium oxide/iridium oxide heterojunction nanosheets (RuO 2 /IrO 2 ), using Ru, which possesses a similar electronic structure to Fe, as the catalytic site to enhance antibacterial properties. Benefiting from the typically high catalytic activity of Ru in various reactions and the unique Ir-mediated defect-rich heterostructure, RuO 2 /IrO 2 exhibits dramatically enhanced biocatalytic activities in generating reactive oxygen species crucial for eradicating bacteria. In particular, RuO 2 /IrO 2 exhibited both oxidase and peroxidase-mimicking activities with catalytic efficiency 10 3 to 10 4 times higher than that of HRP. It exhibited superior antibacterial properties as well as high biosafety , effectively eliminating H 2 O 2 toxicity during in vivo anti-infection measures. Minimum inhibitory concentration (MIC) values of RuO 2 /IrO 2 against Staphylococcus aureus and Escherichia coli were 31.25 and 15.62 μg mL −1 , respectively. This study offers a promising potential design for antibacterial nanozymes.
研究领域:
生物化学
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纳米医学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2024
·
IF 5.5
Bao Liu,Guihu Li,Xianbo Cai,Yajun Wang,Yanan Zeng,Qianqian Ren,Junguo Li
The sluggish kinetics of the oxygen evolution reaction (OER) refers to the major contributor to the energy losses in electrowinning of metals. Improving the stability in the long term and activity of the electrocatalyst for OER take on a critical significance in reducing the energy consumption. An efficient and stable OER electrode (named as Ti/SMST/IrO 2 electrode) was prepared in this study by supporting IrO 2 nanoparticles on the surface of the submicrometer-sized TiO 2 (SMST) interlayer. The obtained results indicated that the IrO 2 nanoparticles approximately 14 nm in size were supported onto the submicrometer-sized TiO 2 particles’ surface and exhibited a cactus-like morphology. The Ti/SMST/IrO 2 electrode with the SMST interlayer prepared at 450 °C exhibited the highest electrocatalytic activity in terms of OER for its largest active surface area. This electrode showed an overpotential of 350 mV at a current density of 50 mA cm −2 and displayed a remarkable electrochemical stability of 443 h at a high current density of 2 A cm −2 in H 2 SO 4 solution without significant change in OER activity. The prepared Ti/SMST/IrO 2 electrode with high electrocatalytic performance is considered one of the promising electrodes for OER.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Weiwei Han,Yang Qian,Fan Zhang,Yi He,Ping Li,Xingwang Zhang
The application of proton exchange membrane water electrolysis (PEMWE) is largely limited by the sluggish oxygen evolution reaction (OER) kinetics, which usually requires noble metal Ir/Ru-based catalysts. It’s desirable to design low-cost catalysts with less content of Ir/Ru in OER without sacrificing their catalytic performance. Herein, the ultrasmall IrO 2 nanoparticles uniformly dispersed on Co 3 O 4 -CoMoO 4 nanocages (IrO 2 @Co 3 O 4 -CoMoO 4 ) electrocatalyst is demonstrated. Structural characterization indicates that hollow Co 3 O 4 -CoMoO 4 acts as the effective support to provide abundant anchoring sites and heterogenous interfaces, which enable the catalyst to expose more active sites and accelerate charge transport. As a result, the representative IrO 2 @Co 3 O 4 -CoMoO 4 exhibits an outstanding OER activity ( η = 236 mV at 10 mA cm −2 ) with a superior mass activity of 713 A g –1 Ir at 1.53 V vs. RHE in 0.5 M H 2 SO 4 that are comparable to most reported catalysts. Theoretical calculations also reveal that the introduction of Mo can effectively modify electronic structure and decrease adsorption energy barriers of oxygen intermediates, and thereby enhancing OER catalytic activity. This work provides a new idea to develop highly efficient low Ir catalysts for OER.
研究领域:
材料科学
·
电化学
·
催化
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）