ChemSusChem
·
2021
·Vol. 15
·期 4
·e202102049
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IF 8.928
Pingping Huang,Tingting Fan,Xintao Ma,Jiguang Zhang,Yanping Zhang,Zhou Chen,Xiaodong Yi
Graphical Lowering barriers : Bimetallic ZnCo 2 O 4 catalyst can promote nitrate electroreduction at room temperature. The electron-deficient Co active site can lower the energy barriers for the formation of *NO 2 intermediate and suppress the hydrogen evolution reaction, thus enhancing the selectivity and yield rate of electrochemical NO 3 − reduction to ammonia. Nitrate (NO 3 − ) as a common pollutant of groundwater causes drinking water safety problems and seriously endangers people‘s health. Electrochemical reduction of nitrate to ammonia under ambient condition is a green and significant route to reduce the concentration of NO 3 − and produce ammonia (NH 3 ), known as a complement to the Haber–Bosch reaction. Currently, noble-metal electrocatalysts are often used in electrochemical reduction of NO 3 − , but high cost and scarcity limited their application. Herein, three-dimensional (3D) flower-like zinc cobaltite (ZnCo 2 O 4 ) electrocatalyst was developed to convert nitrate into ammonia at room temperature. The NH 3 yield rate could reach up to around 2100 μg mg −1 h −1 at a potential of −0.6 V vs. reversible hydrogen electrode (RHE), which was around 2.0 times higher than that of pristine Co 3 O 4 . In addition, the NH 3 faradaic efficiency of ZnCo 2 O 4 electrocatalyst could reach around 95.4 % at potential of −0.4 V vs. RHE with good structural and morphological stability, which surpassed most reported non-noble metal-based electrocatalysts. Further studies concluded that the improved activity of electrocatalytic NO 3 − reduction was ascribed to the existence of abundant active sites and the charge transfer from Co atoms to Zn atoms after Zn doping. Importantly, this work opens a new path for the development of Co-based materials as electrocatalysts for reducing nitrate to ammonia.
研究领域:
环境科学
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电化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 72
·44551-44570
·
IF 3.119
Yirui Shu,Pan Zhang,Yanjun Zhong,Xiangyang Xu,Genkuan Ren,Wei Wang,Hengli Xiang,Zhiye Zhang,Xiushan Yang,Xinlong Wang
A new low-cost composite of ZnCoxFe2−xO4 loaded on rice hull carbon (ZnCoxFe2−xO4-RHC) was synthesized via waste ferrous sulfate (the industrial waste produced in the process of producing titanium dioxide) and rice hull as raw materials, which was applied for the degradation of bisphenol A (BPA) by heterogeneous activated peroxodisulfate (PS). A series of characterizations including XRD, SEM, FTIR, and BET analysis were carried out to analyze the structure and morphology of the materials. It is confirmed that the ZnCoxFe2−xO4-RHC composites show better catalytic activity and performance than other control samples, which can be attributed to the synergistic effect of Fe and Co, ZnCoxFe2−xO4 and RHC based on these analyses. The degradation rate of BPA by ZnCo1.3Fe0.7O4-50%RHC reached 100% within 15 min, and it can still maintain good catalytic efficiency after 5 cycles. ESR test and XPS results showed that free radical and non-free radical processes were involved in BPA degradation. These findings offer a novel, low cost and simple strategy for rational design and modulation of catalysts for the industrial degradation of organic pollutants, and provide a new idea for the utilization of waste ferrous sulphate in titanium dioxide industry.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
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2021
·
IF 9.127
Caixia Liu,Zhe Zhao,Yang Liu,Qingshan Lu
Hierarchical and binder-free electrode materials with large electroactive sites and low contact resistance are benefit for electrochemical capacitors . Herein, this paper reports the binder-free and hierarchical ZnCo 2 O 4 arrays decorated with carbon dots (CDs/ZnCo 2 O 4 ) on nickel foam by hydrothermal route. The CDs/ZnCo 2 O 4 arrays exhibit the nanowires-assembled hierarchical grass-like structure. The outward directed nanowires yield high surface-to-volume ratio. The nanowires exhibit the average length of 1 μm and diameter of 50 nm. The specific capacitance of the CDs/ZnCo 2 O 4 can reach 1937 F/g higher than the 1192 F/g of bare ZnCo 2 O 4 at 1 A/g. And 78.5% capacitance retention rate is achieved while the current density increases from 0.5 to 8 A/g. 90% of the capacitance retention over 5000 charge-discharge cycles at 15 A/g indicates high cycling stability. These boosted electrochemical performances are attributed to the structural feature with exposed electroactive sites, high electrical conductivity assisted by CDs, and opened interspaces for electrolyte ion diffusion. Asymmetric two-electrode system assembled with CDs/ZnCo 2 O 4 and activated carbon delivers a high-energy density of 54.94 W h/kg at 425.3 W/kg and retains an energy density of 13.23 W h/kg at 6804 W/kg. This study provides a new approach to design high-performance electrode materials for supercapacitors.
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
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Qi Feng,Yanbing Sun,Huimin He,Jing Zhao,Fanyuan Meng,FuXing Wang,Dezhou Zheng,Guangxia Wang,Fuqin Deng,Ningbo Yi,Bingjun Jin
Exploring cost-effective and high-performance electrocatalysts for oxygen evolution reaction (OER) is quite significant for utilizing renewable energies by converting them to green hydrogen energy. ZnCo 2 O 4 spinel oxide has drawn a wide attention in water electrolysis field owing to its earth abundance, low cost and eminent electrocatalytic activity. However, it still has a great room to boost its OER catalytic activity due to the low electrical conductivity and restricted active sites of ZnCo 2 O 4 catalyst. Herein, a facile, easy-scalable and environmental-friendly quenching method is exhibited to achieve surface Fe doped and oxygen vacancy generated ZnCo 2 O 4 by instantaneous cooling in Fe(NO 3 ) 3 solution. As a result, the quenched ZnCo 2 O 4 catalyst shows a vastly improved OER activity in alkaline electrolyte, only requiring an overpotential of 332 mV to reach 10 mA cm −2 , which is much lower than that of un-quenched ZnCo 2 O 4 (405 mV). Our results manifest that quenching treatment can endow an active Fe amorphous layer, a higher ratio of Co 3+ states and more abundance oxygen vacancies for ZnCo 2 O 4 spinel oxide, thus possessing a higher OER activity. Our work offers an effective path for the regulation of metal oxides and its application in energy catalysis field.
研究领域:
材料科学
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能源催化
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Mengshu Li,Ziquan Zeng,Weicai Liu,Hui Zong,Bo Li,Shijing Gong,Ke Yu,Ziqiang Zhu
In space, electrolysis of water is one of the main methods to generate oxygen (for life support), and its harsh environment places higher demands on the oxygen evolution reaction (OER). Cobalt-based carbonate hydroxides (CCH) have emerged as new candidates for OER catalysts in recent years. However, disadvantages such as poor catalytic activity and easy agglomeration of pristine CCH hinder its application in catalysis. Herein, we synthesized ZnCoCH@Ti 3 C 2 T x heterostructure with a unique structure of grass-like Zn-doped bimetallic carbonate hydroxides grown in situ on MXene by a solvothermal method. The ZnCoCH@Ti 3 C 2 T x electrocatalyst in 1 M KOH shows a low overpotential (280 mV) at 10 mA cm −2 , a small Tafel slope (46.2 mV dec -1 ) and a Faraday efficiency of nearly 100 %. The experimental and DFT calculations show that MXene plays a dual enhancing role as a conductive carrier and a reducing agent in improving the OER performance. As a conductive carrier, MXene alleviates the agglomeration of ZnCoCH and enhances the conductivity and charge transfer ability of the heterostructure. As a reducing agent, MXene provides more redox sites by reducing ZnCoCH and promotes the adsorption of intermediate species on the catalyst. Zn is not only an economical and eco-friendly metal but also may have anti-toxicity. This study provides a reasonable idea for the design of efficient, economical, green and poison-resistant OER catalysts for electrolytic water.
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
CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Xing Zhang,Xiurong Yang,Suhang Chen,Shuai Dong,Enzhou Liu,Hui Li,Haixia Ma,Kangzhen Xu
The rational regulation of electron transfer between Co-based catalysts and peroxymonosulfate (PMS) plays a key role in the photo-Fenton catalytic oxidation process. In this study, a novel Eu-doped ZnCo 2 O 4 composite was successfully prepared via a simple hydrothermal calcination method, and firstly used for PMS activation to degrade 1,1-diamino-2,2-dinitroethene (FOX-7). Among all samples, Eu 0.4 -ZnCo 2 O 4 exhibited remarkable PMS activation performance, which was about 5.67 times higher than that of undoped ZnCo 2 O 4 . The enhanced catalytic performance could be attributed to the generation of abundant oxygen vacancies (OVs), which greatly promoted the separation of carriers and accelerated the cycling of the Co 3+ /Co 2+ redox pairs. The corresponding Co 3+ /Co 2+ and oxygen defects/lattice oxygen (O Def /O Lat ) ratios regulated catalytic-activity relationship were successfully established by regression analysis. Radical quenching tests and electron paramagnetic resonance (EPR) revealed that non-radical pathway dominated the degradation process, and singlet oxygen ( 1 O 2 ) was the main active species. Importantly, theoretical calculations demonstrated that the synergy of doping and OVs could effectively improve adsorption energy and enhance electron transfer for promoting the activation of PMS. This study offers a deep insight into the catalytic reaction mechanism and provides a new strategy for developing heterogeneous photocatalysts in activating PMS for environmental remediation.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Jianhui Feng,Hu Zhou,Danyang Chen,Ting Bian,Aihua Yuan
The electrocatalysts with high activity and low cost are essential for hydrogen evolution reaction (HER). Herein, we report an approach to prepare hierarchical core-shell structures Zn x Co 1-x /NC@MoS 2 . The Zn/Co ratio affects the particle sizes of Zn x Co 1-x /NC polyhedra and the distribution of Co nanoparticles , resulting in the change of the amount of exposed active sites and further afforded tunable HER activities. Notably, the hybrids exhibit significantly superior catalytic activities to pristine MoS 2 . The optimal catalyst displays an extraordinary HER performance in acid media with a low overpotential of 130 mV at 10 mA cm −2 and high durability. The remarkable HER properties mainly originate from the fantastic structural characteristics such as abundant exposure of MoS 2 edge-sites, uniform distribution of Co-N x species, as well as the porousness and high conductivity of supports. This research provides a promising strategy to develop inexpensive and highly-efficient HER electrocatalysts derived from metal-organic frameworks and MoS 2 .
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
·
IF 9.965
Jingchen Luo,Xinyi Zhou,Yingxia Dong,Na Jiang,Qiaoji Zheng,Dunmin Lin
Transition-metal sulfides boast a high theoretical capacity and have been regarded as a kind of prospective electrodes for supercapacitors; nevertheless, their inherent poor conductivity and low electrochemical active sites limit the practical applications of the materials. Herein, flower-like zinc cobalt sulfide (ZCS) microspheres with rich sulfur vacancies (ZCS δ ) have been synthesized by a three-step procedure of hydrothermal, post-annealing and room-temperature sulfuration treatments. The flower-like microspheres self-assembled by ultrathin nanosheets bring the active material fully contact with electrolyte, facilitating ion diffusion during charging and discharging. Furthermore, defect engineering of sulfur vacancies at the atomic level raises the intrinsic conductivity and increases active sites for electrochemical reactions. As a result, the obtained sulfur-deficient ZCS microspheres possess an excellent specific capacitance of 2709 F g −1 at 1 A g −1 and an exceptional cycling lifespan of maintaining 90.9% of the initial capacitance over 3000 cycles. In addition, the hybrid supercapacitor employing (HSC) sulfur-deficient flower-like ZCS microspheres as the positive electrode present a high energy density of 28 Wh kg −1 at the power density of 800 W kg −1 . This investigation proposes an efficient strategy to significantly and synergistically enhance the electrochemical performance of the electrodes for hybrid supercapacitor by the comprehensive engineering of defect and morphology.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2025
·
IF 3.9
Xingtang Xu,Guang Sun,Xueling Wang,Yanwei Li,Jianliang Cao,Yan Wang,Hari Bala
Recently, the detection of acetone by using a gas sensor fabricated with metal oxide semiconductors has stimulated intense research enthusiasm, owing to its promising application in the noninvasive diagnosis of diabetes by monitoring human exhaled breath. In this work, a potential acetone sensor was fabricated by comodification of the nanosheets-assembled ZnCo2O4 hierarchical microspheres (HMSs) with MoO3 and Ag nanoparticles (NPs). The ZnCo2O4 HMSs were synthesized via a solvothermal route and then sequentially modified with MoO3 and Ag NPs via immersion, calcination, and photoreduction routes. The results of gas sensing measurement indicated that after modification with MoO3 and Ag, a continuous improvement of acetone sensitivity was realized on the ZnCo2O4 sensor. At the optimal working temperature of 260 °C, the response of the best Ag/MoO3/ZnCo2O4 sensor to 50 ppm of acetone was 7.23, which was about 3.3 and 1.4 times higher than that of ZnCo2O4 and MoO3/ZnCo2O4, respectively. Apart from the higher response, the selectivity and response speed of the Ag/MoO3/ZnCo2O4 sensor were also improved. The results of density functional theory calculations showed that the enhanced absorbability of ZnCo2O4 for acetone after modification with MoO3 and Ag should be responsible for the improved acetone sensitivity and selectivity of the Ag/MoO3/ZnCo2O4 sensor.
研究领域:
材料科学
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医学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2025
·
IF 2.5
Xiao Linfeng,Wang Xinyue,Fu Lichun,Deng Wenqiang,Liang Boyu,Li Runrun,Hong Yan,Du Jie,Zhou Zhenyuan,Liao Runhua
Due to the low cost and abundant reserves of transition metals, there is an urgent imperative for the design and fabrication of transition metal electrocatalysts to expedite hydrogen production through the hydrogen evolution reaction (HER). We present a self-supported needle-grass-shaped Zn-Co (ZC) composition on porous nickel foam (NF) via conventional hydrothermal synthesis. The Zn-Co/NF electrodes demonstrate remarkably efficient HER performance in 1.0M KOH alkaline solution. Specifically, the ZC (1:4)/NF catalyst exhibits an overpotential of 171.9 mV at a current density of 10 mA cm −2 owing to the synergistic effect arising from the combination of Zn-Co composition and Ni layers. Furthermore, stability tests demonstrate that the linear sweep voltammetry (LSV) curves of the ZC (1:4)/NF catalyst exhibits only marginal changes even after undergoing 1000 consecutive cycles at a scan rate of 20 mV s −1 . This study presents an innovative approach for the design and fabrication of highly efficient electrocatalysts for HER. Graphical
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Le Xu,Yukun Xi,Xiaojun Sun,Pusu Zhao,Fengxia Zhu,Jingzhou Yin,Luyang Chen,Junhua Hu,Xifei Li
Rational design of the electrode materials in distinctive architecture and tailored composition is critical for regulating their electrochemical properties . Herein, the novel porous zinc-cobalt sulfides (ZCS) bead-curtain-like arrays (BCA) supported by three-dimensional Ni foam (NF) (denoted as ZCS/NF BCA) are fabricated as advanced electrode for supercapacitors (SCs), which exhibit remarkable electrochemical performances in respect of superb capacity of ~837 C g −1 (specific capacitance of ~1860 F g −1 ) at 1 A g −1 and ultra-long cycling stability (~92.9% retention after 5000 cycles at 6 A g −1 ). Furthermore, the assembled hybrid supercapacitors based on ZCS/NF BCA delivers ultrahigh energy density of ~88 Wh kg −1 with a maximum power density of ~800 W kg −1 . The excellent properties may be ascribed to the combined contributions from the hierarchical bead-curtain architecture of ZCS/NF BCA composite and the bimetallic sulfide with abundant valence states for rich redox reactions .
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2015
·
IF 4.504
Yanhui Liang,Qian Liu,Yonglan Luo,Xuping Sun,Yuquan He,Abdullah M. Asiri
In this paper, we report the use of Zn 0.76 Co 0.24 S/CoS 2 nanowires array on Ti mesh (Zn-Co-S/TM) topotactically derived from ZnCo 2 O 4 nanowires array precursor as a durable and efficient bifunctional hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalyst in strongly alkaline media. This Zn-Co-S/TM electrode drives 20 mA cm −2 at 238 mV HER overpotential and 20 mA cm −2 at 330 mV OER overpotential. The corresponding two-electrode alkaline water-splitting system achieves 10 mA cm −2 at a cell voltage of 1.66 V.
研究领域:
材料科学
·
电化学
✓ 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）