CHEMOSPHERE
·
2024
·
IF 8.1
Anlin Xu,Ziyan Yang,Zhiyi Zhou,Pu Yang,Yang Yu,Jiayang Liu,Yunhai Zhang
Hydrogen peroxide (H 2 O 2 ) synthesis by electrochemical two-electron oxygen reduction has garnered increasing interest as a wide range of potential applications. Gas diffusion electrodes (GDEs) can effectively promote the H 2 O 2 production efficiency by overcoming the oxygen mass transfer limitations but strongly influenced by the electrowetting process along the long-term operation. In this study, the effect of trans -electrode pressure (TEP) of GDE cathode on the electrowetting process was further elucidated. We controlled the TEP values of four types of GDEs: two Ni-based GDEs and two carbon cloth GDEs prepared by hot-pressing or brushing carbon black. SBA-15 was further used to regulate the microstructure of one Ni-based GDE. It was found that an optimal range of TEP occurred for all tested GDEs in terms of the max. concentration, the yield efficiency, the energy consumption, and the stability because TEP may change the triple-phase interface and influence the anti-electrowetting effect. The porosity of hot-pressed Ni GDE can maintain the TEP window and thus enhance the production of H 2 O 2 , likely via creating oxygen-containing functional groups and a bimodal pore structure on the electrode, revealed with several characterization techniques including SEM, CA, XPS , Raman spectra, CV and EIS . The porous Ni GDE presented an efficient and stable production of H 2 O 2 for 10 cycles: yielding H 2 O 2 at 4393.2–4602.2 mmol m −2 h −1 with current efficiencies of 94.2–98.7%. The best accumulated H 2 O 2 concentration can reach up to 3.58 ωt% H 2 O 2 at 10 h. The results provide an important reference for the industrial scaleup of electro-production of H 2 O 2 with GDEs.
研究领域:
电化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
ELECTROCHEMISTRY COMMUNICATIONS
·
2012
·
IF 4.859
Xiangheng Niu,Chen Chen,Hongli Zhao,Jie Tang,Yuxiu Li,Minbo Lan
A new screen-printed carbon electrode with porous architectures prepared using an extremely facile and low-cost approach is introduced. The preparation mainly involved a printing procedure of a graphite-based layer doped with CaCO 3 powders and a subsequent dissolution of these powders. The resulting porous screen-printed carbon electrode (P-SPCE) can offer large surface, broad potential window, low background current and high electrochemical reactivity. Moreover, the proposed P-SPCE provides enhanced performance for enzyme-free H 2 O 2 sensing compared to conventional glassy carbon electrodes and screen-printed carbon electrodes. These attractive properties of the P-SPCE are expected to be of wider applications.
研究领域:
生物化学
·
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Quanzhang Sun,Ming Gong,Ji Wang,Lifeng Chen,Wenlong Li,Yuezhou Wei
ABSRACT To extract lutetium (Lu) from LiCl-KCl fused salt, the electrode reaction mechanisms of Lu on W and liquid Zn electrodes were systematically investigated using a series of electrochemical methods such as cycle voltammetry (CV), square wave voltammetry (SWV), reverse chronopotentiometry (RCP), etc. The diffusion coefficient and diffusion activation energy of Lu(III) in LiCl-KCl fused salt were measured by CV. The results of CV, SWV and open circuit chronopotentiometry (OCP) confirmed that seven Lu-Zn intermetallic compounds were formed when Lu was deposited on Zn film electrode. Kinetic data of Lu(III)/Lu on W and liquid Zn electrodes, i.e., exchange current density, charge transfer resistance and reaction activation energy, were determined and compared by linear polarization (LP) at 773-848 K. Furthermore, the thermodynamic date such as equilibrium potential and formation Gibbs free energy of Lu-Zn alloys were also calculated and analyzed according to the OCP. The results demonstrate that the liquid Zn electrode is conducive to extract Lu from LiCl-KCl fused salt. Thus, constant potential electrolysis (CPE) was conducted at -1.58 V for 9 h on liquid Zn cathode to extract Lu from fused salt. The electrolytic product was composed of Zn and LuZn12 phases checked by XRD and SEM-EDS. The extraction rate of Lu is reached up to 98.37% based on the concentration change of Lu(III) in fused salt, which confirmed the feasibility to extract Lu employing liquid Zn electrode.
研究领域:
冶金学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
MEASUREMENT SCIENCE and TECHNOLOGY
·
2012
·Vol. 23
·期 12
·125101
·
IF 1.494
Hui Xu,Yiwen Pan,You Wang,Guang Li,Ying Chen,Ying Ye
The paper presents the design of an all-solid-state portable reference electrode based on a screen-printed carbon paste electrode suitable for rapid human serum testing. The electrode was covered by electropolymerized poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly(styrenesulfonate) (PSS) as an internal solid contact layer and polyvinyl chloride (PVC) membrane containing lipophilic anion and cation additives. The electrochemical properties of PEDOT(PSS) and PEDOT(PSS)/PVC film on a carbon paste electrode were studied by electrochemical impedance spectroscopy and cyclic voltammetry methods. The reference electrode exhibited good potential stability (for H+, Na+, K+, Ca2+, Cl− and CO2 −3/HCO−3), good reproducibility and long-term stability. The structure is applied as reference electrodes in human serum pH analysis with pH ion selective planar electrodes, forming a serum pH sensor. The response time of such a pH sensor was 15 s and the sensitivity was −52.2 ± 1.0 mV per decade. Other properties, such as repeatability, reproducibility and stability, were also evaluated. Clinical trials were carried out and compared with the results obtained from the routine hospital electrolyte analyzer, which demonstrated that their analytical performance was closely matched.
研究领域:
生物医学工程
·
电化学传感器
✓ 已验证
产品关联
DOI
高影响因子
MEASUREMENT SCIENCE and TECHNOLOGY
·
2013
·Vol. 24
·期 12
·125105
·
IF 1.435
Hui Xu,You Wang,Zhiyuan Luo,Yiwen Pan
An all-solid-state miniature calcium ion selective electrode (ISE) based on poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate) (PEDOT(PSS)) for continuous in situ measurement in seawater was studied. The electrode substrate was a platinum (Pt) wire of 0.5 mm diameter and PEDOT(PSS) was electropolymerized on one end of the Pt wire to act as the solid contact of this calcium ISE. The PEDOT(PSS) layer was covered with a calcium-selective poly(vinyl chloride) membrane, which contained ETH129 as calcium ionophore, potassium tetrakis-(p-chlorophenyl)borate as lipophilic anion and bis(2-ethylhexyl) sebacate as the plasticizer. Experiments using electrochemical impedance spectroscopy and reversed chronopotentiometry illustrated that electropolymerized PEDOT(PSS) decreased the resistance and improved the stability of the electrode. The sensors can work stably in the calcium ion concentration range of 10−6–10−1 mol L−1 with the slope of 27.7 mV/decade. Also Na+, K+ and Mg2+ can hardly interfere with the performance of the electrode. This electrode was applied to measure the calcium ion concentration of seawater samples. The experimental data showed that the electrode can resist the corrosion of seawater and its reproducibility was good (SD < 0.1 mM kg−1). The lifetime of such an electrode was at least six months. Because of the wire-shape and the small size of such a liquid junction free calcium electrode, it is pressure-resistant and easy to package and seal, therefore it is suitable for use in underwater equipment for in situ seawater measurement.
研究领域:
分析化学
·
海洋科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Xiaoqing Jiang,Jie Zou,Yongjian Ni,Yuheng Wang,Xianwei Qian,Xuebin Li,Shihao Wei,Yuanjie Su,Guangzhong Xie,Mingjun Zhou,Jiawen Jian
The catalytic activity of an oxygen-pumping electrode is very important to the performance of amperometric NO x (NO and NO 2 ) sensors. To enhance the stability of electrochemical NO x sensors based on Pt electrodes, we fabricated sensitive electrodes of Pt-based materials doped with small and different Au contents on 8% mol Y 2 O 3 -stabilized ZrO 2 (8YSZ) solid electrolyte substrates by screen printing and high-temperature co-firing. The effects of Au on the porous Pt electrode’s catalytic activity and long-term stability were investigated, and the results are as follows. First, the catalytic capacity of the Pt–Au alloy electrode decreases with increasing Au content due to the inhibition of the oxygen adsorption on Au, which decreases the amount of oxygen participating in the reaction at triple-phase boundaries (TPBs). Second, the catalytic ability of the alloy electrode decreases exponentially with aging time due to the reduction in the length of TPBs caused by the significant reduction in the number of holes in the electrode, and the oxidation of Pt. In addition, the conductivity decay rate of the electrode decreases with increasing Au doping. This indicates that Pt-based electrodes doped with varying Au contents, long-term, and high-temperature aging have notably regular effects on the catalytic activity of oxygen-pumping electrodes, for which we have developed a model of Au passivation and the synergistic effect of aging time on the activity of Pt-based oxygen-pumping electrodes.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 46
·26718-26728
·
IF 3.049
Wei Han,Wenlong Li,Jiazhuang Chen,Mei Li,Zhuyao Li,Yongchang Dong,Milin Zhang
Cyclic voltammetry, square wave voltammetry, linear polarization, chronopotentiometry and chronoamperometry were performed to investigate the electrochemical properties of Y(III) on W and Pb electrodes in LiCl–KCl eutectic melts. The diffusion coefficient of Y(III) measured by various techniques was in the order of 10−5. The nucleation of Y on W electrode was found to comply with the instantaneous nucleation mechanism. With increasing temperature, the exchange current densities increased and the charge-transfer resistances decreased, and exchange current densities are distinctly larger on liquid Pb electrode compared with W electrode. In addition, the co-deposition mechanism of Y(III) and Pb(II) on W electrode was also studied and four Pb–Y intermetallics could be detected. The feasibility of extraction metallic Y from the melts was explored by co-deposition on W electrode and under-potential deposition on liquid Pb electrode and the extracted products consisted of Pb3Y and Pb phases.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Wan Wang,Hua Bai,Haiyu Li,Qing Lv,Qing Zhang,Ning Bao
Fabrication of disposable gold working electrodes in bulk is desirable for their extensive application in electrochemical detection . In this paper the gold film electrodes were prepared by sputtering the gold film with the thickness of ∼12 nm on the double sided conductive carbon tape. The gold film coated carbon tape could be used like stickers with small square pieces and attached on ITO glass for fabrication of disposable gold film electrodes. The electrochemical responses of the gold film modified electrodes on Cr(VI) in acidic solutions were similar to previous gold electrodes, suggesting the similar mechanism as before. Cr(VI) could be determined by the amperometric method with the detection limit of 0.7 μg L −1 (0.013 μM), which was significantly improved compared with previously reported disposable gold-based electrodes. The batch-by-batch (n = 20) reproducibility of the fabricated electrodes was 7.3% at 50 μg L −1 and 3.8% at 5.0 mg L −1 , respectively. The disposable electrodes could be applied to quantify Cr(VI) in real samples including plastics, tap water and lake water with results in agreement with those obtained with HPLC-ICP-MS. This study provides a simple and effective alternative for preparation of disposable gold film electrodes.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2020
·
IF 12.35
Peikun Zhang,Wei Wang,Hui Wang,Yanbo Li,Chunhua Cui
Although much is known about the increased rate of a catalyst required for the oxygen evolution reaction (OER), the hole accumulation behaviors of the catalyst on both photo- and dark electrodes remain uncovered. We present a rational tuning of the hole-accumulation and hole-transfer ability of a catalyst by in situ deposition of IrOx on NiOx islands on model Si electrodes and we demonstrate a distinct hole accumulation behavior during the OER through electrochemical methods, in situ UV–vis and Raman spectroelectrochemistry. We find that the NiOx islands with <10% coverage on an n++-Si dark electrode demonstrate a 6-fold higher capacity of hole accumulation relative to that on an n-Si photoanode under illumination. A further in situ targeted deposition of soluble hexahydroxyiridate on the NiOx leads to the formation of NiOx/IrOx junctions, where the IrOx further depletes the extracted holes by NiOx from the n-Si photoanode decreasing the overpotential by ∼260 mV at 20 mA cm–2, yet the IrOx promotes the hole accumulation at the NiOx/IrOx on the dark electrodes presenting a similar decrease of the overpotential. In contrast to the dark-holes, an extremely lower charging level of photogenerated holes of the same catalyst at the identical current density reasoned a seemingly higher reactivity to drive the OER, and reasonably demonstrated a stronger oxidation/corrosion to the Si electrode.
研究领域:
电化学
·
材料科学
·
催化
·
可再生能源
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2015
·
IF 3.091
Yapeng He,Weimin Huang,Rongling Chen,Wenli Zhang,Haibo Lin,Hongdong Li
The electrochemical abatement of aspirin, a representative anti-inflammatory drug, is carried out through anodic oxidation by employing PbO 2 , boron-doped diamond (BDD) and porous Ti/BDD as anodes. The effect of nature characteristic and structure of the electrode material on the electrochemical oxidation is systematic investigated. The redox behavior of aspirin on different electrodes is studied by linear sweep voltammetry. Completely mineralization of aspirin could be achieved on BDD electrodes. The results show that the electrochemical incineration of aspirin on three electrodes follows a pseudo first-order kinetics behavior with apparent rate constant of 0.051, 0.185 and 0.367 h −1 for PbO 2 , flat BDD and porous BDD electrode. Electrochemical degradation mechanism on BDD electrodes involves the direct and indirect electrochemical oxidation while there is only indirect oxidation for aspirin on PbO 2 electrode. Porous Ti/BDD presents the best excellent electrochemical oxidation ability for aspirin compared with flat BDD and PbO 2 electrode. The discrepancy of electrochemical oxidation could be explained in terms of in situ generation and utilization rate of hydroxyl radicals on the surface of electrode materials.
研究领域:
环境科学
·
电化学
·
药物降解
✓ 已验证
产品关联
DOI
高影响因子
Batteries & Supercaps
·
2024
·
IF 5.1
Veronika Zahorodna,Denys S. Butenko,Iryna Roslyk,Ivan Baginskyi,Volodymyr Izotov,Oleksiy Gogotsi
Graphical The proposed mathematical model is developed for the carbon supercapacitor in organic electrolyte, establishing a relationship between the specific capacitance of a device, the thickness of its electrodes and the weight of its passive components. Such model enables optimization of the electrode thickness, thus maximizing specific energy density for a chosen carbon electrode material. Increasing energy density without sacrificing the lifetime, power and cyclability of electrochemical capacitors is a very important goal. However, most efforts are directed toward the improvement of active charge-storing materials, while the design of devices and minimization of the weight/volume of the passive component have received less attention. We propose here a mathematical model of a carbon supercapacitor in organic electrolyte, which establishes a relationship between the specific capacitance of a device, the thickness of its electrodes, and the weight of its passive components (case, external current leads, current collectors, etc.). The model was built based on experimentally obtained dependences and has been validated using experiments with electrodes made of two porous carbon materials. Regardless of the pore size distribution in the specified range of electrode thicknesses, the functional dependence of the electrode's specific capacitance on the thickness is well described within the linear approximation. The developed model enables optimization of the electrode thickness, thus maximizing specific energy density for a chosen carbon electrode material.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 20
·期 2
·2305639
·
IF 13.3
Shiwei Xu,Qiu Fang,Jipeng Wu,Suting Weng,Xiaoyun Li,Qiuyan Liu,Qiyu Wang,Xiqian Yu,Liquan Chen,Yejing Li,Zhaoxiang Wang,Xuefeng Wang
Prelithiation is an essential technology to compensate for the initial lithium loss of lithium-ion batteries due to the formation of solid electrolyte interphase (SEI) and irreversible structure change. However, the prelithiated materials/electrodes become more reactive with air and electrolyte resulting in unwanted side reactions and contaminations, which makes it difficult for the practical application of prelithiation technology. To address this problem, herein, interphase engineering through a simple solution treatment after chemical prelithiation is proposed to protect the prelithiated electrode. The used solutions are carefully selected, and the composition and nanostructure of the as-formed artificial SEIs are revealed by cryogenic electron microscopy and X-ray photoelectron spectroscopy. The electrochemical evaluation demonstrates the unique merits of this artificial SEI, especially for the fluorinated interphase, which not only enhances the interfacial ion transport but also increases the tolerance of the prelithiated electrode to the air. The treated graphite electrode shows an initial Coulombic efficiency of 129.4%, a high capacity of 170 mAh g −1 at 3 C, and negligible capacity decay after 200 cycles at 1 C. These findings not only provide a facile, universal, and controllable method to construct an artificial SEI but also enlighten the upgrade of battery fabrication and the alternative use of advanced electrolytes.
研究领域:
材料科学
·
电化学
·
电池技术
✓ 已验证
DOI
高影响因子