Chem Catalysis
·
2023
·
IF 9.4
Mengxuan Li,Wenwen Xu,Daojin Zhou,Yuyan Zhang,Yun Kuang,Hai Liu,Xingdong Wang,Yang Zhong,Zhongbin Zhuang,Hui Li,Liang Luo,Xiaoming Sun
Electrocatalytic gas consumption reactions (EGCRs), such as the oxygen reduction reaction (ORR) in fuel cells, are important half-cell reactions in electrochemical devices. The reactivity of active sites and gas diffusion kinetics are key to the performance of EGCRs; however, conventional characterization techniques can hardly give an accurate evaluation of the gas diffusion property and the structure features of gas diffusion electrodes (GDEs) under practical electrochemical working conditions. Here, we evolve a simple bubble pump consumption chronoamperometry (BPCC) method to evaluate the gas diffusion property of GDEs with ORR as a probe reaction via the real-time electrochemical response of a single-bubble injection. Two key parameters of GDE, diffusion coefficient and effective catalytic sites, can be extracted from the fitted diffusion-controlled reaction equation. Measurements of various GDEs under different working conditions demonstrate high accuracy and reliability of the BPCC method, making it a facile and promising evaluation standard for characterizing GDEs.
研究领域:
电化学
·
材料科学
·
能量转换
·
催化
✓ 已验证
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2022
·
IF 4.969
Zhiwei Wang,Mingqiang Cheng,Jiaojiao Bu,Lei Cheng,Juanjian Ru,Yixin Hua,Ding Wang
Tin is one of the vital substances in the material and chemical industry. Deep eutectic solvent (DES) possesses excellent physicochemical properties for metal preparation. In this study, the electrochemical behavior of Sn(II) and metallic tin preparation in choline chloride-ethylene glycol (ChCl-EG) DES were investigated. Linear sweep voltammetry is carried out to study the effects of substrate material (Ni, Cu, Pt, C, Fe, Al, W, glassy carbon (GC) and Ti), temperature (313–353 K) and SnCl 2 concentration (10–100 mM) on the electrochemical behavior of Sn(II)/Sn. Results demonstrate that metallic tin is easier to be prepared on the Ni electrode, and increasing temperature and SnCl 2 concentration both facilitate the reduction of Sn(II). Electrospray ionization mass spectrometry (ESI-MS) shows that the main form of Sn(II) is [SnCl 3 ] - . Chronoamperometric tests indicate that with the increase of applied potential, the nucleation of Sn(II) on the nickel electrode becomes close to the instantaneous nucleation. Simultaneously, the nucleation rate and the number of active sites on the electrode surface increase significantly. Pure tin with a dendritic structure could be prepared with higher current efficiency of 96.4% and lower energy consumption of 320.5 kW·h·t −1 without any additives. All these studies provide a fundamental basis for the preparation of tin powders in ChCl-EG DES.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Coatings
·
2020
·Vol. 10
·期 12
·1154
·
IF 2.436
Xiaozhou Cao,Lulu Xu,Chao Wang,Siyi Li,Dong Wu,Yuanyuan Shi,Fengguo Liu,Xiangxin Xue
The electrochemical behavior and electrodeposition of Sn were investigated in choline chloride (ChCl)–urea deep eutectic solvents (DESs) containing SnCl2by cyclic voltammetry (CV) and chronoamperometry techniques. The electrodeposition of Sn(II) was a quasi-reversible, single-step two-electron-transfer process. The average transfer coefficient and diffusion coefficient of 0.2 M Sn(II) in ChCl–urea at 323 K were 0.29 and 1.35 × 10−9cm2∙s−1. The nucleation overpotential decreased with the increase in temperature and SnCl2concentration. The results of the chronoamperometry indicated that the Sn deposition on tungsten electrode occurred by three-dimensional instantaneous nucleation and diffusion controlled growth using the Scharifker–Hills model. Scanning electron microscopy (SEM) showed that the morphology of the deposits is uniform, as a dense and compact film prepared by potentiostatic electrolysis on Cu substrate. X-ray diffraction (XRD) analysis revealed that the deposits were pure metallic Sn.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED ELECTROCHEMISTRY
·
2022
·Vol. 53
·期 4
·847-860
·
IF 2.925
Liu Zuowei,Guo Xueyi,Tian Qinghua,Xu Zhipeng
Abstract The gallium electrowinning process is always accompanied by hydrogen evolution reaction that results in low current efficiency (CE). In this manuscript, cyclic voltammetry and chronoamperometry studies were carried out to investigate the gallium cathode behavior under various conditions and explore the parameter that is beneficial to improve the CE. The CE of the lead and copper cathodes was higher, while gallium deposited on the titanium, SUS316, and SUS304 cathodes was readily separated. Increasing the overpotential and gallium concentration or decreasing the pH within a certain range was all beneficial to improve the CE, while the temperature had no significant effect on the CE. Kinetic studies of gallium electrodeposition were carried out. The gallium electrodeposition process was determined as mixed control and forced convection is expected to further improve the CE. The apparent activation energy and kinetic current from the electrochemical reactions were determined to be 23.335 kJ mol −1 and 47.6 mA, respectively. Graphical abstract
研究领域:
电化学
·
材料科学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Xiaozhou Cao,Lulu Xu,Yuanyuan Shi,Yaowu Wang,Xiangxin Xue
The electrochemical behavior and electrodeposition of cobalt was investigated in the choline chloride-urea deep eutectic solvent containing cobalt chloride. Cyclic voltammetry was used to study the effect of temperature and concentration on the electrochemical behavior of cobalt. Chronoamperometry results show that as the applied potential increases, the electrocrystallization of cobalt on the tungsten electrode gradually tends to three-dimensional instantaneous nucleation. SEM observation of the microstructure of the coating shows that the deposited films obtained in this experimental condition (−0.85 V ∼ −1.0 V; 343 K–373 K) are dense and uniform with fine crystals. As the deposition potential increases, the contours of the particles are become clear and the edges of the particles gradually join. As the temperature rises, the coating particles increase to become gradually uniform, the plush contour gradually disappears, and the particles are no longer connected with the other particles. EDS and XRD analyses show that pure cobalt coating was obtained.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
MEASUREMENT SCIENCE and TECHNOLOGY
·
2024
·Vol. 36
·期 1
·015903
·
IF 2.7
Qingqing Wang,Yu Pan,Yanyan Wang,Kaikai Zhang,Shengzhe Shi,Sheng Liu
Traditional electrochemical workstations are costly, complex, bulky, and primarily used in laboratories. This study develops a reliable, practical, and cost-effective portable wireless potentiostat to achieve real-time detection on-site and overcome the limitations of traditional electrochemical workstations. The system employs a general-purpose microcontroller unit, a dual-mode bluetooth module and cost-effective multi-analog-to-digital converter to achieve differential sampling of the LMP91000. The system is equipped with buttons and OLEDs, enabling connection to mobile phones and computers for in-depth data analysis or independent operation. The system was successfully tested with [Fe(CN)6]3−, C6H12O6, and C3H6O3 solutions at concentrations ranging from 0 to 20 mm. The goodness-of-fit (R2) values are 0.984, 0.996, and 0.998, respectively. The average relative standard deviation of the three blank solutions is approximately 3.22%. The detection limits measured (0.003, 0.009, and 0.005 mm) are all lower than the minimum detection concentration (0.2, 0.1, and 0.1 mM). The coefficient of variation for repetitive experiments is less than 5.53%. The device accurately executed chronoamperometry (applied voltage range is ± 1.2 V, current range is ± 882 μA, accuracy is ±1%) with high sensitivity and good repeatability. Based on this circuit, a lactic acid detector and a urine glucose detector were developed, which work stably and support long-term operation, proving the stability and reliability of the circuit. Compared to commercial electrochemical workstations, portable wireless electrochemical system offers remarkable advantages in cost (<$6.4), size (41.5 mm × 76.5 mm), and practicality, making it suitable for a range of applications, including biomedical analysis, food safety, environmental monitoring, and smart wearables.
研究领域:
生物医学工程
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2026
·
IF 5.2
Junying Peng,Shengjie Lu,Nan Su,Wenbei Situ,Xianliang Song
Caffeine, a central nervous system stimulant ubiquitously present in many plants such as coffee and tea, is conventionally quantified using chromatographic and electrophoretic techniques. Despite the advantages of rapid response, simple instrumentation, and low cost, photoelectrochemical (PEC) sensing remains underdeveloped for caffeine analysis. In this study, a novel PEC sensor was constructed by integrating BiVO 4 nanoparticles with Co-TCPP MOF on ITO (BiVO 4 /Co-TCPP MOF/ITO), with the aim of caffeine detection. A series of structural, morphological, optical and photoelectrochemical analyses were conducted on the BiVO 4 /Co-TCPP MOF/ITO electrode. The results demonstrated that the incorporation of Co-TCPP MOF significantly enhanced the photoelectrochemical performance of the material attributable to their extensive π-conjugated system, achieving a photocurrent density of 2.01 mA/cm 2 at 0.6 V (vs. Ag/AgCl), approximately 3.3-fold higher than pristine BiVO 4 (0.59 mA/cm 2 ). After optimization of key parameters including Co-TCPP MOF dosage, electrolyte, applied bias, the sensor exhibited a robust linear response to caffeine in the range of 0.5–120 μM, with a detection limit of 0.12 μM. Moreover, it displayed excellent selectivity, reproducibility (RSD < 3.5%), and long-term operational stability. Application to real tea and coffee samples achieved satisfactory recoveries (95.8–103.2%), with results consistent with HPLC-MS/MS, confirming its reliability. This work provides an efficient PEC caffeine sensing platform and new insights for designing MOF-semiconductor hybrids for advanced optoelectronic sensing.
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Jing Meng,Moustafa Zahran,Ahmed S. Abou-Elyazed,Xiaolin Li
Herein, we report a novel electrochemical sensor for determining glucose in sweat, employing a graphene/metal–organic framework (MOF) as a modifier for stainless steel (SS) electrode. The MOF structures, MIL-101(Cr), MIL-101(Cr)-NO 2 , and MIL-101(Cr)-NH 2 , were hydrothermally synthesized and then characterized using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, N 2 adsorption/desorption isotherms, and scanning electron microscopy (SEM). XRD and SEM results proved the formation of the crystalline MIL-101(Cr) and MIL-101(Cr)-NO 2 , and the amorphous MIL-101(Cr)-NH 2 . Additionally, FT-IR and isotherms confirmed their composition and mesoporosity, respectively. The amorphous MIL-101(Cr)-NH 2 showed the best electrocatalytic activity towards glucose oxidation among the fabricated MOFs. The electrocatalytic activity was also boosted after incorporating conductive graphene. Under optimized conditions, graphene/MIL-101(Cr)-NH 2 /SS was used for glucose determination using square wave voltammetry and chronoamperometry with detection limits of 0.004 and 0.01 mM, respectively. Moreover, the modified electrode showed acceptable recovery values when it was applied to detect glucose in artificial sweat samples.
研究领域:
材料科学
·
生物医学工程
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Rong Wang,Yi Xu,Chunyan Wang,Huazhou Zhao,Renjie Wang,Xin Liao,Li Chen,Gang Chen
A novel composite structure of reduced graphene oxide (rGO)–Ag nanoparticles (Ag NPs) nanocomposite, which was integrated on the indium tin oxide (ITO) glass by a facile and rapid two-step chronoamperometry electrodeposition route, was proposed and developed in this paper. SERS-activity of the rGO/Ag NPs nanocomposite was mainly affected by the structure and size of the fabricated rGO/Ag NPs nanocomposite. In the experiments, the operational conditions of electrodeposition process were studied in details. The electrodeposited time was the important controllable factor, which decided the particle size and surface coverage of the deposited Ag NPs on ITO glass. Under the optimized conditions, the detection limit for rhodamine6G (R6G) was as low as 10 −11 M and the Raman enhancement factor was as large as 5.9 × 10 8 , which was 24 times higher than that for the ITO–Ag NPs substrate. Apart from this higher enhancement effect, it was also illustrated that extremely good uniformity and reproducibility with low standard deviation could be obtained by the prepared ITO-rGO/Ag NPs nanocomposite for SRES detection.
研究领域:
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2015
·
IF 6.409
Yanxue Xu,Lei Zhang,Yuan Liu,Zhaoyu Jin,Qian Zhao,Feng Yang,Dan Xiao
Electrochemiluminescence (ECL) material Ru-dpq (Ru(bpy) 2 dpq 2+ , dpq=1,10-phenanthroline-5,6-dione; bpy=2,2′-bipyridine) is found to be produced strong and stable anodic ECL signal, which could be quenched by reduced glutathione (GSH) and exhibits high sensitivity and selectivity simultaneously. According to the mass spectra of Ru-SG (product of Ru-dpq reacted with GSH), and single crystal structure of the final oxidized product Ru-dcbpy ((Ru(bpy) 2 dcbpy 2+ , dcbpy=3,3-dicarboxy-2,2-bipyridine), we propose a new interacted mechanism between Ru-dpq and GSH. A good linear relation is estimated to be from 0.1 pM to 50 μM in the presence of calcium ion and the detection limit is as low as 0.087 pM (with the signal-to-noise ratio of 3). The relative standard deviation is 2.3% (for three repeated measurements). Furthermore, the ECL signal of Ru-dpq under a constant potential (1.2 V) is extremely stable and the intensity could be maintained over 600 s, which promotes us to determine the concentration of GSH via chronoamperometry .
研究领域:
分析化学
·
电化学
·
生物分析
✓ 已验证
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Bing Qiu,Chao Yuan,Mingtai Sun,Weijie Hu,Hua Tan,Suhua Wang
Owing to their unique plasmonic properties, noble metals have been the materials of choice for photovoltaics, photocatalysis and sensors. Here, we demonstrate novel gold(Au) monolayers with tailorable particle diameters and optical property on transparent indium tin oxide (ITO) using a simple electrochemical deposition. The nanoparticles on ITO are spherical and isolated, and are identified as Au 0 nanoparticles. The gold nanoparticles are uniformly distributed on ITO surface, but the gold nanoparticle sizes increase and the particle population densities decrease at lower current densities, resulting in higher light scattering. There is a positive correlation between mean particle size and maximum extinction wavelength of gold nanoparticles prepared with different current densities under a fixed total charge, whereas the maximum extinction wavelength of gold nanoparticles does not change with the total charge under the fixed current densities. The localized surface plasmon resonance change of Au nanoparticles on ITO can be effectively tuned by regulating deposition current density. With the existence of alkanethiols on Au monolayers surface, the original pink color of gold monolayers changed to blue after immersion in toluene for 30 min, indicating hydrophobic force produced by oil-in-water (O/W) or water-in-oil (W/O) phenomenon caused gold nanoparticles to migrate and produce a color change.
研究领域:
材料科学
·
光学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL LETTERS
·
2023
·
IF 2
Jian Lin,Jiawen Yin,Wanlei Gao,Qinghui Jin
Chemical oxygen demand (COD) is an important indicator of the degree of organic pollution in water. However, the development of integrated and batch COD electrochemical sensors has always been challenging. In this study, a three-electrode integrated electrochemical sensor for the measurement of COD in surface water was evaluated. Using microfabrication with a microelectromechanical system (MEMS), the sensor was mass-produced and integrated with boron-doped diamond (BDD), Pt, and Ag/AgCl electrodes on the chip. The determination of glucose in optimal conditions provided a linear range from 5 to 200 mg L−1, a detection limit of 3.899 mg L−1, and satisfactory linearity (R2) of 0.998. As the sensor was fabricated by MEMS technology, good reproducibility was experimentally verified with relative standard deviations less than 4%, which suggests mass production of the sensor. The sensor was calibrated to be relatively stable in the presence of Cl− and NO2−. A low-cost, miniature (6 mm2), and stable COD sensor was designed using microfabrication technology that may be mass-produced to build a water quality detection network in the Internet of Things era.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）