WEAR
·
2025
·
IF 6.1
Zhijun CHEN,Qiusheng YAN,Jisheng PAN,Hanhao LIU,Kaiyuan LUO,Jingyuan ZHENG
In photocatalytic-assisted magnetorheological polishing(PMRP), both the opacity of the magnetorheological fluid and the non-magnetic properties of the photocatalyst limit the processing efficiency and quality of SiC wafers. In this paper, the magnetorheological fluid is prepared by using photocatalysts with different physical phases(liquid/solid) and properties(magnetic/non-magnetic), and then the friction chemical mechanism is carried out on SiC. The results show that the transmittance of the magnetorheological fluid and the distribution state of the photocatalyst synergistically cooperate to control the chemical oxidation rate of single-crystal SiC. When using magnetic particles with photocatalytic coatings for processing, the photocatalytic reaction spots can be effectively constrained and the SiC oxidation efficiency can be improved.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2020
·Vol. 15
·期 3
·538-551
·
IF 3.552
Deng Xiaoyan,Wang Luxing,Xiu Qihui,Wang Ying,Han Hong,Dai Dongmei,Xu Yongji,Gao Hongtao,Liu Xien
In this work, an adsorbent, which we call MnPT, was prepared by combining MnO 2 , polyethylenimine and tannic acid, and exhibited efficient performance for Cu(II) and Cr(VI) removal from aqueous solution. The oxygen/nitrogen-containing functional groups on the surface of MnPT might increase the enrichment of metal ions by complexation. The maximum adsorption capacities of MnPT for Cu(II) and Cr(VI) were 121.5 and 790.2 mg·g −1 , respectively. The surface complexation formation model was used to elucidate the physicochemical interplay in the process of Cu(II) and Cr(VI) co-adsorption on MnPT. Electrostatic force, solvation action, adsorbate-adsorbate lateral interaction, and complexation were involved in the spontaneous adsorption process. Physical electrostatic action was dominant in the initial stage, whereas chemical action was the driving force leading to adsorption equilibrium. It should be noted that after adsorption on the surface of MnPT, Cr(VI) reacted with some reducing functional groups (hydroxylamine-NH 2 ) and was converted into Cr(III). The adsorption capacity declined by 12% after recycling five times. Understanding the adsorption mechanism might provide a technical basis for the procedural design of heavy metal adsorbents. This MnPT nanocomposite has been proven to be a low-cost, efficient, and promising adsorbent for removing heavy metal ions from wastewater.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
AICHE JOURNAL
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2019
·Vol. 66
·期 2
·e16841
·
IF 3.463
Chong Shen,Minjing Shang,Hong Zhang,Yuanhai Su
In this work, we report a simple and inexpensive UV-LEDs based photomicroreactor assembly constructed by commercially available components. The photoisomerization of norbornadiene to quadricyclane was selected to validate this novel photomicroreactor design. Mass transport limitation was eliminated and indicated by dimensionless numbers Fo and Da II , and photons loss was evaluated considering the absorption and reflection of the microreactor walls. The solvents, photosensitizers, and light sources selections were optimized for achieving better photochemical performance and mechanistic insights. The detailed comparison between the high-pressure mercury arc lamp and the UV-LEDs strip revealed great potential of UV-LEDs as appealing light source for photochemical transformations. Moreover, the reaction mechanism was thoroughly discussed and illustrated by the Jablonski diagram indicating electronic states transitions. According to possible intermediate steps, a kinetic model was proposed with the reaction rate constant being correlated with the photon flux, which is valuable for process optimization and further understanding reaction mechanisms.
研究领域:
化学工程
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光化学
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反应动力学
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DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Xingyu Xiao,Liangliang Liu,Junhao Ma,Yuan Ren,Xiaowei Cheng,Yongheng Zhu,Dongyuan Zhao,Ahmed A. Elzatahry,Abdulaziz Alghamdi,Yonghui Deng
Owing to their distinct chemical and physical properties, mesoporous metal oxide semiconductors have shown great application potential in catalysis, electrochemistry, energy conversion, and energy storage. In this study, mesoporous crystalline SnO2 materials have been synthesized through an evaporation-induced co-assembly (EICA) method using poly(ethylene oxide)-b-polystyrene diblock copolymers as the template, tin chlorides as the tin sources, and tetrahydrofuran as the solvent. By controlling conditions of the co-assembly process and employing a carbon-supported thermal treatment strategy, highly ordered mesoporous SnO2 materials with a hexagonal mesostructure (space group P63/mmc) and crystalline pore walls can be obtained. The mesoporous SnO2 is employed for fabricating gas sensor nanodevices which exhibit an excellent sensing performance toward H2S with high sensitivity (170, 50 ppm) and superior stability, owing to its high surface area (98 m2/g), well-connected mesopores of ca. 18.0 nm, and high density of active sites in the crystalline pore walls. The chemical mechanism study reveals that both SO2 and SnS2 are generated during the gas sensing process on the SnO2-based sensors.
研究领域:
材料科学
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传感技术
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DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2019
·
IF 5.714
Kai Zheng,Heping Li,Liping Xu,Shengbin Li,Luying Wang,Xiaoying Wen,Qingyou Liu
Pyrite weathering often occurs in nature and causes heavy metal ion pollution and acid mine drainage during the process. Humic acid (HA) is a critical natural organic material that can bind metal ions, thus affecting metal transfer and transformation. In this work, in situ electrochemical techniques combined with spectroscopic analysis were adopted to investigate the interfacial processes involved in pyrite weathering with/without HA. The results showed that the pyrite weathering mechanism with/without HA is FeS 2 → Fe 2+ + 2S 0 + 2e − . The presence of HA did not change the pyrite weathering mechanism, but HA adsorbs on the pyrite surface and inhibits the further transformation of sulfur. Furthermore, HA and Fe(II) ions can form complex at 45.0 °C. Increased concentration of HA, decreased HA solution acidity or decreased environmental temperature would all weaken the pyrite weathering, for the above conditions cause pyrite weathering to have a larger resistance of the double layer and a larger passive film resistance. Pyrite will release 73.7 g m −2 ·y −1 Fe 2+ to solution at pH 4.5, and the amount decreases to 36.8 g m −2 ·y −1 in the presence of 100 mg/L HA. This study provides an in situ electrochemical method for the assessment of pyrite weathering.
研究领域:
环境科学
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地球化学
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产品关联
DOI
PubMed
高影响因子
ELECTROCHEMISTRY
·
2022
·Vol. 90
·期 10
·107004-107004
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IF 1.777
Gong CHEN,Dingwei MIN,Yipeng HUANG
As a way to explore methods to capture and transform CO2 into useful carbon materials, the electrochemical mechanism of carbonate ion reduction in molten Li2CO3–K2CO3 eutectic mixtures is studied by cyclic voltammetry, chronopotentiometry, and chronocoulometry. Evidence indicates CO32− to undergo reduction to produce solid carbon before the alkali metal ions Li+ and K+. The electrode reactions consist of a diffusion-controlled, totally irreversible process comprising a one-step electron transfer. Notably, the described electrochemical process produces carbon sheets, submicron carbon tubes, or submicron carbon particles, depending on the applied cathodic overpotential. When O2− ions are released as part of the electrochemical reduction of CO32−, some of these ions immediately combine with Li+ to form insoluble Li2O, which are disadvantageous processes from the standpoint of CO2 capture in the cathodic region. Results suggest thus that a type of molten salt electrolyte in which alkali metal oxides are highly soluble should be employed for effective molten salt CO2 capture and electrochemical transformation.
研究领域:
材料科学
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电化学工程
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DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2022
·
IF 11.889
Peng Cheng,Yingchuan Zhang,Nianfang Ma,Lining Wang,Liqun Jiang,Zhen Fang,Yitong Wang,Xiangping Tan
Microbial fuel cell (MFC) exhibits huge potentials in disposing wastewater and extra energy consumption. Exploring useful microorganisms for MFC is the crucial section. Herein, the electrochemical mechanism of extracellular anaerobic respiration in MFC inoculated with gram-positive Rhodococcus pyridinivorans HR-1, was first revealed. The MFC exhibited rapid recovery of currents on anode, and could recover to maximum output within one hour, with redox peaks near −0.38 and −0.18 V through electron transfer between the biofilm and anode. When the biofilm-based pathway was blocked by wrapping the anode with Millipore filter membrane, HR-1 inoculated MFC could still generate electricity within a longer recovery period (∼35 h) during anolyte exchange. This was proposed as a self-secreted electron shuttle pathway for electron transfer in R. pyridinivorans HR-1. Cyclic voltammetry analysis revealed that the biofilm-based and self-secreted electron shuttle-based pathways co-existed in R. pyridinivorans HR-1 inoculated MFC, which could play synergistic roles in electricity generation.
研究领域:
微生物学
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环境科学
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电化学
✓ 已验证
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
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2022
·
IF 7.336
Ye Liu,Zhe Li,Yanjie Cheng,Ru Wang,Yunhui Shi
Advanced secondary energy storage technologies and key components are crucial to the efficient use of energy resources. Layered antimonene can facilitate ions transport and intercalation. However, the electrochemical mechanism of antimonene is very much a gray area. Herein, we show that the electrolyte ions can make appreciable differences in the energy storage behavior of antimonene. Accordingly, a high value of 599 F g −1 can be obtained by scanning antimonene electrode in 1 M H 2 SO 4 at a rate of 5 mV s −1 , which is more than twice the capacitance of those KOH, LiOH and LiCl based electrolyte systems. Systematic investigation including kinetics simulation and extrapolation of surface charge suggests a mixture of surface-controlled and battery-like Faradaic responses of antimonene in acid electrolyte. Electrochemical quartz crystal microbalance (EQCM) combined with first-principles calculation further reveals that hydrated H + is expected to access the “inner” surface sites of antimonene and thus insert or intercalate into the antimonene nanosheets. Notably, an asymmetric supercapacitor composed of antimonene positrode and carbon nanotube negatrode exhibits a wide operating voltage of 1.8 V, a relatively high energy density of 46 Wh Kg −1 at a power density of 450 W Kg −1 and great cycling performance (capacitance retention of up to 112.7% after 5000 cycles, 1.5 A g −1 ). The paper offers fundamental insights into the influence of electrolyte ions on the electrochemical behavior of 2D Xenes and pushes back the frontiers of designing energy storage systems.
研究领域:
材料科学
·
能源存储技术
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产品关联
DOI
高影响因子
ACS Nano
·
2022
·
IF 18.027
Zhiquan He,Tengda Rong,Yan Li,Junjie Ma,Quanshui Li,Furong Wu,Yuhang Wang,Fengping Wang
Two-dimensional (2D) MXenes are attractive candidates as surface-enhanced Raman scattering (SERS) substrates because of their metallic conductivity and abundant surface terminations. Herein, we report the facile synthesis of bimetallic solid-solution TiVC (MXene) and its application in SERS. The few-layered MXene nanosheets with high crystallinity were successfully prepared using a one-step chemical etching method without ultrasonic and organic solvent intercalation steps. SERS activity of the as-prepared MXene was investigated by fabricating free-standing TiVC film as the substrate. A SERS enhancement factor of 1012 and femtomolar-level detection limit were confirmed using rhodamine 6G as a model dye with 532 nm excitation. The fluorescent signal of the rhodamine 6G dye was effectively quenched, making the SERS spectrum clearly distinguishable. Furthermore, we demonstrate that the TiVC-analyte system with ultrahigh sensitivity is dominated by the chemical mechanism (CM) based on the experimental and simulation results. The abundant density of states near the Fermi level of the TiVC and the strong interaction between the TiVC and analyte promote the intermolecular charge transfer resonance in the TiVC–analyte complex, resulting in significant Raman enhancement. Additionally, several other probe molecules were used for SERS detection to further verify CM-based selectivity enhancement on the TiVC substrates. This work provides guidance for the facile synthesis of 2D MXene and its application in ultrasensitive SERS detection.
研究领域:
材料科学
·
分析化学
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产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
·
2021
·
IF 4.126
Leiqian Zhang,Lingfeng Ge,Guanjie He,Zhihong Tian,Jiajia Huang,Jingtao Wang,Dan J.L. Brett,Johan Hofkens,Feili Lai,Tianxi Liu
The development of effective rechargeable potassium–sulfur (K–S) batteries has been retarded by a severe polysulfide shuttle effect and low sulfur content in the cathode (generally less than 40 wt %). Herein, a series of sulfur-linked polymers with different numbers of allyloxy linkers have been chosen to explore their effect on the performance of K–S batteries. By taking sulfur-linked tetra(allyloxy)-1,4-benzoquinone polymer (poly(S4-TABQ)) as the cathode of K–S batteries, its maximal sulfur content reaches ∼71 wt %, which displays a high capacity retention of 94.5% after 200 cycles (only 0.027% loss per cycle). Theoretical analyses and density functional theory calculations show that the abundant allyloxy linkers in poly(S4-TABQ) cathodes play a vital role in inhibiting the polysulfide shuttle effect and realizing high capacity, owing to the strong interaction of the allyloxy moieties with potassium polysulfides and the accelerated charge transfer during charge/discharge process. Moreover, ex situ X-ray photoelectron spectroscopy and ultraviolet–visible spectroscopy analysis are conducted to explore the electrochemical mechanism in poly(S4-TABQ) cathodes, indicating that −C-Sn–·K+ (n = 2–6) and K2Sn (n = 2–6) coexist in K–S batteries without the formation of K2S groups. This study provides a novel insight into the application of sulfur-linked polymers as cathode material in potassium–sulfur batteries.
研究领域:
材料科学
·
电化学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Tao Xia,Yifeng Han,Chuanhui Zhu,Zhongxiong Sun,Chongyang Yuan,Qi Cui,Jin-Guang Cheng,Wei Du,Wenting Li,Kui Xie,Keke Huang,Shouhua Feng,David Walker,Man-Rong Li
High-pressure heaters in large volume presses must reconcile potentially contradictory properties, and the whole high-pressure and high-temperature (HPHT) community has been engaged for years to seek a better heater. LaCrO3 (LCO)-based ceramic heaters have been widely applied in multianvil apparatus; however, their performance is far from satisfactory, motivating further research on the chemical optimization strategy and corresponding thermochemical mechanism. Here, we adopted a chemical-screening strategy and manufactured tubular heaters using the electrically, chemically, and mechanically optimized Sr–Cu codoped La0.9Sr0.1Cr0.8Cu0.2O3−δ (LSCCuO-9182). HPHT examinations of cylindrical LSCCuO-9182 heaters on Walker-type multianvil apparatuses demonstrated a small temperature gradient, robust thermochemical stability, and excellent compatibility with high-pressure assemblies below 2273 K and 10 GPa. Thermochemical mechanism analysis revealed that the temperature limitation of the LSCCuO-9182 heater was related to the autoredox process of the Cu dopant and Cr and the exchanging ionic migration of Cu and Mg between the LSCCuO-9182 heater and the MgO sleeve. Our combinatorial strategy coupled with thermochemical mechanism analysis makes the prioritization of contradictory objectives more rational, yields reliable LCO heaters, and sheds light on further improvement of the temperature limitation and thermochemical stability.
研究领域:
材料科学
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化学
·
物理学
·
高压科学
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Ningning Feng,Bingliang Wang,Zhuo Yu,Yuming Gu,Lili Xu,Jing Ma,Yonggang Wang,Yongyao Xia
Li–CO2 batteries have attracted worldwide attention because of their dual characteristics of high energy density and effective CO2 capture. However, the basic electrochemistry mechanism involved has been unclear, which is mainly confused by the complicated decomposition of organic electrolytes. Herein, water-in-salt (WIS, LiTFSI/H2O 21.0 mol/1 kg) has been explored as a suitable electrolyte for the first time to investigate the reaction mechanism of Li–CO2 batteries with different cathodes (carbon nanotube (CNT) and Mo2C/CNT, respectively). An Mo2C-based Li–CO2 battery with WIS delivers a higher energy efficiency of 83% and a superior cyclability, compared to those of the CNT-based counterpart cell. Through various ex/in situ qualitative/quantitative characterizations, the Mo2C-based Li–CO2 battery with WIS can operate on the reversible conversion of CO2-to-Li2C2O4 ((e–/CO2)ideal = 1) at lower discharge/charge overpotentials, while the CNT-based counterpart cell is based on the formation/decomposition of Li2CO3 ((e–/CO2)ideal ≈ 1.33) at high overpotentials. Such a difference in CO2 reduction products stems from the stronger interaction between Mo2C(101) and Li2C2O4 than that of the CNT and Li2C2O4 based on the density functional theory calculations, resulting in the selective stabilization of the intermediate product Li2C2O4 on the Mo2C surface.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）