SOLID STATE IONICS
·
2016
·
IF 2.38
Guofeng Xu,Qingrui Xue,Jianling Li,Zhanyu Li,Xinping Li,Tianheng Yu,Jiguang Li,Xindong Wang,Feiyu Kang
Lithium-excess layered cathode materials Li[Li 0.2 Mn 0.54 − x Sm x Co 0.13 Ni 0.13 ]O 2 (x = 0, 0.01, 0.03, 0.05) with different quantities of Sm were synthesized by the coprecipitation-calcination method. The rare earth element samarium (Sm) was introduced into the structure of Li[Li 0.2 Mn 0.54 Co 0.13 Ni 0.13 ]O 2 as the replacement at Mn sites. The refinement unit cell parameters from the X-ray powder diffraction patterns illustrate the doping of Sm facilitates enlarging the lithium ions diffusion passageway space of the Li[Li 0 . 2 Mn 0.54 Co 0 . 13 Ni 0.13 ]O 2 structure. The Li[Li 0.2 Mn 0.51 Sm 0.03 Co 0.13 Ni 0.13 ]O 2 electrode presented the best electrochemistry properties. The initial discharge capacity is 287.5 mAh g − 1 and the initial coulombic efficiency increases from 81.31% to 85.34% with a constant current density of 12.5 mA g − 1 , which can be attributed to the suppression of the oxygen release from the structure at the initial charge-discharge process. The Li[Li 0·2 Mn 0.51 Sm 0.03 Co 0.13 Ni 0.13 ]O 2 electrode delivers 236.1 mAh g − 1 after 40 cycles and the capacity retention ratio is 82.12% while only 206.8 mAh g − 1 and 70.85% are obtained after 40 times of cycling for the pristine electrode. The Nyquist plots indicate that the electrical conductivity and interfacial electrochemical reaction activity increase as well.
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高影响因子
GREEN CHEMISTRY
·
2014
·Vol. 17
·期 1
·335-342
·
IF 6.852
Muge Niu,Yucui Hou,Shuhang Ren,Wenhua Wang,Qitian Zheng,Weize Wu
Conversion of cellulose, the most abundant biomass, shows a high selectivity to yield formic acid (FA), when oxidized by O2 in NaVO3–H2SO4 aqueous solution. This conversion involves various reactions including hydrolysis and oxidation. In this work, the relationships between these reactions were studied. There are mainly two hydrolyses and two oxidations occurring in the conversion: initial hydrolysis (from cellulose to monosaccharides) and deep hydrolysis (from monosaccharides to levulinic acid); catalytic oxidation (from monosaccharides to FA) and ordinary oxidation (from levulinic acid to acetic acid). Among these four reactions, catalytic oxidation to FA and deep hydrolysis to byproducts are competitive. The increasing rate of deep hydrolysis is faster than that of catalytic oxidation, when temperature is increased. Catalytic oxidation is promoted and deep hydrolysis is suppressed, when the O2 pressure is increased. Moreover, deep hydrolysis is promoted and catalytic oxidation is suppressed, when H2SO4 concentration is increased. The hydrolysis–oxidation pathway of this conversion was proposed. Thus, the byproducts could be inhibited, and FA-oriented transformation could be realized.
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高影响因子
Journal of Physical Chemistry C
·
2014
·
IF 4.835
Sujie Chang,Shigang Ruan,Erlong Wu,Weixin Huang
Oxide-on-metal particles with exposed interfaces exhibit wealthy structures and functions, but their facile synthesis remains as a challenge. Herein we report a facile O2-assisted hydrothermal method to synthesize CeO2-on-Ag particles with different CeO2 thicknesses. In this novel approach Ag particles catalyze the O2 + H2O reaction to form surface hydroxyls that induce the preferential nucleation of Ce(OH)3 on the surfaces of Ag particles, eventually forming CeO2 adlayers on Ag particles. CeO2-on-Ag particles exhibit the CeO2 thickness-dependent SERS effect in which their best SERS effect is 2 orders stronger than that of Ag particles. They also exhibit CeO2 thickness-dependent catalytic performance in CO oxidation in which the best one is as active as traditional CeO2-supported Ag catalyst. These results open up new opportunities to synthesize oxide-on-metal particles and explore their functions by tuning the oxide adlayer thickness.
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高影响因子
MATERIALS LETTERS
·
2014
·
IF 2.269
Ming Yan,Yan Yan,Chao Wang,Wei Lu,Weidong Shi
In this letter, Ni 2+ doped InVO 4 nanocrystals were successfully synthesized by a simple one-pot microwave-assisted method. The energy bandgap of obtained samples can be precisely controlled by varying the Ni 2+ doping amount. The O 2 production rate of obtained Ni–InVO 4 nanocrystals is higher than that of pure InVO 4 nanocrystals under visible-light, which can be ascribed to the narrowed band gaps. The corresponding 1% doped sample N1 has the highest O 2 production rate (394 μmol/h) in all samples, which is 66% higher than the undoped sample N0.
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高影响因子
Journal of Energy Storage
·
2022
·
IF 8.907
De-Ming Zhu,Fan Bai,Yi-Nan Zhang,Ya-Nan Yang,Zhuang Sun,Jun-Wen Deng,Tao Zhang
Solid-state Li-O 2 batteries (SSLOBs) have been denoted as the holy grail in next-generation Li metal batteries for their high theoretical energy density , manipulation of ambient air to energy storage as well as high safety. However, the solid rigid interfaces both at the cathode and anode side introduce ultra-high resistances in the battery system and impede its operation under ambient temperature. Moreover, the high-reductive Li anode and semi-open cathode would cause severe side reactions during cycling which further degrade battery performance. To manage the above-mentioned issues, a rationally designed SSLOBs based on plastic crystal electrolyte is proposed in this study to enable SSLOBs operation at ambient temperature and in full charge-discharge mode. The brand-new Li-O 2 battery has been improved mainly from two aspects. First, we propose a polyacrylonitrile (PAN) modified succinonitrile (SN) electrolyte (PAN-SN) to retard the polymerization of SN and meanwhile suppress the degradation of Li ionic conductivity. Second, we propose an alternative mixed electron/ion complex conductor (MEIC) cathode to coordinate with plastic crystal electrolyte with an expanded Li-O 2 reactive zone and improved interfacial charge transfer during the charge-discharge process. The fabricated flexible SSLOBs based on PAN-SN electrolyte and MEIC cathode could be successfully fully charged-discharged (cutoff 2.0–4.5 V) for tens of cycles at ambient temperature under simulated air condition (20 vol% oxygen), with high-capacity retention of around 85 %.
研究领域:
能源存储
·
电池技术
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材料科学
·
电化学
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高影响因子
JOURNAL OF PHYSICS D-APPLIED PHYSICS
·
2024
·Vol. 57
·期 43
·435204
·
IF 3.1
Pengyu Zhao,Yikang Jia,Sihong Ma,Rui Zhang,Kaiyu Li,Tianyi Song,Jianbao Zheng,Jingyao Zhang,Li Guo,Dingxin Liu,Xiaohua Wang,Mingzhe Rong
Methicillin-resistant Staphylococcus aureus (MRSA) presents a significant threat due to the multiple resistance to antibiotics, leading to severe and challenging-to-treat infections. Plasma-activated saline (PAS) prepared by plasma gases, could efficiently inactivate various pathogenic bacteria including both sensitive and antibiotic-resistant bacteria. In this study, the PAS was prepared by plasma gases with different ratios of N2 and O2 activated by gliding arc discharge. First, the gaseous reactive species in the plasma gases were compared, revealing that the highest levels of NOx including NO2 and N2O5 were generated in the gases with the N2/O2 ratios of 4:6, 5:5, and 6:4. Subsequently, the PAS prepared by the two plasma-activated gases at the N2/O2 ratios of 5:5 and 6:4 exhibited the strongest inactivation effects on both planktic MRSA and biofilms. Furthermore, the aqueous reactive species in the PAS exhibited varied change trends with the increasing N2/O2 ratios. Additionally, ultraviolet spectroscopy combined with the probe of N, N-diethyl-p-phenylenediamine was applied for the detection of O2NOO− in the PAS, and the levels of O2NOO− in the PAS were positively correlated with the inactivation effects. Moreover, the PAS induced varying levels of nitration modification on the soluble proteins in MRSA cells, which were related to the intensities of O2NOO− in the PAS. This study regulated the reactive species in the PAS through gas composition and explored the inactivation mechanism of the PAS, providing a new strategy to promote the preparation efficiency of plasma-activated solutions for biomedical applications.
研究领域:
微生物学
·
生物医学工程
·
感染病学
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高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zixian Qin,Yuxiu Sun,Zhengqing Zhang,Chenxu Zhang,Chi Tang,Chenxu Geng,Zhihua Qiao
Oxygen/nitrogen (O 2 /N 2 ) separation is of great importance but faces huge challenges owing to their similar molecular size and close polarity. In this work, we construct a polymer of intrinsic microporosity (PIM-1) based mixed matrix membrane (MMM) for efficient O 2 /N 2 separation by using ZIF-8 as the sieving filler along with surface modification of o-carborane (o-CB) to strengthen selective N 2 adsorption fixation as well as polymer-filler interfaces. Markedly, the o-CB on the outer surface of ZIF-8 not only affords the requisite interfacial compatibility in molecular sieving MMMs, but also increases the diffusion difference between O 2 and N 2 by the preferential adsorption with N 2 molecules. This synergistic effect of molecular sieving and adsorption inhibition achieves efficient O 2 /N 2 diffusion differential separation. As expected, the optimal membrane with o-CB-ZIF-8 loading of 35 wt% exhibits an O 2 permeability of 796.5 Barrer and a mixed O 2 /N 2 selectivity of 8.9 with O 2 /N 2 (20:80, vol.) mixtures, exceeding the latest 2015 upper bound limits. Moreover, the according membrane module with o-CB-ZIF-8 loading of 20 wt% also displays moderate O 2 permeability of 391.7 Barrer and O 2 /N 2 selectivity of 5.5 under pressure of 1 bar. This work may provide a feasible platform for designing high-performance MOF-based membranes in air separations.
研究领域:
材料科学
·
分离技术
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高影响因子
CHINESE JOURNAL OF ANALYTICAL CHEMISTRY
·
2020
·
IF 0.936
Liang WANG,Zhang-Quan PENG
Development of lithium-oxygen (Li-O 2 ) batteries is hindered by large overpotentials, low energy efficiency and unsatisfactory cycling life, which are predominately caused by the oxygen evolution reaction (OER) involving sluggish oxidation of lithium peroxide (Li 2 O 2 ). Herein, a highly-efficient soluble redox mediator (RM) of N , N’ -Diphenyl- p -phenylenediamine (DPPD) is introduced to catalyze the oxygen evolution reaction for Li-O 2 batteries. During charging process, DPPD is electrochemically oxidized into DPPD + , which can chemically decompose Li 2 O 2 on the cathode with a much-reduced overpotential. The in-situ differential electrochemical mass spectrometry confirms that the charging process is dominated by Li 2 O 2 decomposition. With the assistance of DPPD, Li-O 2 cells can achieve lower charging potential, improved cycling stability, and prolonged lifespan (294 cycles) which is three times longer than that of tetrathiafulvalene counterpart. This work presents a credible and viable opportunity for long lifespan Li-O 2 batteries.
研究领域:
电化学
·
能源材料科学
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DOI
高影响因子
NANOTECHNOLOGY
·
2019
·Vol. 30
·期 36
·364003
·
IF 3.399
Chao Li,Yijie Liu,Bojie Li,Fan Zhang,Zhu Cheng,Ping He,Haoshen Zhou
All-solid-state Li–O2 batteries are receiving intense interest because of the substitution of solid electrolytes for toxic and flammable liquid electrolytes. However, new issues are arising in the aspect of the electrolyte cathode interface. On the one hand, in a traditional sandwiched battery structure, the reaction sites of the cathode are restricted to the finite planar electrode–electrolyte interface, resulting in limited performance of all-solid-state Li–O2 batteries. On the other hand, integrating the electrolyte with the cathode to achieve good interfacial contact often requires complex sintering processes. Herein, this work reports a solid electrolyte cathode assembly (SECA) which consists of a dense Li1.5Al0.5Ge1.5P3O12 (LAGP) layer and a carbon coated porous LAGP layer fabricated by facilely one-step sintering. As a result, Li–O2 batteries adopting the SECA showed a relatively high discharge capacity of 0.48 mAh cm−2 at 5 μA cm−2. Besides, the batteries could sustain six full cycles with a restricted capacity of 0.08 mAh cm−2 at 10 μA cm−2. It was found that the high capacity can be attributed to the high surface area of porous cathode structure.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
Journal of Physical Chemistry C
·
2014
·
IF 4.835
Wugang Fan,Xiangxin Guo,Dongdong Xiao,Lin Gu
Gold nanoparticles (AuNPs) anchored to vertically aligned carbon nanotubes (VACNTs) act as additional nucleation sites for the Li2O2 growth, leading to the decreased size while increased density of Li2O2 particles in process of discharge. Correspondingly, at the deep discharge to 2.0 V the batteries show increased specific capacity. Upon charge, the AuNPs exhibit promotion effect on the Li2O2 decomposition by improving the conduction property of the discharge-formed particles, rather than by imposing the conventional electrocatalytic effect on the oxygen evolution reaction. Moreover, the AuNPs show promotion effect on decomposition of carbonate species arising from the side reactions. These effects consequently lead to the reduced charge overpotentials and extended cycle operation of the batteries. The results here provide a new as well as clear picture on the role of incorporated AuNPs in the Li2O2 formation and decomposition, which would be helpful for better understanding and constructing of high-performance air cathodes.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Binbin Shao,Yufan Chen,Deli Wu,Chaomeng Dai,Yalei Zhang
Structural Fe(II/III) hydroxides on the shell of nano-zerovalent iron (nZVI) are reactive sites for As(III) adsorption. Well-controlled structural Fe(II) hydroxides (SFH) is prepared to serve for As(III) removal in present study. With oxygen As(III) removal by SFH occurred efficiently but the removal efficiency was greatly reduced under anoxic conditions. The mineral transformation from SFH to lepidocrocite probably contributed to the robust removal efficiency of As(III). It is found that Cu(II), Cr(VI) and NO 2 − in aqueous solution could act as oxidants and promote the mineral transformation of SFH. A more efficient As(III) removal was therefore observed without oxygen. The removal efficiency decreased in the order O 2 /SFH ≈ Cu(II)/SFH > Cr(VI)/SFH ≈ NO 2 − /SFH at near neutral pH. The removal efficiency was less dependent on the initial pH for O 2 /SFH and Cu(II)/SFH systems than Cr(VI)/SFH and NO 2 − /SFH systems. Distribution of As on solid phases was able to describe the removal mechanism of As(III), and the results showed that the mineral transformation promoted the precipitation process and inhibited outer-sphere complexation, thus leading to enhanced As removal. With Cu(II), Cr(VI) and NO 2 − , the generation of oxidants from SFH transformation drove As(III) oxidation, and contributed to total As removal.
研究领域:
环境科学
·
化学
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高影响因子
SusMat
·
2021
·Vol. 1
·期 3
·448-457
·
IF 0
Zhaomin Chen,Xiaoqing Gu,Yutong Guo,Xin Wang,Mingwang Shao,Bin Dong,Zhenhui Kang
Electrochemical cell can overcome the inherent intermittence of the renewable energy sources, thus showing great potentials in applications ranging from electrical energy storage to future smart grid. However, the current electrochemical cells could not achieve the “total green” feature by fully utilizing the clean and abundant O 2 /H 2 O redox couples due to the enormous overpotentials for both oxygen reduction reaction (ORR) and oxygen release reaction (OER). Herein, we report a “total green” electrochemical composite film cell based on carbon dots (CDots), which can realize both ORR and OER in the acid environment. The in-air voltage generation (0.95 V, with a maximum power of 5.3 μW) relies on the multiple-electron-transfer redox chemical reaction between the two active components inside the composite film, that is, ORR/OER of CDots and the redox reaction of polyaniline (PANI) on the electrode and the resulting proton concentration gradient. Interestingly, the cell can be self-recovered at low load, recharged by adding H 2 O 2 , or electrocharged at high load. We anticipate that current study may open up new opportunities for designing and developing total-green energy storage and conversion systems for diverse applications.
研究领域:
材料科学
·
能源技术
·
环境科学
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危险品化学品经营许可证（带存储）