JOURNAL OF POWER SOURCES
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2017
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IF 6.395
Zongbao Zhang,Yang Zhou,Yangyang Cai,Hui Liu,Qiqi Qin,Xubing Lu,Xingsen Gao,Lingling Shui,Sujuan Wu,Jun-Ming Liu
Planar perovskite solar cells (PSCs) based on CH 3 NH 3 PbI 3- x (SCN) x (SCN: thiocyanate) active layer and low-temperature processed TiO 2 films are fabricated by a sequential two-step method in ambient air. Here, alkali thiocyanates (NaSCN, KSCN) are added into Pb(SCN) 2 precursor to improve the microstructure of CH 3 NH 3 PbI 3- x (SCN) x perovskite layers and performance of the as-prepared PSCs. At the optimum concentrations of alkali thiocyanates as additives, the as-prepared NaSCN-modified and KSCN-modified PSCs demonstrate the efficiencies of 16.59% and 15.63% respectively, being much higher than 12.73% of the reference PSCs without additives. This improvement is primarily ascribed to the enhanced electron transport , reduced recombination rates and much improved microstructures with large grain size and low defect density at grain boundaries. Importantly, it is revealed that the modified PSCs at the optimized concentrations of alkali thiocyanates additives exhibit remarkably improved stability than the reference PSCs against humid circumstance, and a continuous exposure to humid air without encapsulation over 45 days only records about 5% degradation of the efficiency. These findings provide a facile approach to fabricate efficient and stable PSCs by low processing temperature in ambient air, both of which are highly preferred for future practical applications of PSCs.
研究领域:
材料科学
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能源科学
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纳米技术
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光电化学
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半导体器件
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薄膜物理
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2022
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IF 9.794
Yuanyuan Li,Jun Cheng,Jianwei Li,Zhen Zeng,Yixuan Guo,Hongqiang Zhang,Hongbin Liu,Xiao Xu,Yiwei Rao,Deping Li,Lijie Ci
Sulfide solid state electrolytes capture much attention owing to their high conductivity and decent mechanical property. Nevertheless, the moisture instability and poor interfacial compatibility against lithium metal anode remain challenging and hinder the practical application. Herein, we report a novel indium (In) doping strategy based on the hard-soft-acid-base theory to tackle these issues. Optimized Li 7 P 2.9 S 10.9 In 0.1 electrolyte exhibits a high ionic conductivity of 4.1 × 10 −3 S cm −1 and achieves an enhanced interfacial compatibility. Importantly, as In partially replaces the phosphorus (P), the amount of released hydrogen sulfide can be significantly decreased and the air stability is improved. The all-solid-state battery assembled with the Li 7 P 2.9 S 10.9 In 0.1 electrolyte demonstrates a high discharge capacity and a good cycling stability under a high current density of 1.0 C. This work provides a practical and effective method to design sulfide-based solid-state electrolyte with high ionic conductivity and enhanced air stability for all-solid-state battery applications.
研究领域:
材料科学
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电化学
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能源存储
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固态离子学
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电池技术
✓ 已验证
DOI
高影响因子
Small
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2020
·Vol. 16
·期 43
·2004614
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IF 11.459
Xian Wang,Anrui Dong,Ziyi Zhu,Lulu Chai,Junyang Ding,Li Zhong,Ting-Ting Li,Yue Hu,Jinjie Qian,Shaoming Huang
In the preparation of nanomaterials, the kinetics and thermodynamics in the reaction can significantly affect the structures and phases of nanocrystals. Therefore, people are keen to adopt various synthetic strategies to accurately assemble the target nanocrystals, and reveal the underlying mechanism of the formation of specific structures. In this work, the total reaction time is adjusted to let the prepared MnCo Prussian blue analogous (MnCoPBA) crystals show four evolving morphological changes at different stages with the assistance of sodium dodecyl sulfate. Furthermore, it is clearly observed that the epitaxial growth along the (100) plane on the shell of MnCoPBA nanocrystals is favored, and the thermodynamics and kinetics in the morphology change process are analyzed in detail. Through the simple pyrolysis, MnCoPBA crystals can be successfully converted into the corresponding carbon composites, of which Mn 2 Co 2 C nanoparticles are evenly distributed in highly graphitized carbon matrix. Among them, PBA-III-700 performs good oxygen reduction reaction performance in alkaline solution with the half-wave potential of 0.801 V and diffusion-limited current density of 5.36 mA cm −2 , and its zinc-air battery exhibits the peak power density of 103.4 mW cm −2 competitive with commercial Pt/C.
研究领域:
材料化学
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纳米科学与技术
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电化学
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能源材料
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无机功能材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Yinwei Fu,Xiaofeng Lei,Huiming Yin,Xizheng Liu
Flexible lithium–air batteries (LABs) with a redox mediator (RM) in the electrolyte demonstrate enhanced round-trip efficiency. However, their cycle performance is unsatisfactory due to severe corrosion of the Li metal anode. Herein, we propose a two step gelatinization strategy to fabricate a gradient RMs (including LiI, TMPD, and DMPZ) gel electrolyte, in which the bare electrolyte gelatinization on the Li surface and then the electrolyte contained RMs sequentially gelled on the formed gel. The RMs mainly distributed at the surface and anchored at the cathode side. By suppressing the shuttle of RMs in the electrolyte and alleviating the passivation of the Li anode, the mid-charging potentials can reach 3.44 and 4.08 V at the 15th cycle with and without the LiI mediator, respectively. The energy efficiency is 63% even at the 150th cycle, whereas the corresponding energy efficiency are only 47% and 51% for the LABs with liquid and normal gel electrolytes, respectively. Moreover, the cycle life of the battery containing the gradient gel electrolyte is three times longer than that with the liquid electrolyte. The gel electrolyte further offers the flexibility of the device, and the laminated cells thus fabricated can readily operate under harsh bending conditions.
研究领域:
电化学
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能源材料
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纳米材料
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界面化学
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储能技术
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先进电池
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功能高分子
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柔性电子
✓ 已验证
DOI
高影响因子
FUEL
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2018
·
IF 4.908
Guoqing Wang,Yuyang Li,Lei Li,Fei Qi
Cellular instability of spherically expanding methanol/air flames was investigated in a constant-volume single-chamber cylindrical combustion vessel at initial temperatures of 373–423 K, initial pressures of 1–10 atm and equivalence ratios of 0.7–2.1. Flame morphology shows that the methanol/air flames suffer from cellular instability, especially at 5–10 atm. Stability analysis was performed to determine the logarithmic growth rate of disturbance, the critical Peclet number and the critical flame radius. The influences of initial temperature, initial pressure and equivalence ratio on cellular instability were analyzed to identify the influential factors. Both experimental results and stability analysis indicate cellular instability monotonically increases with increasing temperature or pressure and non-monotonically varies with increasing equivalence ratio. The reduced critical Peclet number and flame thickness slightly destabilize the flame surface as temperature increases. The almost unchanged critical Peclet number and the greatly reduced flame thickness with increasing pressure make the critical flame radius smaller and the flame surface more unstable at high pressures. The monotonically decreased critical Peclet number and the non-monotonically varied flame thickness result in the non-monotonic variation of cellular instability in methanol/air flames versus equivalence ratio. The critical flame radius consequently increases with increasing equivalence ratio under very rich conditions, while the corresponding flame surface becomes more smooth. The non-monotonic variation of cellular instability versus equivalence ratio is anticipated to exist widely in combustion of heavy fuels .
研究领域:
燃烧学
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热力学
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流体力学
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化学动力学
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能源工程
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
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2019
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IF 5.162
Bo Lv,Sha Zeng,Wei Yang,Jian Qiao,Chao Zhang,Chengfeng Zhu,Minghai Chen,Jiangtao Di,Qingwen Li
Recently, the development of high-performance bifunctional oxygen catalysts integrated with flexible conductive scaffolds for rechargeable metal-air batteries has attracted considerable interest, driving by fast-growing wearable electronics . Herein, we report a flexible bifunctional oxygen catalyst thin film consisting of Co–N–C bifunctional catalysts embedding in carbon nanotube (CNT) networks. The catalyst is readily prepared by pyrolysis of cobalt-based zeolitic imidazolate frameworks (ZIF-67) that are in-situ synthesized in CNT networks. Such catalyst film demonstrates very high catalytic activities for oxygen reduction (onset potential: 0.91 V, and half-wave potential: 0.87 V vs. RHE) and oxygen evolution (10 mA cm −2 at 1.58 V) reactions, high methanol tolerance property, and long-term stability (97% current retention). Moreover, our integrated catalyst film shows very good structure flexibility and robustness. Based on the obtained film air electrodes, flexible Zn–air batteries demonstrate low charging and discharging overpotentials (0.82 V at 1 mA cm −1 ) and excellent structure stability in the bending tests . These results indicate that presently reported catalyst films are potential air electrodes for flexible metal–air batteries.
研究领域:
材料科学
·
电化学
·
纳米能源
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先进功能材料
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可再生能源
✓ 已验证
DOI
高影响因子