Nanoscale
·
2019
·Vol. 11
·期 36
·16907-16918
·
IF 6.97
Hong Lin,Jian Mao,Minchao Qin,Zhilong Song,Wanjian Yin,Xinhui Lu,Wallace C. H. Choy
While red is one of the primary colors for display applications, the investigation of visible red emitting perovskites, particularly 2D perovskites, is relatively limited. In this work, we demonstrate a single-phase Ruddlesden–Popper quasi-2D (C3H7NH3)2CsPb2I7 perovskite for red color LEDs. Through increasing the annealing temperature of (C3H7NH3)2CsPb2I7 perovskite thin films, we have successfully achieved tunable emission wavelengths from 654 to 691 nm. Equally important, for all the quasi-2D perovskite LEDs, once the annealing temperature is fixed, the emission spectrum is independent of bias voltages, which is very important for their use in lighting and displays. With the analysis of the crystallinity, morphology, and thermodynamic stability of the quasi-2D perovskite, we find that the obtained (C3H7NH3)2CsPb2I7 perovskite is a single-phase quasi-2D perovskite with only n = 2 phase. Besides, we found that the red shifting of emission wavelength is caused by the increase of perovskite crystal size while increasing the annealing temperature. Our results also show that the temperature-induced color tunability can be applied to a series of quasi-2D perovskites with different alkylammonium cations. Importantly, we find that short alkylammonium spacers offer better electrical properties for efficient current transport and high performance in LED applications. This work contributes to controlling the optoelectronic properties of quasi-2D perovskites via controlling their crystal growth as well as paves the way to realize practical lighting and display applications of perovskite LEDs.
研究领域:
材料科学
·
光电功能材料
·
半导体器件
·
纳米结构材料
·
固态照明
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Xiangyang Zhuang,Yao Zhang,Lingxiao He,Yunfeng Zhu,Quan Shi,Quan Wang,Guanzhou Song,Xiaoxiao Yan,Liquan Li
Overheating caused by exothermic effect of magnesiothermic reduction reaction is usually considered as a drawback in preparing porous silicon anode materials for Li-ion batteries. However, in the present work, thermal effect is available in facile preparation of macroporous Si by tabletting pretreatment . The released heat in magnesiothermic reaction is easily accumulated on the tablet with high density, leading to the collapse of the mesoporous structure of the precursor and formation of uniform macroporous silicon . Such macroporous silicon shows a higher initial Coulomb efficiency (86.5%) and enhanced cycling stability in comparison with mesoporous silicon prepared without tabletting treatment. XRD analysis indicates that the reaction temperature decreases to 430–435 °C (based on set temperature), much lower than that of the reaction without pretreatment. Since the structure of product has less dependency on precursor, a wide variety of precursors can be used to synthesize macroporous silicon, e.g. low cost biosilica. Being ascribed to low reaction temperature, heating rate insensitivity, less dependency on precursor, enhanced cycling performance and high initial Coulomb efficiency of the Si products, the modified magnesiothermic reduction method is promising for application in fabricating Si anode.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
无机合成
·
功能材料
·
电池技术
✓ 已验证
DOI
高影响因子
IONICS
·
2019
·Vol. 26
·期 2
·649-660
·
IF 2.289
Yan Honglin,Ru Qiang,Gao Ping,Cheng Shikun,Ling Francis Chi-Chung
In the past few years, silane coupling agents are often used to modify the surface of silicon materials; however, researches in preparation of SiO X -based materials pyrolyzed from silane coupling agents are seldom reported. Hence, in order to prepare amorphous SiO X @C anodes for Li-ion storage, we adopted three kinds of silane coupling agents as organic silicon sources. The results show that silane coupling agents with vinyl group is the optimum organic silicon source. Owing to the strong chemical bonds of Si–O–C, amorphous SiO X particles are uniformly embedded in carbon matrix, forming monodisperse microbeads architecture with good buffer abilities. Therefore, the V-SiO X @C anodes derived from silane coupling agents with vinyl groups show good electrochemical performance, retaining a reversible discharge capacity of 940 mAh g −1 at a current density of 100 mA g −1 after 200 cycles, and it still depicts a good long-term cycling durability, maintaining 739 mAh g −1 at a current density of 400 mA g −1 after 400 cycles.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源存储
·
功能材料
·
锂离子电池
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2021
·Vol. 64
·期 6
·1378-1385
·
IF 8.273
Fu Yuanyuan,Ma Cheng
The interplay between solid electrolytes and electrodes is of vital importance to the performance of all-solid-state Li batteries. Recently, halide superionic conductors have emerged as a new family of high-performance solid electrolytes, but their compatibility with Li metal, i.e., the anode with the highest theoretical capacity, has not been systematically studied. Here, we investigate the interaction between Li metal and two representative halide solid electrolytes: Li 3 YCl 6 and Li 3 YBr 6 . Both materials are found to form interphases with Li, similar to most solid electrolytes. However, the interphases observed here contain electronic conducting components, which are detrimental to their compatibility with Li. By elucidating this phenomenon, the present study provides guiding principles for improving the Li compatibility of halide solid electrolytes.
研究领域:
材料科学
·
电化学
·
固态离子学
·
能源存储
·
电池技术
✓ 已验证
DOI
高影响因子
SOLID STATE IONICS
·
2016
·
IF 2.38
Shanshan Mo,Penghao Lu,Fei Ding,Zhibin Xu,Jiaquan Liu,Xingjiang Liu,Qiang Xu
Sulfide glasses with a high lithium-ion conductivity are promising solid electrolyte for all-solid-state lithium-ion batteries. In this study, 95(0.7Li 2 S–0.3P 2 S 5 )–5Li 3 PO 4 glass electrolyte is prepared by mixing 70Li 2 S-30P 2 S 5 (mol%) glass and Li 3 PO 4 crystal using mechanical milling technique. The effects on the structures and electrochemical properties of the obtained ternary sulfide glass were examined. The ternary sulfide glass shows a good electrochemical stability, which may exhibit a wide electrochemical window up to 10 V (vs. Li/Li + ). Furthermore, the 95(0.7Li 2 S-0.3P 2 S 5 )-5Li 3 PO 4 glass electrolyte displays an electrical conductivity of 2.513 × 10 − 3 S cm − 1 at 100 °C. The all-solid-state lithium-ion cell assembled with 95(0.7Li 2 S-0.3P 2 S 5 )-5Li 3 PO 4 glass electrolyte shows a favourable cyclability, which can reveal a discharge capacity of 144 mAh g − 1 at 0.05 °C and a discharge capacity of 63.9 mAh g − 1 at 0.1C after the 50th cycle at 100 °C, respectively.
研究领域:
材料科学
·
电化学
·
能源存储
·
固态离子学
·
锂电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 30
·期 2
·1699-1705
·
IF 2.324
Teng Fei,Chen Dong,Ma Yuzhe,Ji Shaohua,Liu Jiaojiao,Wang Tianhua,Tang Jie,Cao Lifeng,Teng Bing
N,N -dimethylamino-4′-N′-methylstilbazolium 2,4,6-trimethylbenzenesulfonate (DSTMS)-graphene ex-situ and in-situ composite films with 2% concentration of graphene were first prepared and systematically investigated. The crystallinity of DSTMS-based composite films were confirmed by XRD analysis, and the functional groups of composite films can be obtained by FT-IR. Optical absorptions were recorded using UV–Vis-NIR spectral analysis, and the band gap and extinction coefficient of the films were calculated. The thermal stability of the composite films were analyzed by TG/DSC. The pressure sensitive resistance test showed that the pressure sensitive signal of the composite films were significantly increased after graphene added, while the signal of DSTMS film eventually disappears. This work expands the application of organic nonlinear crystal DSTMS in optics and electricity by doping graphene.
研究领域:
材料科学
·
凝聚态物理
·
功能材料
·
非线性光学
·
纳米复合材料
·
电学性能
·
光学性能
·
热分析
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2022
·
IF 6.206
Shuming Liu,Shuqi Liu,Qian Wang,Zhou Zuo,Xidong Liang
Superhydrophobic surfaces, such as lotus leaves, have attracted significant attention because of their excellent performance and potential application value. However, the micro-nano hierarchy on superhydrophobic surfaces is often vulnerable and easily broken from mechanical stress or chemical corrosion, which greatly inhibits its practical application and long-term service. This study presents a low-cost and scalable superhydrophobic coating based on an interpenetrated polymer network of polydimethylsiloxane (PDMS) and epoxy resin . The composite polymer matrix exhibits mechanical robustness as derived from the epoxy resin and low surface energy as derived from the PDMS. The superhydrophobic coating is obtained by dispersing fluoroalkyl-silane-modified SiO 2 in the solution containing the composite polymer . The multi-level hierarchical structure of SiO 2 aggregations and their strong bonding with the composite polymer gives the coating outstanding mechanical durability while maintaining superhydrophobicity after multiple cycles of sandpaper abrasion, tape peeling, and water impact tests. The chemical inertness of all components ensures its chemical stability, and the surface shows super repellency to strong acids and alkaline liquids (pH = 0–14). The coating also has excellent self-cleaning properties, which has potential applications in various industrial fields.
研究领域:
材料科学
·
高分子化学
·
表面工程
·
涂层技术
·
功能材料
✓ 已验证
DOI
高影响因子
IONICS
·
2016
·Vol. 23
·期 10
·2603-2611
·
IF 2.119
Chen Shaojie,Zhao Yanran,Yang Jing,Yao Lili,Xu Xiaoxiong
Three types of inorganic electrolytes [Li 10 GeP 2 S 12 (LGPS), 75Li 2 S·24P 2 S 5 ·1P 2 O 5 (LPOS), Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 (LAGP)] with different particle sizes and electrochemical properties are selected as active fillers incorporated into poly(ethylene oxide) (PEO) matrix to fabricate hybrid solid electrolytes. The optimum composition of each filler is found in consideration of ionic conductivity. Their electrochemical characteristics are investigated. The optimal conductivities are 1.60 × 10 −5 , 1.18 × 10 −5 , and 2.12 × 10 −5 S cm −1 at room temperature for PEO-1%LGPS, PEO-1%LPOS, and PEO-20%LAGP, respectively. The electrochemical stability windows of these hybrid solid electrolytes are all above 5 V (vs. Li + /Li). The results show that these fillers have positive effects on the ionic conductivity, lithium ion transference number, and electrochemical stability. The relationship between the type of filler and electrochemical properties has been investigated. All-solid-state cells LiFePO 4 /Li are fabricated and present fascinating electrochemical performance with high capacity retention and good cycling stability. This work provides promising electrolytes prepared by a simple method.
研究领域:
材料科学
·
电化学
·
能源存储
·
固态离子学
·
功能材料
·
锂电池技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yu Liu,Meng Huang,Fangyu Xiong,Jiexin Zhu,Qinyou An
Zinc-ion batteries (ZIBs) using zinc metal as anode materials suffer from Zn dendrite formation and hydrogen evolution during the stripping/plating process, which will lead to performance degradation and hinder practical application. Herein, the 1,4,5,8-naphthalene diimide (NI) is proposed as a promising dendrite-free organic anode material for ZIBs . Moreover, the effect of different binders on electrochemical performance of NI electrode is investigated. Compared NI electrode with polyvinylidene fluoride (PVDF) binder, the NI electrode with the polytetrafluoroethylene (PTFE) binder shows highly enhanced rate capability (122.2 mA h g – 1 at 5 A g – 1 ) and cycling performance (123.3 mA h g – 1 at 3 A g – 1 after 2200 cycles). The improvement cycling stability of NI is attributed to PTFE binder, which effectively maintains electrode structure and inhibits dissolution of organic molecules during the cycling process. In addition, the ion kinetics analyses reveal that the superior rate capability is provided by the capacitive charge storage. And the carbonyl group of NI is active center of electrochemistry, which is revealed by in-situ attenuated total reflection–Fourier transform infrared (ATR-FTIR) and ex-situ Raman. Besides, the aqueous Zn-ion full cell based on metal-free NI anode and Prussian blue analogues (PBAs) cathode exhibits excellent rate capability (113.9 mA h g – 1 at 10.0 A g – 1 ), high operation voltage of ~ 1.2 V (at 1.0 A g – 1 ) and energy density of 50.2 Wh kg total – 1 . This work may provide a new design inspiration to develop organic dendrite-free zinc anodes for high-performance aqueous ZIBs batteries.
研究领域:
电化学
·
能源材料
·
电池技术
·
功能材料
·
应用化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Xiao-Qian Wei,Wan-Ju Zhang,Lu Lai,Ping Mei,Li-Mei Wu,Yan-Qun Wang
The effects of cationic surfactants on the properties of Pickering emulsions stabilized by silica nanoparticles (nano-SiO 2 ) were investigated. The zeta potential , three-phase contact angle ( θ ), and dynamic interfacial tension (DIT) were measured to analyze the interaction between hydrophilic nano-SiO 2 and four different cationic surfactants (i.e., dodecyltrimethylammonium bromide [DTAB], bis-quaternary ammonium salts [BQAS-12], multiple quaternary ammonium salts [MQAS-12], and dimethyldioctadecylammonium bromide [DDAB-18]). All these surfactants can naturally improve the stability of Pickering emulsions induced by hydrophilic nano-SiO 2 . The nano-SiO 2 /MQAS-12 mixtures exhibited the best ability to stabilize the O/W emulsions, followed by nano-SiO 2 /BQAS-12 mixtures. The nano-SiO 2 /DDAB-18 mixtures can induce emulsion inversion from O/W to W/O. All emulsions exhibited excellent salt tolerance and acid-base resistance properties. Determining the zeta potential showed that nano-SiO 2 had the highest negative charge at the pH of 9.5. Thus, the surfactant molecules can be adsorbed remarkably on the nano-SiO 2 surface. Modification with different cationic surfactants can significantly increase the θ value of nano-SiO 2 , but the bilayers for DTAB-12, BQAS-12, and MQAS-12, except for DDAB-18, were adsorbed. DIT curves indicated that competitive adsorption of the surfactants occurred between the oil/water interface and nano-SiO 2 surface. The competitive adsorption of MQAS-12 was stronger than those of BQAS-12 and DTAB-12. The nano-SiO 2 /DDAB-18 mixture had an apparent induction region and required a considerable amount of time to reach equilibrium. The modified nano-SiO 2 was also not adsorbed in the oil/water interface spontaneously, which may be due to the large size of particles compared with small surfactant molecules.
研究领域:
胶体与界面化学
·
纳米材料科学
·
乳液工程
·
物理化学
·
表面科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
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
·
能源材料
·
纳米材料
·
界面化学
·
储能技术
·
先进电池
·
功能高分子
·
柔性电子
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·Vol. 47
·期 16
·22776-22785
·
IF 4.527
Kaidan Wu,Yefeng Feng,Jin Ke,Bingwen Yang,Zhiling Guo,Deping Xiong,Miao He
Graphite nanosheets coated by LiF/SnO 2 composites are designed to obtain a lithium ion anode material with excellent performance. LiF nanoparticles play a significant role in improving the electrochemical performance by inhibiting electrolyte decomposition and providing excess Li sources during cycling. The obtained LiF@SnO 2 @C electrode shows an outstanding capacity of 951.9 mAhg −1 at 0.2 Ag -1 after 370 cycles and excellent long cycling performance of 650.0 mAhg −1 at 1.0 Ag -1 after 930 cycles. First-principles calculations demonstrate that F-doped SnO 2 (−2211.8 eV) has a lower free energy compared to SnO 2 (−1937.4 eV), resulting in a robust composite architecture that gives rise to high cycling stability.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
计算材料学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）