Small Methods
·
2024
·Vol. 8
·期 7
·2301233
·
IF 10.7
Xiaolin Ye,Ningxin Xiong,Shaopei Huang,Qixing Wu,Hongning Chen,Xuelong Zhou
Tin-based hybrid flow batteries have demonstrated dendrite-free morphology and superior performance in terms of cycle life and energy density. However, the quick accumulation of electrodeposits near the electrode/membrane interface blocks the ion transport pathway during the charging of the battery, resulting to a very limited areal capacity (especially at high current density) that significantly hinders its deployment in long-duration storage applications. Herein, a conductivity-activity dual-gradient design is disclosed by electrically passivating the carbon felt near the membrane/electrode interface and chemically activating the carbon felt near the electrode/current collector interface. In consequence, the tin metals are preferentially plated at the region near electrode/current collector, preventing the ion transport pathway from being easily blocked. The resultant gradient electrode demonstrated an unprecedentedly high areal capacity of 268 mAh cm −2 at a current density of as high as 80 mA cm −2 . Numerical modeling and experimental characterizations show that the dual-gradient electrode differs from conventional electrodes with regard to their reaction current density distribution and electrodeposit distribution during charging. This work demonstrates a new design strategy of 3D electrodes for hybrid flow batteries to induce a desirable distribution of electrodeposits and achieve a high areal capacity at commercially relevant current densities.
研究领域:
电化学储能
·
材料科学
·
能源化学
·
电池技术
·
功能材料
·
电化学工程
✓ 已验证
DOI
高影响因子
Small
·
2019
·Vol. 15
·期 30
·1902280
·
IF 10.856
Xijun Wei,Wanping Hu,Huarong Peng,Yuli Xiong,Peng Xiao,Yunhuai Zhang,Guozhong Cao
High energy and efficient solar charging stations using electrochemical capacitors (ECs) are a promising portable power source for the future. In this work, two kinds of metal-organic framework (MOF) derivatives, NiO/Co 3 O 4 microcubes and Fe 2 O 3 microleaves, are prepared via thermal treatment and assembled into electrochemical capacitors, which deliver a relatively high specific energy density of 46 Wh kg −1 at 690 W kg −1 . In addition, a solar-charging power system consisting of the electrochemical capacitors and monocrystalline silicon plates is fabricated and a motor fan or 25 LEDs for 5 and 30 min, respectively, is powered. This work not only adds two novel materials to the growing categories of MOF-derived advanced materials, but also successfully achieves an efficient solar-ECs system for the first time based on all MOF derivatives, which has a certain reference for developing efficient solar-charge systems.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
可再生能源
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2023
·Vol. 66
·期 5
·1810-1819
·
IF 8.1
Xiao Hongbin,Qian Qingkai,Zang Zhigang
Recently, all-inorganic cesium lead halide (CsPbX 3 (X = Cl, Br, and I) perovskite nanocrystals (NCs) have been extensively investigated for photocatalytic carbon dioxide (CO 2 ) reduction reaction (CO 2 RR). However, because the pristine CsPbX 3 NCs suffer from severe radiative recombination, it is imperative to elaborately design heterostructures to separate electron-hole pairs for achieving efficient CO 2 RR. Herein, palladium (Pd) nanoparticles (NPs) are anchored on CsPbBr 3 NCs by a photo-assisted approach for the first time. The as-prepared CsPbBr 3 @Pd NCs not only build Schottky junctions at the CsPbBr 3 /Pd interfaces that promote the carrier separation and suppress the radiative recombination, but also exhibit lower energy barriers for photocatalytic CO 2 RR than pristine CsPbBr 3 NCs according to the density functional theory calculations. The electron consumption rate reaches a striking peak of 46.2 µmol g −1 h −1 by using CsPbBr 3 @Pd NCs as photocatalysts for CO 2 RR, which is 4.8-fold of the counterpart of pristine CsPbBr 3 NCs. This work not only presents a photo-assisted strategy for anchoring Pd NPs on CsPbBr 3 NCs, but also demonstrates the great potential of using CsPbBr 3 @Pd NCs for photocatalytic CO 2 RR.
研究领域:
材料化学
·
光催化
·
纳米材料
·
环境化学
·
能源化学
·
半导体物理
·
催化化学
✓ 已验证
DOI
高影响因子
Materials Today Physics
·
2022
·
IF 11.021
Zilin Ruan,Jianchen Lu,Baijin Li,Qizan Chen,Zhenliang Hao,Lei Gao,Jinming Cai
Structural defects in two-dimensional materials offer an effective way to engineer their functionalities. In-situ local measurements to build the structure-function relationship are crucial for future device technology. Here, we present a comprehensive study of intrinsic defects in single-layer WS 2 grown by chemical vapor deposition using a combination of scanning tunneling microscopy/spectroscopy, non-contact atomic force microscopy and density functional theory calculations. We probed the rarely observed positively charged defects and the intersection of adjacent charging rings at sufficiently high bias caused by subsurface defects. We also directly identified and visualized the widely observed negatively charged defects as chalcogen vacancies-related defects. The results reported here will guide future efforts of targeted defect engineering and doping of the single-layer transition metal dichalcogenides .
研究领域:
材料科学
·
凝聚态物理
·
纳米科技
·
表面科学
·
二维材料
·
半导体物理
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 4
·5841-5851
·
IF 3.741
Zhi Ming Wang,Peng Liu,Yan Peng Cao,Feng Ye,Chao Xu,Xiao Ze Du
Summary In this study, novel Pt-IrO 2 nanofiber catalysts for oxygen evolution reaction (OER) were successfully prepared using the electrospinning method with a high-concentration precursor solution. The composition and structure of catalysts were characterized, and the electrocatalytic performance of the nanofiber catalysts in water electrolysis was investigated from various aspects such as overpotential, charge transfer resistance, and exchange current density. Special attention was paid on the effect of Pt/Ir ratio on the electrocatalytic activity of the electrospun nanofibers. The results showed that the Pt-IrO 2 nanofiber catalysts with average fiber diameters ranging from 10 to 100 nm can be successfully obtained by the electrospinning method, and the average diameter decreased with the increase of Pt content. Since a bigger amount of IrO 2 content and a thinner fiber structure are all beneficial to the electrocatalytic performance, the Pt-IrO 2 catalysts with Pt:Ir = 1:9 and Pt:Ir = 9:1 both showed better catalytic performance for OER than the commercial IrO 2 , which was also demonstrated by the lower charge transfer resistance and higher exchange current density. As a result, the overpotentials of Pt-IrO 2 catalysts with Pt:Ir = 1:9 and Pt:Ir = 9:1 are 50 mV and 32 mV lower than the overpotential of the commercial IrO 2 at 30 mA cm −2 in 0.5 M H 2 SO 4 , respectively. The electrospun Pt-IrO 2 nanofiber catalyst with proper Pt content seems to be very promising since it can not only improve the catalytic performance and the safety of PEM electrolysis cells, but also reduce the amount of more expensive Ir in catalysts.
研究领域:
材料科学
·
电化学
·
纳米材料
·
能源化学
·
催化化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2016
·
IF 4.803
Na Li,ChunYi Zhi,Haiyan Zhang
The preparation of high specific-capacity pseudocapacitive transition-metal-oxide/hydroxide (TMH) materials into transparent micro-structure electrodes is a great challenge and has become the bottleneck restricting the performance of transparent flexible supercapacitors . Beyond that, extending the operating voltage window is an urgent need for improving energy density . Here, Co(OH) 2 nanosheets and amorphous FeOOH nanowires were prepared into transparent films through a simple and scalable bio-inspired method at the air-solution interface. Both nanostructures are enwrapped in graphene shells (Co@Gr-TFandFe@Gr-TF) for use as transparent asymmetric pseudocapacitive electrodes. The unique encapsulation structures (1) provide pseudocapacitive electrode materials, especially an amorphous FeOOH structure cathode, (2) build up rapid three-dimensional electron and ion transport pathways together with the underlying ITO layer, (3) alleviate the exfoliation and dissolution of the active materials into electrolyte, and (4) extend the potential window of the FeOOH cathode from −0.8 ∼ 0 V to −1.2 ∼ 0 V with minimal cycling stability degradation. The asymmetric transparent and flexible supercapacitor based on Co@Gr-TF//Fe@Gr-TF operated at 1.8 V exhibits good transparency (50.5% at 550 nm), high specific capacitance (25.5 mF cm −2 , one order higher than the maximum value reported for FFT-GP), and high energy density (1.04 mWh cm −3 , comparable to that of nontransparent devices) as well as a long cycle life (10 000 cycles) with high-capacity retention (83.5%).
研究领域:
材料科学
·
纳米科技
·
电化学
·
能源存储
·
柔性电子学
·
功能薄膜
✓ 已验证
DOI
高影响因子
RARE METALS
·
2019
·Vol. 38
·期 6
·588-600
·
IF 1.785
Huang Lei,Su Kun,Zheng Yu-Feng,Yeung Kelvin Wai-Kwok,Liu Xiang-Mei
A TiO 2 nanofilm was prepared on the surface of AZ31 magnesium alloy with controllable thickness through atomic layer deposition (ALD) technique, which can adjust the corrosion behaviors of AZ31 Mg alloy. Compared with the untreated Mg alloys, corrosion current densities ( i corr ) can decline by 58% in the 200-cycles TiO 2 -covered Mg alloy and further decline by up to 74% with the thickness of nanofilm up to 63 nm (400 cycles). The subsequent modification with a cross-linked conversion layer of 3-amino-propyltriethoxysilane (APTES) by a dipping method can produce a compact silane coating on TiO 2 nanofilm, which can seal pinholes of TiO 2 nanofilm and serve as a barrier to further adjust the corrosion behavior of the substrate. The i corr can decline about two orders of magnitude in the TiO 2 /silane composite coating. Making the adjustable corrosion rate come true, which can be attributed to the precise control on the thickness of metal oxide nanofilm and additional protection from the compact silane coating. In vitro study discloses that the TiO 2 /silane hybrid coating shows higher expression of alkaline phosphatase (ALP) and can promote cellular adhesion and proliferation with better cytocompatibility than untreated Mg alloy.
研究领域:
材料科学
·
生物医学工程
·
腐蚀科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2018
·
IF 5.158
Ningxiao Yuan,Lu Xu,Bo Xu,Jianhao Zhao,Jianhua Rong
Chitosan derivative-based self-healable hydrogels with enhanced mechanical properties are reported, which were prepared by polymerization of acrylic acid (AAc) in 2-hydroxypropyltrimethyl ammonium chloride chitosan (HACC) solution. The PAAc/HACC hydrogels exhibit tensile fracture stress as high as 3.31 MPa and a Young's modulus of 2.53 MPa. They can maintain their original shape after 30 repeated compression cycles under various strain conditions, with a compression stress of more than 60 MPa at 99% strain. The damaged PAAc/HACC hydrogels can heal together in the presence of a NaCl salt solution with a self-healing efficiency of up to 61%. In addition, the PAAc/HACC hydrogels have high ionic conductivity and can serve as electrolytes for supercapacitors. The analysis suggests that all these good properties of the PAAc/HACC hydrogels mainly result from their high-density dynamic ionic interactions structure.
研究领域:
高分子材料科学
·
生物医学工程
·
功能材料
·
组织工程
·
药物递送系统
·
再生医学
·
电化学器件
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2016
·Vol. 18
·期 29
·19731-19737
·
IF 4.449
Yingna Cui,Jingmei Yin,Changping Li,Shenmin Li,Ailing Wang,Guang Yang,Yingping Jia
The compositions and structures of amine-based functionalized protic ionic liquids (PILs), namely N,N-dimethyl(cyanoethyl)ammonium propionate (DMCEAP) and N,N-dimethyl(hydroxyethyl)ammonium propionate (DMEOAP) have been investigated systematically by IR and 1H NMR spectroscopy and density functional theory (DFT) calculations. Analysis of the IR spectra suggests that both DMCEAP and DMEOAP are composed of neutral and ionized species in the liquid phase, the former one mainly existing in the state of precursor molecules, and the latter mainly as ion-pairs. The ratio of precursor molecules to ion-pairs in the liquid phase depends on the types of precursors, especially the functional groups of cations. 1H NMR spectra indicate that there is a dynamic equilibrium between the neutral and ionized species, probably due to the formation of some intermediates in the PILs. The DFT calculations have been carried out to reveal the conformation, and obtain the corresponding IR and 1H NMR spectra of the neutral and ionized species, so that the theoretical support to the experimental results can be provided. The present study will help understand the properties of PILs and provide guidance for further applications of PILs.
研究领域:
物理化学
·
离子液体化学
·
光谱学
·
理论化学
·
分析化学
·
材料化学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·Vol. 11
·期 3
·110269
·
IF 7.7
Jinghua Li,Haofeng Zhu,Dandi Fang,Xusheng Huang,Chaoqun Zhang,Ying Luo
Although the recycling and reuse of polyurethane foam (PUF) is a promising route to deal with this type of waste commodity polymer, highly efficient and green processing protocols are a great challenge due to their stable crosslink structure. In this study, a strategy of urethane exchange reactions was proposed to transform commercial rigid PUF into PUF sheets. The process was composed of the pulverization of the foam, the pretreatment method and the hot pressing. The effects of the pretreatment method on the structure and properties of the recycled commercial PUF were studied. The results show that the ball milling pretreatment method can effectively pulverize the commercial PUF into powder of 74.5 µm and a specific surface area as high as 2991.0 m 2 /kg, which can promote the urethane exchange reaction in close contact with the catalyst. The recycle method of ball milling pretreatment makes the crosslink density and tensile strength of the PUF sheets reach 2236.8 mol/m 3 and 32.6 MPa, which means an increase of 9.9 times and 3.3 times, respectively, compared to the method of other pretreatment. Moreover, PUF sheets can still maintain 71.5% of the tensile strength after two cycles of recycling, indicating the potential of this recycling method for PUF. This simple and efficient method enhances the sustainability of rigid PUF utilization and shows the enormous potential for value-added recycling of thermosets .
研究领域:
高分子材料科学
·
环境科学与工程
·
绿色化学
·
资源循环利用
·
材料再生
·
可持续材料技术
·
功能高分子
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）