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991.
Yuxiao Wang Ying Yu Yeqiang Tan Tianyu Li Yanbing Chen Shuang Wang Kunyan Sui Hongzhang Zhang Yang Luo Xianfeng Li 《Liver Transplantation》2020,10(2)
Lithium–sulfur (Li–S) batteries are promising candidates for energy storage, but suffer from capacity and cycling challenges caused by the serious shuttling effect of polysulfide (PS) ions. To address these issues, a sodium alginate (SA)‐derived affinity laminated chromatography membrane built‐in electrode is designed. This is the first attempt to utilize this type of membrane, which is widely used for the selective adsorption of proteins, in the battery field. An ordered multilayer structure throughout the electrode can easily be obtained, and the number of membrane layers can be also conveniently controlled by varying the cross‐linking time of SA. The PS shuttling effect is efficiently suppressed and the permeability of PSs is reduced by enveloping the carbon/sulfur powder in ultrathin laminated chromatography membranes. As a result, these designed electrodes deliver a superhigh initial capacity of 1492 mA h g?1, with a capacity retention almost 20% higher than the contrast. This low‐cost and easily mass‐producible strategy inspired by affinity chromatography is expected to effectively solve the PS shuttling problem toward high‐loading and long‐lifetime Li–S batteries in practice. 相似文献
992.
993.
994.
Changzhi Sun Aming Lin Wenwen Li Jun Jin Yiyang Sun Jianhua Yang Zhaoyin Wen 《Liver Transplantation》2020,10(3)
The introduction of 3D wettable current collectors is one of the practical strategies toward realizing high reversibility of lithium (Li) metal anodes, yet its effect is usually insufficient owing to single electron‐conductive skeleton. Here, homogeneous Li deposition behavior and enhanced Coulombic efficiency is reported for electrochemically lithiated Cu3P nanowires, owing to the formation of a mixed ion/electron‐conducting skeleton (MIECS). In particular, by evaluating the Gibbs free energy change, the possible chemical reaction between Cu3P and molten Li is used to construct a MIECS containing Li3P and Cu–Li alloy phase. The successful conversion of Cu3P nanowires to Li3P and Cu–Li alloy nanocomposite not only greatly reduces the surface energy between molten Li and Cu3P, but also induces uniform Li stripping/plating behavior via balanced ion/electron transport. Thus, the as‐obtained Li@MIECS composite anode displays superior cycling stability in both symmetric cells and full cells. This work provides a promising option for the preparation of high‐performance composite Li anodes containing MIECS by thermally pre‐storing Li. 相似文献
995.
Zhongkai Hao Qi Chen Wenrui Dai Yinjuan Ren Yin Zhou Jinlin Yang Sijie Xie Yanbin Shen Jihong Wu Wei Chen Guo Qin Xu 《Liver Transplantation》2020,10(10)
Developing a titanium dioxide (TiO2)‐based anode with superior high‐rate capability and long‐term cycling stability is important for efficient energy storage. Herein, a simple one‐step approach for fabricating blue TiO2 nanoparticles with oxygen vacancies is reported. Oxygen vacancies can enlarge lattice spaces, lower charge transfer resistance, and provide more active sites in TiO2 lattices. As a result, this blue TiO2 electrode exhibits a highly reversible capacity of 50 mAh g?1 at 100 C (16 800 mA g?1) even after 10 000 cycles, which is attributable to the combination of surface capacitive process and remarkable diffusion‐controlled insertion revealed by the kinetic analysis. The strategy of employing oxygen‐deficient nanoparticles may be extended to the design of other robust semiconductor materials as electrodes for energy storage. 相似文献
996.
Lu Wan Cuili Zhang Kunpeng Ge Xueliang Yang Feng Li Wensheng Yan Zhuo Xu Lin Yang Ying Xu Dengyuan Song Jianhui Chen 《Liver Transplantation》2020,10(16)
Defect state passivation and conductivity of materials are always in opposition; thus, it is unlikely for one material to possess both excellent carrier transport and defect state passivation simultaneously. As a result, the use of partial passivation and local contact strategies are required for silicon solar cells, which leads to fabrication processes with technical complexities. Thus, one material that possesses both a good passivation and conductivity is highly desirable in silicon photovoltaic (PV) cells. In this work, a passivation‐conductivity phase‐like diagram is presented and a conductive‐passivating‐carrier‐selective contact is achieved using PEDOT:Nafion composite thin films. A power conversion efficiency of 18.8% is reported for an industrial multicrystalline silicon solar cell with a back PEDOT:Nafion contact, demonstrating a solution‐processed organic passivating contact concept. This concept has the potential advantages of omitting the use of conventional dielectric passivation materials deposited by costly high‐vacuum equipment, energy‐intensive high‐temperature processes, and complex laser opening steps. This work also contributes an effective back‐surface field scheme and a new hole‐selective contact for p‐type and n‐type silicon solar cells, respectively, both for research purposes and as a low‐cost surface engineering strategy for future Si‐based PV technologies. 相似文献
997.
Hong Duc Pham Terry Chien‐Jen Yang Sagar M. Jain Gregory J. Wilson Prashant Sonar 《Liver Transplantation》2020,10(13)
There has been considerable progress over the last decade in development of the perovskite solar cells (PSCs), with reported performances now surpassing 25.2% power conversion efficiency. Both long‐term stability and component costs of PSCs remain to be addressed by the research community, using hole transporting materials (HTMs) such as 2,2′,7,7′‐tetrakis(N,N′‐di‐pmethoxyphenylamino)‐9,9′‐spirbiuorene(Spiro‐OMeTAD) and poly[bis(4‐phenyl)(2,4,6‐trimethylphenyl)amine] (PTAA). HTMs are essential for high‐performance PSC devices. Although effective, these materials require a relatively high degree of doping with additives to improve charge mobility and interlayer/substrate compatibility, introducing doping‐induced stability issues with these HTMs, and further, additional costs and experimental complexity associated with using these doped materials. This article reviews dopant‐free organic HTMs for PSCs, outlining reports of structures with promising properties toward achieving low‐cost, effective, and scalable materials for devices with long‐term stability. It summarizes recent literature reports on non‐doped, alternative, and more stable HTMs used in PSCs as essential components for high‐efficiency cells, categorizing HTMs as reported for different PSC architectures in addition to use of dopant‐free small molecular and polymeric HTMs. Finally, an outlook and critical assessment of dopant‐free organic HTMs toward commercial application and insight into the development of stable PSC devices is provided. 相似文献
998.
Xinliang Li Mian Li Qi Yang Guojin Liang Zhaodong Huang Longtao Ma Donghong Wang Funian Mo Binbin Dong Qing Huang Chunyi Zhi 《Liver Transplantation》2020,10(36)
The traditional method to fabricate a MXene based energy storage device starts from etching MAX phase particles with dangerous acid/alkali etchants to MXenes, followed by device assembly. This is a multistep protocol and is not environmentally friendly. Herein, an all‐in‐one protocol is proposed to integrate synthesis and battery fabrication of MXene. By choosing a special F‐rich electrolyte, MAX V2AlC is directly exfoliated inside a battery and the obtained V2CTX MXene is in situ used to achieve an excellent battery performance. This is a one‐step process with all reactions inside the cell, avoiding any contamination to external environments. Through the lifetime, the device experiences three stages of exfoliation, electrode oxidation, and redox of V2O5. While the electrode is changing, the device can always be used as a battery and the performance is continuously enhanced. The resulting aqueous zinc ion battery achieves outstanding cycling stability (4000 cycles) and rate performance (97.5 mAh g?1 at 64 A g?1), distinct from all reported aqueous MXene‐based counterparts with pseudo‐capacitive properties, and outperforming most vanadium‐based zinc ion batteries with high capacity. This work sheds light on the green synthesis of MXenes, provides an all‐in‐one protocol for MXene devices, and extends MXenes’ application in the aqueous energy storage field. 相似文献
999.
Hoon‐Hee Ryu Nam‐Yung Park Dae Ro Yoon Un‐Hyuck Kim Chong S. Yoon Yang‐Kook Sun 《Liver Transplantation》2020,10(25)
A new class of layered cathodes, Li[NixCoyB1?x?y]O2 (NCB), is synthesized. The proposed NCB cathodes have a unique microstructure in which elongated primary particles are tightly packed into spherical secondary particles. The cathodes also exhibit a strong crystallographic texture in which the a–b layer planes are aligned along the radial direction, facilitating Li migration. The microstructure, which effectively suppresses the formation of microcracks, improves the cycling stability of the NCB cathodes. The NCB cathode with 1.5 mol% B delivers a discharge capacity of 234 mAh g?1 at 0.1 C and retains 91.2% of its initial capacity after 100 cycles (compared to values of 229 mAh g?1 at 0.1 C and 78.8% for pristine Li[Ni0.9Co0.1]O2). This study shows the importance of controlling the microstructure to obtain the required cycling stability, especially for Ni‐rich layered cathodes, where the main cause of capacity fading is related to mechanical strain in their charged state. 相似文献
1000.
Qiangjian Ju Ruguang Ma Yu Pei Beibei Guo Zichuang Li Qian Liu Tiju Thomas Minghui Yang Graham J. Hutchings Jiacheng Wang 《Liver Transplantation》2020,10(21)
The development of Pt‐free catalysts for the alkaline hydrogen evolution reaction (HER), which is widely used in industrial scale water‐alkali electrolyzers, remains a contemporary and pressing challenge. Ruthenium (Ru) has excellent water‐dissociation abilities and could be an alternative water splitting catalyst. However, its large hydrogen binding energy limits HER activity. Here, a new approach is proposed to boost the HER activity of Ru through uniform loading of Ru nanoparticles on triazine‐ring (C3N3)‐doped carbon (triNC). The composite (Ru/triNC) exhibits outstanding HER activity with an ultralow overpotential of ≈2 mV at 10 mA cm?2; thereby making it the best performing electrocatalyst hitherto reported for alkaline HER. The calculated metal mass activity of Ru/triNC is >10 and 15 times higher than that of Pt/C and Pt/triNC. Both theoretical and experimental studies reveal that the triazine‐ring is a good match for Ru to weaken the hydrogen binding on Ru through interfacial charge transfer via increased contact electrification. Therefore, Ru/triNC can provide the optimal hydrogen adsorption free energy (approaching zero), while maintaining the strong water‐dissociation activity. This study provides a new avenue for designing highly efficient and stable electrocatalysts for water splitting. 相似文献