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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
971.
972.
Jung‐Gu Han Chihyun Hwang Su Hwan Kim Chanhyun Park Jonghak Kim Gwan Yeong Jung Kyungeun Baek Sujong Chae Seok Ju Kang Jaephil Cho Sang Kyu Kwak Hyun‐Kon Song Nam‐Soon Choi 《Liver Transplantation》2020,10(20)
High‐capacity Li‐rich layered oxide cathodes along with Si‐incorporated graphite anodes have high reversible capacity, outperforming the electrode materials used in existing commercial products. Hence, they are potential candidates for the development of high‐energy‐density lithium‐ion batteries (LIBs). However, structural degradation induced by loss of interfacial stability is a roadblock to their practical use. Here, the use of malonic acid‐decorated fullerene (MA‐C60) with superoxide dismutase activity and water scavenging capability as an electrolyte additive to overcome the structural instability of high‐capacity electrodes that hampers the battery quality is reported. Deactivation of PF5 by water scavenging leads to the long‐term stability of the interfacial structures of electrodes. Moreover, an MA‐C60‐added electrolyte deactivates the reactive oxygen species and constructs an electrochemically robust cathode‐electrolyte interface for Li‐rich cathodes. This work paves the way for new possibilities in the design of electrolyte additives by eliminating undesirable reactive substances and tuning the interfacial structures of high‐capacity electrodes in LIBs. 相似文献
973.
Qiang Li Qizhao Wang Linlin Li Lijun Yang Yang Wang Xiaohui Wang Hai‐Tao Fang 《Liver Transplantation》2020,10(24)
The capacitance of microsupercapacitors (MSCs) can double if both sides of substrates are used to construct MSCs. Nevertheless, achieving electric connections of MSCs through substrates is a challenge due to the difficulty in precisely positioning each MSC couple that has two of the same MSCs units on two sides. In this work, taking advantage of the synchronous etching on both sides of transparent polyethylene terephthalate substrates by femtosecond laser pulses, a double‐sided configuration is attained with high precision in the alignment of back‐to‐back MSC couples and versatile double‐side MSCs are realized via arbitrary on‐ and through‐substrate connections of MXene MSC units. The MXene double‐side MSC fabricated by the series connection of 12 spiral pattern MXene MSC units with interdigital electrodes of 10 μm width interspace can output a large working voltage of 7.2 V. Additionally, femtosecond laser etching brings the transformation of MXene into titania near‐etched edges with a lateral distance less than 1 µm. Such a small laser‐affected area has little influence on the capacitive performance, which is one of advantages for femtosecond laser over conventional lasers. This research is valuable for one‐step manufacturing of highly integrated MSCs in the field of miniaturized energy storage systems. 相似文献
974.
Mickaël Mateos Nikolina Makivic Yee‐Seul Kim Benoît Limoges Vronique Balland 《Liver Transplantation》2020,10(23)
Rechargeable batteries based on MnO2 cathodes, able to operate in mild aqueous electrolytes, have attracted attention due to their appealing features for the design of low‐cost stationary energy storage devices. However, the charge/discharge mechanism of MnO2 in such media is still a matter of debate. Here, an in‐depth quantitative spectroelectrochemical analysis of MnO2 thin‐films provides a set of unrivaled mechanistic insights. A major finding is that charge storage occurs through the reversible two‐electron faradaic conversion of MnO2 into Mn2+ in the presence of a wide range of weak Brønsted acids, including the [Zn(H2O)6]2+ or [Mn(H2O)6]2+ complexes present in aqueous Zn/MnO2 batteries. Furthermore, it is shown that buffered electrolytes loaded with Mn2+ are ideal to achieve highly reversible conversion of MnO2 with both high gravimetric capacity and remarkably stable charging/discharging potentials. In the most favorable case, a record gravimetric capacity of 450 mA·h·g?1 is obtained at a high rate of 1.6 A·g?1, with a Coulombic efficiency close to 100% and a MnO2 utilization of 84%. Overall, the present results challenge the common view on MnO2 the charge storage mechanism in mild aqueous electrolytes and underline the benefit of buffered electrolytes for high‐performance rechargeable aqueous batteries. 相似文献
975.
976.
Ming‐Hua Li Shun‐Chang Liu Fa‐Zheng Qiu Zhen‐Yun Zhang Ding‐Jiang Xue Jin‐Song Hu 《Liver Transplantation》2020,10(21)
CsPbI2Br is emerging as a promising all‐inorganic material for perovskite solar cells (PSCs) due to its more stable lattice structure and moisture resistance compared to CsPbI3, although its device performance is still much behind this counterpart. Herein, a preannealing process is developed and systematically investigated to achieve high‐quality CsPbI2Br films by regulating the nucleation and crystallization of perovskite. The preannealing temperature and time are specifically optimized for a dopant‐free poly(3‐hexylthiophene) (P3HT)‐based device to target dopant‐induced drastic performance degradation for spiro‐OMeTAD‐based devices. The resulting P3HT‐based device exhibits comparable power conversion efficiency (PCE) to spiro‐OMeTAD‐based devices but much enhanced ambient stability with over 95% PCE after 1300 h. A diphenylamine derivative is introduced as a buffer layer to improve the energy‐level mismatch between CsPbI2Br and P3HT. A record‐high PCE of 15.50% for dopant‐free P3HT‐based CsPbI2Br PSCs is achieved by alleviating the open‐circuit voltage loss with the buffer layer. These results demonstrate that the preannealing processing together with a suitable buffer layer are applicable strategies for developing dopant‐free P3HT PSCs with high efficiency and stability. 相似文献
977.
Seok Hyun Song Moses Cho Inchul Park Jong‐Gyu Yoo Kyung‐Tae Ko Jihyun Hong Jongsoon Kim Sung‐Kyun Jung Maxim Avdeev Sungdae Ji Seongsu Lee Joona Bang Hyungsub Kim 《Liver Transplantation》2020,10(23)
Layered lithium–nickel–cobalt–manganese oxide (NCM) materials have emerged as promising alternative cathode materials owing to their high energy density and electrochemical stability. Although high reversible capacity has been achieved for Ni‐rich NCM materials when charged beyond 4.2 V versus Li+/Li, full lithium utilization is hindered by the pronounced structural degradation and electrolyte decomposition. Herein, the unexpected realization of sustained working voltage as well as improved electrochemical performance upon electrochemical cycling at a high operating voltage of 4.9 V in the Ni‐rich NCM LiNi0.895Co0.085Mn0.02O2 is presented. The improved electrochemical performance at a high working voltage at 4.9 V is attributed to the removal of the resistive Ni2+O rock‐salt surface layer, which stabilizes the voltage profile and improves retention of the energy density during electrochemical cycling. The manifestation of the layered Ni2+O rock‐salt phase along with the structural evolution related to the metal dissolution are probed using in situ X‐ray diffraction, neutron diffraction, transmission electron microscopy, and X‐ray absorption spectroscopy. The findings help unravel the structural complexities associated with high working voltages and offer insight for the design of advanced battery materials, enabling the realization of fully reversible lithium extraction in Ni‐rich NCM materials. 相似文献
978.
979.
980.
Young Moon Choi Byoung Wan Lee Myung Sun Jung Hyun Soo Han Suk Hyun Kim Kaifeng Chen Dong Ha Kim Tony F. Heinz Shanhui Fan Jihye Lee Gi‐Ra Yi Jung Kyu Kim Jong Hyeok Park 《Liver Transplantation》2020,10(22)
N‐type metal oxides such as hematite (α‐Fe2O3) and bismuth vanadate (BiVO4) are promising candidate materials for efficient photoelectrochemical water splitting; however, their short minority carrier diffusion length and restricted carrier lifetime result in undesired rapid charge recombination. Herein, a 2D arranged globular Au nanosphere (NS) monolayer array with a highly ordered hexagonal hole pattern (hereafter, Au array) is introduced onto the surface of photoanodes comprised of metal oxide films via a facile drying and transfer‐printing process. Through plasmon‐induced resonance energy transfer, the Au array provides a strong electromagnetic field in the near‐surface area of the metal oxide film. The near‐field coupling interaction and amplification of the electromagnetic field suppress the charge recombination with long‐lived photogenerated holes and simultaneously enhance the light harvesting and charge transfer efficiencies. Consequently, an over 3.3‐fold higher photocurrent density at 1.23 V versus reversible hydrogen electrode (RHE) is achieved for the Au array/α‐Fe2O3. Furthermore, the high versatility of this transfer printing of Au arrays is demonstrated by introducing it on the molybdenum‐doped BiVO4 film, resulting in 1.5‐fold higher photocurrent density at 1.23 V versus RHE. The tailored metal film design can provide a potential strategy for the versatile application in various light‐mediated energy conversion and optoelectronic devices. 相似文献