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951.
Hua-Yu Shi Zhongqiu Jia Wanlong Wu Xiang Zhang Prof. Xiao-Xia Liu Prof. Xiaoqi Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(37):8190-8204
Various cathode materials have been proposed for high-performance rechargeable batteries. Vanadyl phosphate is an important member of the polyanion cathode family. VOPO4 has seven known crystal polymorphs with tunneled or layered frameworks, which allow facile cation (de)intercalations. Two-electron transfer per formula unit can be realized by using VV/VIV and VIV/VIII redox couples. The electrochemical performance is closely related to the structures of VOPO4 and the types of inserted cations. This Review outlines the crystal structures of VOPO4 polymorphs and their lithiated phases. The research progress of vanadyl phosphate cathode materials for different energy storage systems, including lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, multivalent batteries, and supercapacitors, as well as the related mechanism investigations are summarized. It is hoped that this Review will help with future directions of using vanadyl phosphate materials for energy storage. 相似文献
952.
Dongyang Qu Dr. Zhonghui Sun Jianan Xu Zhongqian Song Huijun Kong Bolin Zhao Prof. Xiandui Dong Prof. Li Niu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(36):8121-8128
Transition metal oxides have vastly limited practical application as electrode materials for lithium-ion batteries (LIBs) due to their rapid capacity decay. Here, a versatile strategy to mitigate the volume expansion and low conductivity of Fe3O4 by coating a thin carbon layer on the surface of Fe3O4 nanosheets (NSs) was employed. Owing to the 2D core–shell structure, the Fe3O4@C NSs exhibit significantly improved rate performance and cycle capability compared with bare Fe3O4 NSs. After 200 cycles, the discharge capacity at 0.5 A g−1 was 963 mA h g−1 (93 % retained). Moreover, the reaction mechanism of lithium storage was studied in detail by ex situ XRD and HRTEM. When coupled with a commercial LiFePO4 cathode, the resulting full cell retains a capacity of 133 mA h g−1 after 100 cycles at 0.1 A g−1, which demonstrates its superior energy storage performance. This work provides guidance for constructing 2D metal oxide/carbon composites with high performance and low cost for the field of energy storage. 相似文献
953.
Xin-Xin Zhao Zhen-Yi Gu Wen-Hao Li Xu Yang Dr. Jin-Zhi Guo Prof. Xing-Long Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(35):7823-7830
Phosphate cathode materials are practical for use in sodium-ion batteries (SIBs) owing to their high stability and long-term cycle life. In this work, the temperature-dependent properties of the phosphate cathode Na3V2(PO4)2O2F (NVPOF) are studied in a wide temperature range from −25 to 55 °C. Upon cycling at general temperature (above 0 °C), the NVPOF cathode retains an excellent charge/discharge performance, and the rate capability is noteworthy, indicating that NVPOF is a competitive candidate as a temperature-adaptive cathode for SIBs. Upon decreasing the temperature below 0 °C, the cell performance deteriorates, which may be caused by the electrolyte and Na electrode, based on the study of ionic conductivity and electrode kinetics. This work proposes a new breakthrough point for the development of SIBs with high performance over a wide temperature range for advanced power systems. 相似文献
954.
Juyoung Jang Inyeong Kang Jinkwan Choi Dr. Hyangsoo Jeong Prof. Kyung-Woo Yi Dr. Jihyun Hong Dr. Minah Lee 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(34):14581-14588
Prelithiation is of great interest to Li-ion battery manufacturers as a strategy for compensating for the loss of active Li during initial cycling of a battery, which would otherwise degrade its available energy density. Solution-based chemical prelithiation using a reductive chemical promises unparalleled reaction homogeneity and simplicity. However, the chemicals applied so far cannot dope active Li in Si-based high-capacity anodes but merely form solid–electrolyte interphases, leading to only partial mitigation of the cycle irreversibility. Herein, we show that a molecularly engineered Li–arene complex with a sufficiently low redox potential drives active Li accommodation in Si-based anodes to provide an ideal Li content in a full cell. Fine control over the prelithiation degree and spatial uniformity of active Li throughout the electrodes are achieved by managing time and temperature during immersion, promising both fidelity and low cost of the process for large-scale integration. 相似文献
955.
Dr. Yu Ding Xuelin Guo Dr. Yumin Qian Dr. Hongcai Gao Daniel H. Weber Leyuan Zhang Prof. John B. Goodenough Prof. Guihua Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(29):12268-12275
Galvanic replacement reactions have been studied as a versatile route to synthesize nanostructured alloys. However, the galvanic replacement chemistry of alkali metals has rarely been explored. A protective interphase layer will be formed outside templates when the redox potential exceeds the potential windows of nonaqueous solutions, and the complex interfacial chemistry remains elusive. Here, we demonstrate the formation of room-temperature liquid metal alloys of Na and K via galvanic replacement reaction. The fundamentals of the reaction at such low potentials are investigated via a combined experimental and computational method, which uncovers the critical role of solid-electrolyte interphase in regulating the migration of Na ions and thus the alloying reaction kinetics. With in situ formed NaK liquid alloys as an anode, the dendritic growth of alkali metals can be eliminated thanks to the deformable and self-healing features of liquid metals. The proof-of-concept battery delivers reasonable electrochemical performance, confirming the generality of this in situ approach and design principle for next-generation dendrite-free batteries. 相似文献
956.
Highly Concentrated Electrolyte towards Enhanced Energy Density and Cycling Life of Dual-Ion Battery
Li Xiang Dr. Xuewu Ou Xingyong Wang Prof. Zhiming Zhou Xiang Li Prof. Yongbing Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(41):18080-18086
Dual-ion batteries (DIBs) have attracted much attention owing to their low cost, high voltage, and environmental friendliness. As the source of active ions during the charging/discharging process, the electrolyte plays a critical role in the performance of DIBs, including capacity, energy density, and cycling life. However, most used electrolyte systems based on the LiPF6 salt demonstrate unsatisfactory performance in DIBs. We have successfully developed a 7.5 mol kg−1 lithium bis(fluorosulfonyl)imide (LiFSI) in a carbonate electrolyte system. Compared with diluted electrolytes, this highly concentrated electrolyte exhibits several advantages: 1) enhanced intercalation capacity and cycling stability of the graphite cathode, 2) optimized structural stability of the Al anode, and 3) significantly increased battery energy density. A proof-of-concept DIB based on this concentrated electrolyte exhibits a discharge capacity of 94.0 mAh g−1 at 200 mA g−1 and 96.8 % capacity retention after 500 cycles. By counting both the electrode materials and electrolyte, the energy density of this DIB reaches up to ≈180 Wh kg−1, which is among the best performances of DIBs reported to date. 相似文献
957.
Chengyi Wang Dr. Zihe Zhang Weiwei Liu Qinming Zhang Dr. Xin-Gai Wang Dr. Zhaojun Xie Prof. Zhen Zhou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(41):18012-18019
Li-O2 batteries are promising energy storage systems due to their ultra-high theoretical capacity. However, most Li-O2 batteries are based on the reduction/oxidation of Li2O2 and involve highly reactive superoxide and peroxide species that would cause serious degradation of cathodes, especially carbon-based materials. It is important to explore lithium-oxygen reactions and find new Li-O2 chemistry which can restrict or even avoid the negative influence of superoxide/peroxide species. Here, inspired by enzyme-catalyzed oxygen reduction/oxidation reactions, we introduce a copper(I) complex 3 N-CuI (3 N=1,4,7-trimethyl-1,4,7-triazacyclononane) to Li-O2 batteries and successfully modulate the reaction pathway to a moderate one on reversible cleavage/formation of O−O bonds. This work demonstrates that the reaction pathways of Li-O2 batteries could be modulated by introducing an appropriate soluble catalyst, which is another powerful choice to construct better Li-O2 batteries. 相似文献
958.
Unraveling the Beneficial Microstructure Evolution in Pyrite for Boosted Lithium Storage Performance
Jie Wang Jinwen Qin Yan Jiang Baoguang Mao Xin Wang Minhua Cao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(51):11841-11850
Pyrite FeS2 as a high-capacity electrode material for lithium-ion batteries (LIBs) is hindered by its unstable cycling performance owing to the large volume change and irreversible phase segregation from coarsening of Fe. Here, the beneficial microstructure evolution in MoS2-modified FeS2 is unraveled during the cycling process; the microstructure evolution is responsible for its significantly boosted lithium storage performance, making it suitable for use as an anode for LIBs. Specifically, the FeS2/MoS2 displays a long cycle life with a capacity retention of 116 % after 600 cycles at 0.5 A g−1, which is the best among the reported FeS2-based materials so far. A series of electrochemical tests and structural characterizations substantially revealed that the introduced MoS2 in FeS2 experiences an irreversible electrochemical reaction and thus the in situ formed metallic Mo could act as the conductive buffer layer to accelerate the dynamics of Li+ diffusion and electron transport. More importantly, it can guarantee the highly reversible conversion in lithiated FeS2 by preventing Fe coarsening. This work provides a fundamental understanding and an effective strategy towards the microstructure evolution for boosting lithium storage performances for other metal sulfide-based materials. 相似文献
959.
Feifei Lei Yuqing Cao Yifang Fu Yunliang Li Prof. Runwei Wang Prof. Shilun Qiu Prof. Zongtao Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(58):13295-13304
Lithium–sulfur batteries, owing to the multi-electron participation in the redox reaction, possess enormous energy density, which has aroused much attention. Nevertheless, the detrimental shuttle effect, volume expansion, and electrical insulation of sulfur, have hindered their application. To improve the cyclability, a functional host, consisting of Co nanoparticles and N-doped hollow graphitized carbon (Co-NHGC) material, is elaborated, which has the advantages of: 1) the graphitized carbon material working as an electronic matrix to improve the utilization rate of sulfur; 2) the hollow structure relieving the stress change caused by volume expansion; 3) the rich active sites catalyze the electrochemical reaction of sulfur and entrap polysulfides. These advantages significantly improve the performance of the lithium–sulfur batteries. Accordingly, the S@Co-NHGC cathode exhibits excellent initial specific capacity, high coulombic efficiency, and excellent rate performance. This work utilizes a novel method of dopamine in situ etching of a metal–organic framework to synthetize the Co-NHGC host of sulfur, which will hopefully provide inspiration for other energy materials. 相似文献
960.
Scrosati B 《Chemical record (New York, N.Y.)》2005,5(5):286-297
The activities in progress in our laboratory for the development of batteries and fuel cells for portable electronics and hybrid car applications are reviewed and discussed. In the case of lithium batteries, the research has been mainly focused on the characterization of new electrode and electrolyte materials. Results related to disordered carbon anodes and improved, solvent-free, as well as gel-type, polymer electrolytes are particularly stressed. It is shown that the use of proper gel electrolytes, in combination with suitable electrode couples, allows the development of new types of safe, reliable, and low-cost lithium ion batteries which appear to be very promising power sources for hybrid vehicles. Some of the technologies proven to be successful in the lithium battery area are readapted for use in fuel cells. In particular, this approach has been followed for the preparation of low-cost and stable protonic membranes to be proposed as an alternative to the expensive, perfluorosulfonic membranes presently used in polymer electrolyte membrane fuel cells (PEMFCs). 相似文献