全文获取类型
收费全文 | 1699篇 |
免费 | 398篇 |
国内免费 | 289篇 |
专业分类
化学 | 1015篇 |
晶体学 | 5篇 |
力学 | 162篇 |
综合类 | 8篇 |
数学 | 542篇 |
物理学 | 654篇 |
出版年
2024年 | 10篇 |
2023年 | 51篇 |
2022年 | 99篇 |
2021年 | 103篇 |
2020年 | 147篇 |
2019年 | 117篇 |
2018年 | 98篇 |
2017年 | 85篇 |
2016年 | 108篇 |
2015年 | 105篇 |
2014年 | 135篇 |
2013年 | 144篇 |
2012年 | 120篇 |
2011年 | 108篇 |
2010年 | 69篇 |
2009年 | 80篇 |
2008年 | 88篇 |
2007年 | 70篇 |
2006年 | 90篇 |
2005年 | 53篇 |
2004年 | 66篇 |
2003年 | 35篇 |
2002年 | 54篇 |
2001年 | 56篇 |
2000年 | 29篇 |
1999年 | 33篇 |
1998年 | 39篇 |
1997年 | 32篇 |
1996年 | 29篇 |
1995年 | 19篇 |
1994年 | 12篇 |
1993年 | 14篇 |
1992年 | 15篇 |
1991年 | 6篇 |
1990年 | 11篇 |
1989年 | 12篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1982年 | 7篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1975年 | 2篇 |
排序方式: 共有2386条查询结果,搜索用时 31 毫秒
91.
Photocatalytic Water Oxidation by a Pyrochlore Oxide upon Irradiation with Visible Light: Rhodium Substitution Into Yttrium Titanate
下载免费PDF全文
![点击此处可从《Angewandte Chemie (International ed. in English)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Borbala Kiss Dr. Christophe Didier Timothy Johnson Dr. Troy D. Manning Dr. Matthew S. Dyer Dr. Alexander J. Cowan Dr. John B. Claridge Prof. James R. Darwent Prof. Matthew J. Rosseinsky 《Angewandte Chemie (International ed. in English)》2014,53(52):14480-14484
A stable visible‐light‐driven photocatalyst (λ≥450 nm) for water oxidation is reported. Rhodium substitution into the pyrochlore Y2Ti2O7 is demonstrated by monitoring Vegard′s law evolution of the unit‐cell parameters with changing rhodium content, to a maximum content of 3 % dopant. Substitution renders the solid solutions visible‐light active. The overall rate of oxygen evolution is comparable to WO3 but with superior light‐harvesting and surface‐area‐normalized turnover rates, making Y2Ti1.94Rh0.06O7 an excellent candidate for use in a Z‐scheme water‐splitting system. 相似文献
92.
Nanocomposites of Tantalum‐Based Pyrochlore and Indium Hydroxide Showing High and Stable Photocatalytic Activities for Overall Water Splitting and Carbon Dioxide Reduction
下载免费PDF全文
![点击此处可从《Angewandte Chemie (International ed. in English)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Meng‐Chun Hsieh Guan‐Chang Wu Dr. Wei‐Guang Liu Prof. William A. Goddard III Prof. Dr. Chia‐Min Yang 《Angewandte Chemie (International ed. in English)》2014,53(51):14216-14220
Nanocomposites of tantalum‐based pyrochlore nanoparticles and indium hydroxide were prepared by a hydrothermal process for UV‐driven photocatalytic reactions including overall water splitting, hydrogen production from photoreforming of methanol, and CO2 reduction with water to produce CO. The best catalyst was more than 20 times more active than sodium tantalate in overall water splitting and 3 times more active than Degussa P25 TiO2 in CO2 reduction. Moreover, the catalyst was very stable while generating stoichiometric products of H2 (or CO) and O2 throughout long‐term photocatalytic reactions. After the removal of In(OH)3, the pyrochlore nanoparticles remained highly active for H2 production from pure water and aqueous methanol solution. Both experimental studies and density functional theory calculations suggest that the pyrochlore nanoparticles catalyzed the water reduction to produce H2, whereas In(OH)3 was the major active component for water oxidation to produce O2. 相似文献
93.
Min Wang Jia-Qi Wang Cong Xi Chuan-Qi Cheng Cheng-Qin Zou Rui Zhang Ya-Meng Xie Zhong-Lu Guo Prof. Cheng-Chun Tang Dr. Cun-Ku Dong Prof. Yong-Jun Chen Prof. Xi-Wen Du 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(28):11607-11612
Developing highly efficient and low-cost photocatalysts for overall water splitting has long been a pursuit for converting solar power into clean hydrogen energy. Herein, we demonstrate that a nonstoichiometric nickel–cobalt double hydroxide can achieve overall water splitting by itself upon solar light irradiation, avoiding the consumption of noble-metal co-catalysts. We employed an intensive laser to ablate a NiCo alloy target immersed in alkaline solution, and produced so-called L-NiCo nanosheets with a nonstoichiometric composition and O2−/Co3+ ions exposed on the surface. The nonstoichiometric composition broadens the band gap, while O2− and Co3+ ions boost hydrogen and oxygen evolution, respectively. As such, the photocatalyst achieves a H2 evolution rate of 1.7 μmol h−1 under AM 1.5G sunlight irradiation and an apparent quantum yield (AQE) of 1.38 % at 380 nm. 相似文献
94.
Dr. Linzhou Zhuang Dr. Yi Jia Hongli Liu Zhiheng Li Dr. Mengran Li Dr. Longzhou Zhang Dr. Xin Wang Prof. Dongjiang Yang Prof. Zhonghua Zhu Prof. Xiangdong Yao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(34):14772-14778
The oxygen vacancies of defective iron–cobalt oxide (FeCoOx-Vo) nanosheets are modified by the homogeneously distributed sulfur (S) atoms. S atoms can not only effectively stabilize oxygen vacancies (Vo), but also form the Co−S coordination with Co active site in the Vo, which can modulate the electronic structure of the active site, enabling FeCoOx-Vo-S to exhibit much superior OER activity. FeCoOx-Vo-S exhibits a mass activity of 2440.0 A g−1 at 1.5 V vs. RHE in 1.0 m KOH, 25.4 times higher than that of RuO2. The Tafel slope is as low as 21.0 mV dec−1, indicative of its excellent charge transfer rate. When FeCoOx-Vo-S (anode catalyst) is paired with the defective CoP3/Ni2P (cathode catalyst) for overall water splitting, current densities of as high as 249.0 mA cm−2 and 406.0 mA cm−2 at a cell voltage of 2.0 V and 2.3 V, respectively, can be achieved. 相似文献
95.
Jin Su Takashi Hisatomi Tsutomu Minegishi Kazunari Domen 《Angewandte Chemie (International ed. in English)》2020,59(33):13800-13806
Most CdTe photoanodes and photocathodes show positive and negative photocurrent onset potentials for water oxidation and reduction, respectively, and are thus unable to drive photoelectrochemical (PEC) water splitting without external applied biases. Herein, the activity of a CdTe photoanode having an internal p‐n junction during PEC water oxidation was enhanced by applying a CdCl2 annealing treatment together with surface modifications. The resulting CdTe photoanode generated photocurrents of 1.8 and 5.4 mA cm?2 at 0.6 and 1.2 VRHE, respectively, with a photoanodic current onset potential of 0.22 VRHE under simulated sunlight (AM 1.5G). The CdCl2 annealing increased the grain sizes and lowered the density of grain boundaries, allowing more efficient charge separation. Consequently, a two‐electrode tandem PEC cell comprising a CdTe‐based photoanode and photocathode split water without any external bias at a solar‐to‐hydrogen conversion efficiency of 0.51 % at the beginning of the reaction. 相似文献
96.
Shijia Feng Tuo Wang Bin Liu Congling Hu Lulu Li Zhi‐Jian Zhao Jinlong Gong 《Angewandte Chemie (International ed. in English)》2020,59(5):2044-2048
A facile photoetching approach is described that alleviates the negative effects from bulk defects by confining the oxygen vacancy (Ovac) at the surface of BiVO4 photoanode, by 10‐minute photoetching. This strategy could induce enriched Ovac at the surface of BiVO4, which avoids the formation of excessive bulk defects. A mechanism is proposed to explain the enhanced charge separation at the BiVO4 /electrolyte interface, which is supported by density functional theory (DFT) calculations. The optimized BiVO4 with enriched surface Ovac presents the highest photocurrent among undoped BiVO4 photoanodes. Upon loading FeOOH/NiOOH cocatalysts, photoetched BiVO4 photoanode reaches a considerable water oxidation photocurrent of 3.0 mA cm?2 at 0.6 V vs. reversible hydrogen electrode. An unbiased solar‐to‐hydrogen conversion efficiency of 3.5 % is realized by this BiVO4 photoanode and a Si photocathode under 1 sun illumination. 相似文献
97.
Haojie Zhang Dirk J. Hagen Xiaopeng Li Andreas Graff Frank Heyroth Bodo Fuhrmann Ilya Kostanovskiy Stefan L. Schweizer Francesco Caddeo A. Wouter Maijenburg Stuart Parkin Ralf B. Wehrspohn 《Angewandte Chemie (International ed. in English)》2020,59(39):17172-17176
Transition‐metal phosphides (TMP) prepared by atomic layer deposition (ALD) are reported for the first time. Ultrathin Co‐P films were deposited by using PH3 plasma as the phosphorus source and an extra H2 plasma step to remove excess P in the growing films. The optimized ALD process proceeded by self‐limited layer‐by‐layer growth, and the deposited Co‐P films were highly pure and smooth. The Co‐P films deposited via ALD exhibited better electrochemical and photoelectrochemical hydrogen evolution reaction (HER) activities than similar Co‐P films prepared by the traditional post‐phosphorization method. Moreover, the deposition of ultrathin Co‐P films on periodic trenches was demonstrated, which highlights the broad and promising potential application of this ALD process for a conformal coating of TMP films on complex three‐dimensional (3D) architectures. 相似文献
98.
Rafael M. de Almeida Victoria C. Ferrari Dr. Juliana dos S. Souza Dr. Flavio L. Souza Wendel A. Alves 《Chemphyschem》2020,21(6):476-483
Herein, a detailed investigation of the surface modification of a zinc oxide (ZnO) nanorod electrode with FeOOH nanoparticles dispersed in glycine was conducted to improve the water oxidation reaction assisted by sunlight. The results were systematically analysed in terms of the general parameters (light absorption, charge separation, and surface for catalysis) that govern the photocurrent density response of metal oxide as photoanode in a photoelectrochemical (PEC) cell. ZnO electrodes surface were modified with different concentration of FeOOH nanoparticles using the spin-coating deposition method, and it was found that 6-layer deposition of glycine-FeOOH nanoparticles is the optimum condition. The glycine plays an important role decreasing the agglomeration of FeOOH nanoparticles over the ZnO electrode surface and increasing the overall performance. Comparing bare ZnO electrodes with the ones modified with glycine-FeOOH nanoparticles an enhanced photocurrent density can be observed from 0.27 to 0.57 mA/cm2 at 1.23 VRHE under sunlight irradiation. The impedance spectroscopy data aid us to conclude that the higher photocurrent density is an effect associated with more efficient surface for chemical reaction instead of electronic improvement. Nevertheless, the charge separation efficiency remains low for this system. The present discovery shows that the combination of glycine-FeOOH nanoparticle is suitable and environmentally-friend cocatalyst to enhance the ZnO nanorod electrode activity for the oxygen evolution reaction assisted by sunlight irradiation. 相似文献
99.
100.
Dye-sensitized photoelectrochemical tandem cells have shown the promise for light driven hydrogen production from water owing to the low cost,wide absorption spectra in the visible region and ease to process of their constitutive photoelectrode materials.However,most photo-driven water splitting photoelectrochemical cells driven by organic dye sensitized solar cells exhibit unsatisfactory hydrogen evolution rate,primarily attributed to their poor light capturing ability and low photocurrent performance.Here we present the construction of a tandem system consisting of an organic blue-colored S5 sensitizer-based dyesensitized photoelectrochemical cell(DSPEC) wired in series with three spectral-complemental dyes BTA-2,APP-3 and APP-1 sensitizers-based dye-sensitized solar cell(DSC),respectively.The two spectral-complemental chromophores were used in DSC and DSPEC to ensure that the full solar spectrum could be absorbed as much as possible.The results showed that the photocurrent of tandem device was closely related to the open-circuit voltage(Voc) of sensitized DSC,in which the tandem configuration consisting of S5 based DSPEC and BTA-2 based DSC gave the best photocurrent.On this basis,tandem device with the only light energy and no external applied electrical bias was further constructed of BTA-2 based 2-junction DSC and S5 based DSPEC and obtained a photocurrent of 500 μA cm-2 for hydrogen generation.Furthermore,I-/I3-was used as a redox couple between dye regeneration and O2 production on the surface of Pt-IrO2/WO3.The strategy opens up the application of pure organic dyes in DSC/DSPEC tandem device. 相似文献