全文获取类型
收费全文 | 512篇 |
免费 | 0篇 |
国内免费 | 8篇 |
专业分类
电工技术 | 1篇 |
综合类 | 1篇 |
化学工业 | 89篇 |
金属工艺 | 9篇 |
建筑科学 | 1篇 |
能源动力 | 354篇 |
无线电 | 10篇 |
一般工业技术 | 51篇 |
原子能技术 | 1篇 |
自动化技术 | 3篇 |
出版年
2024年 | 1篇 |
2023年 | 23篇 |
2022年 | 38篇 |
2021年 | 43篇 |
2020年 | 34篇 |
2019年 | 46篇 |
2018年 | 36篇 |
2017年 | 21篇 |
2016年 | 6篇 |
2015年 | 5篇 |
2014年 | 33篇 |
2013年 | 18篇 |
2012年 | 18篇 |
2011年 | 40篇 |
2010年 | 32篇 |
2009年 | 25篇 |
2008年 | 18篇 |
2007年 | 18篇 |
2006年 | 10篇 |
2005年 | 5篇 |
2004年 | 1篇 |
2003年 | 4篇 |
2002年 | 13篇 |
2001年 | 6篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 4篇 |
1982年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有520条查询结果,搜索用时 15 毫秒
511.
《International Journal of Hydrogen Energy》2019,44(34):18744-18755
Cu2O and CuO provide a unique possibility to tune the band gap into the middle of the efficiency maximum for photoelectrochemical (PEC) and solar cell applications. Photoactive materials containing Cu2O, CuO and Cu2O/CuO have been prepared with high quality and stability in various compositions by an economic, simple and reliable electrodeposition (ED) method. These materials based on copper oxide have been characterized and compared using XRD, SEM, EDX, UV–Vis, PL, FTIR, Raman spectroscopy and electrochemical techniques. Based on the electrochemical production conditions; phase changes of photoactive materials and, at which conditions which phase or phases are present, were evaluated in detail. It was carried out that a full phase change from single-phase Cu2O to single-phase CuO. The crystal dimensions expand as the cube-shaped Cu2O transforms into CuO, crystal surface areas increase, crystal shapes change and turn gradually into flower-shaped crystals. Here, the band gap of copper oxide material can be altered within a broad scale by adjusting the element ratios. The semiconductors have been found to have direct band gap that is more preferred for solar energy applications. PEC performances of the copper oxide electrodes containing a different phase structure were determined, and the changes of PEC activities were examined comparatively. Copper oxide semiconductors have p-type conductivity and they act as photocathodes. 相似文献
512.
《International Journal of Hydrogen Energy》2019,44(37):20826-20838
Quaternary semiconductor film consists of ZnO, ZnSe, CdSe and MoS2 was designed to establish a core-shell structure to achieve the photoelectrochemical oxidation of amoxicillin. The hybrid photoelectrode was fabricated on a FTO substrate from bath deposition methods. The hierarchical ZnSe/CdSe/MoS2 shell was covered uniformly on ZnO nanorod core which provided a direct pathway for electron transfer, large surface area to enhance light absorption and increase active sites. The quaternary photoelectrode exhibited a photocurrent density of 26.86 mA/cm2 at 0 V vs. Ag/AgCl under UV–visible light illumination, which was 31.9 times, 16.7 times and 1.6 times of that of the bare ZnO nanorods, binary ZnO/ZnSe and ternary ZnO/ZnSe/CdSe photoelectrodes, respectively. 10 ppm of amoxicillin was completely degraded in 30 min by the quaternary working electrode with an applied bias of 0.5 V vs. Ag/AgCl. The reusability and stability of quaternary electrode was demonstrated by 3-run recycling experiments. The enhanced photoelectrochemical performance of quaternary photoelectrode can be attributed to the enhancement of light absorption and increased active sites from the coverage of visible-active layers, the accelerated charge separation from the formation of p-n junction and reduced photocorrosion of CdSe from the protection of MoS2 on the surface. 相似文献
513.
Large area nanorod like structured CdS films (9 × 9 cm2) were deposited on the FTO glass substrate using simple and economic spray pyrolysis deposition technique for photoelectrochemical (PEC) hydrogen production. With an intention of electrode scaling-up, the deposition area of photoanode was varied to evaluate its effect on the PEC hydrogen generation capability. High photocurrent of 5 mA has been achieved from the PEC active area of 37.5 cm2. Its unit area (1 cm2) counterpart yielded Solar-to-Hydrogen (STH) conversion efficiency of 0.20% at a bias of 0.2 V vs Ag/AgCl using sacrificial reagents under solar simulator (AM1.5) with 80 mW/cm2 irradiance. The 500 nm thick film exhibiting uniformly distributed nano-rod features yielded 3-times more photocurrent, as well as hydrogen evolution than other films. It exhibited an enhanced photo-activity as indicated by the higher IPCE values (5–9%) in the wavelength range of 450–550 nm. It exhibited superior optical properties (Eg ∼2.4 eV), and formation of high crystallinity hexagonal CdS phase with space group P63MC. The superior performance of the photoanode is attributed to the nanostructured morphology acquired under optimized spray pyrolysis conditions. Large area photoanodes showed unaltered photo-activity indicating the homogeneity in the film properties even in scaled-up version. 相似文献
514.
Shengsen Zhang Biyu Peng Siyuan Yang Yueping Fang Feng Peng 《International Journal of Hydrogen Energy》2013
The influence of the electrodeposition potential on the morphology of Cu2O/TiO2 nanotube arrays (Cu2O/TNA) and their visible-light-driven photocatalytic activity for hydrogen evolution have been investigated for the first time in this work. The photocatalytic hydrogen evolution rate of the as-prepared Cu2O/TNA at the deposition potential of −0.8 V was about 42.4 times that of the pure TNA under visible light irradiation. This work demonstrated a feasible and simple electrodeposition method to fabricate an effective and recyclable visible-light-driven photocatalyst for hydrogen evolution. 相似文献
515.
Dye sensitised photoelectrochemical (PEC) cells based on Cu/p-CuSCN/LB films have been studied with mixed Langmuir Blodgett (LB) films as the dye layer. The effects of mixed layers were investigated in detail by observing the changes of optical absorption and photocurrent in a PEC cell configuration. Enhancements in both optical absorption and photocurrent were found when a mixture of octadecyl methylviolet–C18 (M–C18) and dioctadecyl rhodamine (C18–R–C18) were deposited using the LB technique on p-CuSCN wide band gap semiconductor. The maximum photocurrent quantum efficiency of the PEC cell reached ≈36% in KI (10−2 M)+I2 (10−4 M) electrolyte solution when mixed LB films were used as the dye layer. Photocurrent enhancement is believed to be the enhancement of light absorption of the dye layers due to the interlocking of M–C18 between the double C18 chains of rhodamine. 相似文献
516.
V. M. Pathak K. D. Patel R. J. Pathak R. Srivastava 《Solar Energy Materials & Solar Cells》2002,73(2)
MoSe2, a group VI TMDC, has been found to be highly stable against photocorrosion due to d→d transitions and has a band gap of 1.4 eV.Thus, it possesses high potential towards photoelectronic applications. As grown, MoSe2 based photoelectrochemical (PEC) solar cells are generally found to show low conversion efficiency. It has been shown here that cleaving and controlled chemical and thermal processing can lead to viable levels of photoconversion with high stability. The observed improvement in the behaviour of such solar cells has been attributed to improvements in various parameters like series resistance, minority carriers, diffusion lengths etc. 相似文献
517.
《International Journal of Hydrogen Energy》2020,45(1):123-134
Herein, for the first time, an efficient photoanode engineered with the cascade structure of FTO|c-TiO2|few graphene layers|TiO2/GQDs|Ni(OH)2 assembly (Ni(OH)2 photoanode) is designed. This photoanode exhibited much lower electron–hole recombination, fast charge transport, higher visible light harvesting, and excellent performance with respect to FTO|c-TiO2|TiO2 assembly (TiO2 photoanode) in the photoelectrocatalytic oxygen evolution process. The photocurrent density of Ni(OH)2 photoanode is 7 times (0.35 mA cm−2 at 1.23 V vs. RHE) greater than that of TiO2 photoanode (0.045 mA cm−2 at 1.23 V vs. RHE). The compact TiO2 (c-TiO2) layer in Ni(OH)2 photoanode plays a role of an effective hole-blocking layer. Few-layer graphene layer could speed up the transport of the photogenerated electrons from the conduction band of the TiO2/GQDs to FTO. Ni(OH)2 layer could transfer rapidly holes into electrolyte solution. 相似文献
518.
Photovoltaic and photoelectrochemical systems were prepared by the formation of a thin porous film on silicon. The porous silicon layer was formed on the top of a clean oxide free silicon wafer surface by anodic etching in HF/H2O/C2H5OH mixture (2:1:1). The silicon was then covered by an oxide film (tin oxide, ITO or titanium oxide). The oxide films were prepared by the spray/pyrolysis technique which enables doping of the oxide film by different atoms like In, Ru or Sb during the spray process. Doping of SnO2 or TiO2 films with Ru atoms improves the surface characteristics of the oxide film which improves the solar conversion efficiency.The prepared solar cells are stable against environmental attack due to the presence of the stable oxide film. It gives relatively high short circuit currents (Isc), due to the presence of the porous silicon layer, which leads to the recorded high conversion efficiency. Although the open-circuit potential (Voc) and fill factor (FF) were not affected by the thickness of the porous silicon film, the short circuit current was found to be sensitive to this thickness. An optimum thickness of the porous film and also the oxide layer is required to optimize the solar cell efficiency. The results represent a promising system for the application of porous silicon layers in solar energy converters. The use of porous silicon instead of silicon single crystals in solar cell fabrication and the optimization of the solar conversion efficiency will lead to the reduction of the cost as an important factor and also the increase of the solar cell efficiency making use of the large area of the porous structures. 相似文献
519.
Hematite (α-Fe2O3) is renowned as a promising photoanode for water oxidation, even though it displays poor photoconversion efficiency. In this study, ∼5 nm-thick graphitic carbon nitride (g-C3N4; CN) and metal-incorporated CN (M-CN; M = Ag, Fe, Co) films are uniformly deposited on hematite via a facile one-step evaporation method. Herein, the Co-CN layer leads to the highest photoelectrochemical activity with hematite-based photoanode. The subsequent loading of Co-CN layer with oxygen evolution catalysts (FeNiOOH and CoOOH) further enhances photocurrent density to ∼3.5 mA cm−2 and oxygen evolution at > 95 % of Faradaic efficiency over 24 h at E = 1.23 V. Detailed analysis based on spectroscopic and electrochemical measurements demonstrate that the primary role of CN layer is improving the charge separation efficiency by passivating the hematite surface. Then the incorporated metals contribute to reducing charge transfer resistance and thereby mediating hole transfer to interfacial water. 相似文献
520.
《International Journal of Hydrogen Energy》2023,48(20):7361-7373
To overcome the global challenges of energy crises and environmental threats, urea oxidation is a hopeful route to utilize urea-rich wastewater as an energy source for hydrogen production. Herein, we report an inorganic/organic type of nano-heterostructure (NHs–Ni-TiO2/p-NDIHBT) as a photoanode with excellent urea oxidation efficiency driven by visible light. This heterostructured photoanode consists of nickel (Ni)-doped TiO2 nanorods (NRs) arrays as an inorganic part and a D-A-D type organic polymer i.e p-NDIHBT as an organic part. The as-prepared photoanode was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The morphological studies of TEM confirm the coating of p-NDIHBT on Ni–TiO2 NPs (~1 μm). The consequence of heterostructure formation on optical and photoelectrochemical (PEC) properties of photoanode were explored through photoelectrochemical responses under visible light irradiation. The photoelectrochemical activity of Ni–TiO2 and Ni–TiO2/p-NDIHBT photoanode from linear sweep voltammetry (LSV) shows the ultrahigh photocurrent density of 0.36 mA/cm2 and 2.21 mA/cm2, respectively measured at 1.965 VRHE. Electrochemical impedance spectroscopy (EIS) of both photoanodes shows a highly sensitive nature toward the urea oxidation reaction. The hybrid photoanode also exhibits high photostability, good solar-to-hydrogen conversion efficiency, and high faradaic efficiency for urea oxidation. 相似文献