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- 实验方案
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A novel growth control of nanoplates WO3 photoanodes with dual oxygen and tungsten vacancies for efficient photoelectrochemical water splitting performance
摘要： Recently, there has been attractive attention over the defect-engineering where the optimum extent of oxygen deficiency has been considered as an effective route towards enhancing the solar-driven water oxidation photocurrent. In this study, a nanoplate-like tungsten oxide with dual oxygen and tungsten vacancies (WO3-x) was successfully fabricated on tungsten foil by acid-mediated hydrothermal treatment to highly improve the photoelectrochemical (PEC) performance of WO3-x photoanode. Thermal annealing at 550 °C in air led to an oxygen deficient surface with a sub-stoichiometric by phase transformation from orthorhombic WO3·.nH2O to γ-monoclinic. However, the optimum number of oxygen vacancies in WO3-x fabricated at 2 h (W-2 h) with compact, porous and uniform nanoplate film that provide a large surface area for efficient charge collecting capability, caused an enhanced photocurrent density of 4.12 mA/cm2 (41.2 mA/W) at 1.6 V vs. Ag/AgCl, as compared to W-3 h (2.59 mA/cm2, or 25.9 mA/W) and W-30 min (1.79 mA/cm2 or 17.9 mA/W). Finally, local variations in dual oxygen and tungsten vacancies and in the electronic band structure of a WO3-x thin film was analyzed with ultraviolet photoelectron spectroscopy (UPS) and UV–visible diffuse reflectance spectroscopy (UV-DRS).
关键词： Photoelectrocatalytic,Water splitting,Growth control,Oxygen and tungsten vacancies,Nanoplates,WO3-X
更新于2025-09-23 15:21:21
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Pure Anatase Phase Titanium Dioxide Films Prepared by Mist Chemical Vapor Deposition
摘要： In this research, pure anatase phase titanium dioxide thin films were successfully fabricated for the first time using the mist chemical vapor deposition method, and optional values for deposition temperature and concentration of titanium tetraisopropoxide were established. It was found that the crystallinity of the titanium dioxide film was significantly improved by increasing the deposition temperature. The best crystallinity of titanium dioxide film was obtained at 400 ?C. It was confirmed that pure anatase phase titanium dioxide films could be obtained using different concentrations of titanium tetraisopropoxide. The lower concentration of titanium tetraisopropoxide produced better crystallinity in the resultant titanium dioxide film. The morphologies of the titanium dioxide thin films were also significantly influenced by the concentration of titanium tetraisopropoxide in the precursor solution.
关键词： titanium dioxide,anatase,thin films,mist chemical vapor deposition,growth control
更新于2025-09-23 15:21:01
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Vacuum‐Assisted Growth of Low‐Bandgap Thin Films (FA <sub/>0.8</sub> MA <sub/>0.2</sub> Sn <sub/>0.5</sub> Pb <sub/>0.5</sub> I <sub/>3</sub> ) for All‐Perovskite Tandem Solar Cells
摘要： All-perovskite multijunction photovoltaics, combining a wide-bandgap (WBG) perovskite top solar cell (EG ≈1.6–1.8 eV) with a low-bandgap (LBG) perovskite bottom solar cell (EG < 1.3 eV), promise power conversion efficiencies (PCEs) >33%. While the research on WBG perovskite solar cells has advanced rapidly over the past decade, LBG perovskite solar cells lack PCE as well as stability. In this work, vacuum-assisted growth control (VAGC) of solution-processed LBG perovskite thin films based on mixed Sn–Pb perovskite compositions is reported. The reported perovskite thin films processed by VAGC exhibit large columnar crystals. Compared to the well-established processing of LBG perovskites via antisolvent deposition, the VAGC approach results in a significantly enhanced charge-carrier lifetime. The improved optoelectronic characteristics enable high-performance LBG perovskite solar cells (1.27 eV) with PCEs up to 18.2% as well as very efficient four-terminal all-perovskite tandem solar cells with PCEs up to 23%. Moreover, VAGC leads to promising reproducibility and potential in the fabrication of larger active-area solar cells up to 1 cm2.
关键词： vacuum-assisted growth control,all-perovskite tandem solar cells,solar cells,large grain,low-bandgap perovskites
更新于2025-09-12 10:27:22
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[Sustainable Energy Developments] Geothermal,Wind and Solar Energy Applications in Agriculture and Aquaculture || Chapter 7: Fundamentals of solar energy
摘要： Modern agricultural systems are characterized by the intensive and optimal use of land and water, turning agricultural exploitation into a semi-industrial concept. Greenhouses are systems suitable both for zones with unfavorable climatic conditions – allowing crop growth regardless of the ambient temperature – and for regions with less restrictive weather – with the aim of increasing crop productivity and improving fruit quality. In this context, a secure and environmentally friendly energy supply must be considered, for any power range or circumstance, including for stand-alone installations. Crop growth is primarily determined by climate and the amount of water and fertilizers applied through irrigation. Therefore, greenhouses are ideal for farming because they allow one to optimize these physical parameters, via the photosynthetic process (Ramírez-Arias et al., 2012), to enhance biomass production. This manipulation requires energy consumption, depending on the crop’s physiological requirements, and the production patterns adopted for yield quantity and timing. The present general concern on the development of more efficient and sustainable productive activities has increased interest in the evaluation of alternatives to the conventional energy sources in the sector; presently many are involved in processes for assessing the environmental feasibility and technological development of such alternatives (Antón et al., 2007; Bojacá et al., 2014; Martínez-Blanco et al., 2011; Page et al., 2012; Romero-Gámez et al., 2012; Torrellas et al., 2013; van der Werf et al., 2014). This work aims to provide an overview of the existing options for the integration of renewable sources in greenhouses located in semi-arid regions where, for example, the high availability of solar radiation facilitates its use for the fulfillment of a certain percentage of the heat and/or electricity loads of greenhouses. Accordingly, this overview contains the basic technological aspects of the main renewable technologies applicable in greenhouses, some simplified design tools and criteria for their selection. Finally, it includes a summary of selected experiences in this field. The main objective is to contribute to a better understanding of the technologies that should support the promotion and development of projects for the implementation of renewable energies in agriculture.
关键词： biomass,geothermal energy,wind energy,semi-arid climates,crop growth control,renewable energy,photovoltaic,greenhouses,energy efficiency,solar energy
更新于2025-09-04 15:30:14