- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Edge/Defect-rich, Metallic, and Oxygen-heteroatom-doped WS2 Superstructure with Superior Electrocatalytic Performance for Green Solar Energy Conversion
摘要： Two-dimensional tungsten sulfide is widely applied in electrocatalysis field. However, WS2 possesses catalytic active sites located at the layer edge and an inert surface for catalysis. Therefore, increasing the exposure of active sites at the edge and effectively activating the inert sites on the surface is important challenges. Here, we synthesize edge/defect-rich and oxygen-heteroatom-doped WS2 (ED-O-WS2) superstructure. The power-conversion efficiency (PCE) of dye-sensitized solar cells (DSCs) based on ED-O-WS2 counter electrode reach 10.36% (under 1 Sun, AM 1.5, 100 mW cm?2) and 11.19% (under 40 mW cm?2). These values are, to our knowledge, the highest reported efficiency for DSCs based on Pt-free counter electrodes in I3-/I- electrolytes. Analysis of micro-nano structure and electrocatalytic mechanism indicate that ED-O-WS2 exhibit metallic properties in the electrolyte, and that rich edge/defect and oxygen doping in ED-O-WS2 play an important role in improving the catalytic activity of WS2. Moreover, ED-O-WS2 displays better catalytic reversibility for I3-/I- electrolytes than that of noble metal Pt.
关键词： WS2,green solar energy conversion,dye-sensitized solar cells,counter electrode
更新于2025-09-23 15:23:52
-
Assessment of solar energy potential in Gaza Strip-Palestine
摘要： Renewable energy sources and technologies have the potential to provide solutions to the energy problems. Solar energy can be an important part of the Palestinian’s strategies not only to add a new capacity but also to increase energy security, addressing the environmental concerns. In this paper, e?orts have been made to summarize the current status, availability, and future potential of solar energy options in Gaza Strip. Solar radiation data was provided by Meteoblue AG – Switzerland [www.meteoblue.com] as hourly time-series for 15 years from 2000 to 2015 for ?ve cities in Gaza Strip, which are geographically presenting the entire Gaza Strip. Jabalia, Gaza, Deir-Albalah, Khan-Yunis, and Rafah. These data are used directly to evaluate the potential of solar energy in the three selected sites by means of the System Advisor Model (SAM) from National Renewable Energy Laboratory (NREL) software. The potential of solar energy in Palestine using Photovoltaic (PV) and concentrating (CS) solar systems have been discussed. The present study can be considered as a road-map to get out of the electricity crisis in the Gaza Strip and to end the su?ering of Gazians. In this work, two scenarios are suggested, the ?rst one is urgent, it stipulates to generate the demand load (552 GWh/year) by means of (PV) solar power systems. While the second scenario is leading to terminate the reliance on imported energy by producing all the energy needs locally via (PV) solar system. The study reached to determine the ?nancial budget, the levelized cost of electricity (LCOE), and the technical parameters for both scenarios. The urgent action is building up a 555 MWp of (PV) solar system on the rooftop of Gaza Strip’s buildings. This will cost about 800 million $US and the expected price of electricity will be ranged between ($US 0.07–0.11) per kWh, which is four times less than the present price ($US 0.29–0.46) per kWh. The solar energy can lay a strong foundation for an independent the Palestinian state, generate employment opportunities, alleviate poverty and provide a visionary approach to the dreams of Palestinian youths.
关键词： Palestine,Solar energy,Electricity crisis,(PV) solar system,Gaza Strip
更新于2025-09-23 15:23:52
-
[IEEE 2018 2nd International Symposium on Multidisciplinary Studies and Innovative Technologies (ISMSIT) - Ankara, Turkey (2018.10.19-2018.10.21)] 2018 2nd International Symposium on Multidisciplinary Studies and Innovative Technologies (ISMSIT) - The setup cost payback times of 1 kW fixed and dual axis tracking solar energy systems
摘要： In this paper an 80 W optimally tilted fixed solar energy system and an 80 W azimuth-altitude dual solar axis tracking system are designed and analyzed. The systems are mounted on the roof an industrial building in Sakarya, Turkey. The fixed solar energy system is tilted at the yearly optimum tilt angle for the city. The tracking system is designed to follow the Sun’s position by means of solar mathematics. The electrical behavior of the systems are observed for six months and the obtained results are used to evaluate the setup cost payback times of 1 kW applications. In conclusion it is determined that the fixed solar energy system pay back its setup cost in 7.18 years and the tracking solar energy system in 10.73 years.
关键词： solar tracking system,fixed solar energy system,optimally tilted,setup cost payback time
更新于2025-09-23 15:23:52
-
Surface-Immobilized Conjugated Polymers Incorporating Rhenium Bipyridine Motifs for Electrocatalytic and Photocatalytic CO <sub/>2</sub> Reduction
摘要： The solar-driven conversion of CO2 to value-added products provides a promising route for solar energy storage and atmospheric CO2 remediation. In this report, a variety of supporting electrode materials were successfully modified with a [2,2′-bipyridine]-5,5′-bis(diazonium) rhenium complex through a surface-localized electropolymerization method. Physical characterization of the resulting multilayer films confirms that the coordination environments of the rhenium bipyridine tricarbonyl sites are preserved upon immobilization and that the polymerized catalyst moieties exhibit long-range structural order with uniform film growth. UV?vis studies reveal additional absorption bands in the visible region for the polymeric films that are not present in the analogous rhenium bipyridine complexes. Electrochemical studies with modified graphite rod electrodes show that the electrocatalytic activity of these films increases with catalyst loading up to an optimal value, beyond which electron and mass transport through the material become rate-limiting. Electrocatalytic studies performed at ?2.25 V vs Fc/Fc+ for 2 h reveal CO production with faradaic efficiencies and turnover numbers up to 99% and 3606, respectively. Photocatalytic studies of the modified TiO2 devices demonstrate enhanced activity at low catalyst loadings, with turnover numbers up to 70 during 5 h of irradiation.
关键词： metallopolymers,surface modification,photocatalysis,rhenium bipyridine,solar energy conversion,electrocatalysis
更新于2025-09-23 15:23:52
-
A review on photoelectrochemical hydrogen production systems: Challenges and future directions
摘要： Water photolysis is a fundamental concept in which solar-driven water splitting is utilized to generate renewable hydrogen fuel using semiconductor-based electrochemical systems. The engineering design principles for each system configuration, including single, dual/tandem photoelectrodes, tandem photoelectrochemical-photovoltaic, and multi-junction designs are reviewed. Modeling and numerical simulation of photoelectrochemical processes based on up-to-date multi-scale analysis are presented and discussed. In addition, the achievements made in semiconductor photoelectrode materials and the rational engineering methods needed to improve the solar to hydrogen efficiency are demonstrated. Furthermore, some key accomplishments in different aspects, such as electron-hole recombination, stability, photocorrosion, energy band gap, and photocurrent density are discussed. Moreover, key points on the challenges, opportunities and future directions towards commercialization of viable photoelectrochemical reactors are discussed.
关键词： Semiconductor materials,Photoelectrochemical process,Hydrogen production,Solar energy
更新于2025-09-23 15:23:52
-
Efficient degradation of phenol using Sn4+ doped FeOCl as photo-Fenton catalyst
摘要： Sn4+ doped FeOCl has been successfully synthetized as a sunlight-driven photo-Fenton catalyst, which shows that the catalytic activity of Sn4+/FeOCl (1.08% Sn4+ in the Sn4+/FeOCl) is a factor of 11.8 time higher than that of FeOCl. The doping of Sn4+ in FeOCl increases the optical adsorption and surface area of FeOCl. The decreased chemical bond strength of Fe-Cl in Sn4+/FeOCl effectively increases the number of exposed active sites (Fe-site and Sn-site), which boosts the production of ·OH radicals. The Sn-site shows higher catalytic activity than Fe-site. A synergistic mechanism for Sn4+/FeOCl is proposed for the enhanced catalytic performance.
关键词： Solar energy materials,FeOCl,Phenol,Nanocomposites,Fenton reaction,Sn4+
更新于2025-09-23 15:23:52
-
Electron transfer from photoexcited naphthalene-1,4:5,8-bis(dicarboximide) radical anion to Mn(bpy)(CO)3X and Re(bpy)(CO)3X CO2 reduction catalysts linked via a saturated methylene bridge
摘要： Supramolecular systems that connect a naphthalene-1,4:5,8-bis(dicarboximide) (NDI) radical anion donor to Mn(bpy)(CO)3Br or Re(bpy)(CO)3Cl CO2 reduction catalysts via a methylene bridge have been synthesized and studied by femtosecond transient visible, near-infrared and mid-infrared spectroscopy. The use of the methylene bridge to link NDI to the complexes does not affect the reduction potentials of the metal complexes. Selective photoexcitation of NDI?? to 2*NDI?? results in ultrafast reduction of the bipyridine (bpy) ligands on both the Mn and Re complexes to form Mn(I)(bpy??)(CO)3X and Re(I)(bpy??)(CO)3X in near unity quantum yield, respectively. The initial formation of Mn(I)(bpy??)(CO)3X is unexpected based on previous electrochemical data that indicates the Mn(I) center is reduced at a more positive potential than the bpy ligand. Moreover, the rate of forward electron transfer in the Mn complex was found to be faster than in the Re complex, while the rate of the back electron transfer in the Re complex was faster than in the Mn complex.
关键词： Electrochemistry,CO2 reduction,Electron transfer,Radical anions,Femtosecond spectroscopy,Solar energy
更新于2025-09-23 15:23:52
-
Why environmental dust influences solar energy harvesting
摘要： In order to minimize dust effects on optical surfaces related to the solar energy harvesting, adhesion between the active surface of energy harvesting device and the dust particles needs to be lowered. Consequently, the pinning force for the dust particles reduces, and the dust particles can be removed via creating the self‐cleaning effect. The wetting state of the active surface becomes critical towards reducing the pinning force. In this case, hydrophobic surfaces remain favorable reducing the dust adhesion on the surfaces. In the present perspective, characteristics of the environmental dust particles and their effects in humid air ambient are presented. The methods for dust removal from the surfaces and the optical transmittance reduction by the dust particles are discussed. The challenges and future perspectives of surface texturing towards achieving hydrophobicity and optical transmittance are also introduced.
关键词： environmental dust,solar energy harvesting,optical transmittance
更新于2025-09-23 15:23:52
-
Photoelectrochemical hydrogen production from water splitting using heterostructured nanowire arrays of Bi2O3/BiAl oxides as a photocathode
摘要： To date, most metal oxide-based photocathodes used in photoelectrochemical cells for water splitting contain copper cations in its composition, which can be reduced to metal Cu under cathodic bias leading to deactivation of the photoelectrode. Here, a Cu-free photocathode composed by a ternary heterostructure of Bi2O3/Al2Bi24O39/Al2Bi48O75 nanowires is reported with a narrow band gap energy (1.83 eV) and suitable conduction band edge potential (?0.98 VRHE) for water reduction to hydrogen. Photoelectrochemical measurements display that the highest photocurrent density of ?4.85 mA cm?2 at 0 VRHE under simulated sunlight is achieved by tuning the Bi:Al molar ratio of photocathode to 21:1. The photocurrent onset potential of the Bi2O3/BiAl oxides photoelectrode was estimated to be 0.57 VRHE at pH 7, which is comparable to that of silicon. Controlled potential photoelectrolysis at 0 VRHE showed a stable photocurrent of about ?2 mA cm?2 for 2 h of continuous operation. The H2 measured at this time was 696 μmol cm?2, which corresponds to a Faradaic efficiency of 93%. Finally, this work gives a new generation of Cu-free photocathodes and demonstrates a promising future of BiAl oxides in constructing photoelectrochemical devices for water splitting.
关键词： Oxides,Solar energy,PEC cells,Water reduction,Spray pyrolysis,Heterojunction
更新于2025-09-23 15:23:52
-
Practical performance of a small PTC solar heating system in winter
摘要： The active solar house-heating in winter is a novel technology that is eco-friendly and economical. The performance of a small solar heating system composed of parabolic trough collector (PTC) and ventilation pipelines has been experimentally investigated in the current study. With an automatic solar-tracking device, the system adopted a PTC device of aperture area 2.407 m2. The air stream was heated in the tube collector and then driven into the test room. By examining the heat gain of the air stream passing through the PTC as well as the temperature distribution of the indoor air, the working characteristic of the solar-heating system in winter was evaluated practically. The experimental results showed that for the generally-insulated room that was located in 39.87°N latitude, the daily solar heating time reached to 6–7 h, and the thermal efficiency of the PTC device was above 60%. Supposing the heat loss is reduced effectively along the outdoor pipelines in the future, such active solar heating system will be a promising heating technology in regions that are not far north on the earth.
关键词： Thermal efficiency,Solar energy,PTC,House heating
更新于2025-09-23 15:23:52