Materials for Renewable and Sustainable Energy最新文献

Tin oxide (SnO₂) films were electrodeposited on graphite substrates using direct and pulse current electrodeposition techniques. The influence of applied current density on the morphological properties, crystal structure, and electrochemical behavior of the resulting films were studied by scanning electron microscope, X-ray diffraction spectroscopy, Mott–Schottky analysis, cyclic voltammetry, and electrochemical impedance spectroscopy techniques. The results showed that pulse electrodeposited films have porous flower-like morphology with smaller crystallite size and high donor density in comparison with direct current electrodeposited films that include equiaxed particles in their morphologies, such characteristics give them better electrochemical performance (higher degree of reversibility, higher specific capacitance, and faster lithium-ion diffusion) than those films that were synthesized by conventional direct current electrodeposition method. Furthermore, using higher applied current densities leads to the improvement of SnO₂ films’ electrochemical performance due to the formation of the films with finer morphology that include more porosity and oxygen vacancies in their respective crystal structure.

We demonstrated the basil sensitized hybrid photoelectrodes for photocurrents and fuel generation. Hybrid photoelectrochemical cells (PECs) were proposed for direct solar energy conversion. The biohybrid device allows tunable control of energy conversion through the chemically stable photoelectrode. Biohybrid PEC was prepared by integrating organic and inorganic layers on fluorine doped tin oxide substrate. This integrated assembly produces electricity upon the illumination of visible light and drives overall water splitting reaction to generate solar fuel. The basil layer enhances the overall absorption with wide spectrum range and hence, a strong increment in generation of photocurrent is observed in the biohybrid PEC device. This hybrid PEC device can also be used to generate solar fuels and solar power.

Activated porous carbon was synthesized from methylcellulose biopolymer through a two-step mechanism involving H₃PO₄ as an activating agent and then thermally carbonized in a tubular furnace under an inert atmosphere at 850 °C. The product was next rinsed with strong HCl, neutralized with deionized water, and dried in an oven at 80 °C. Then, to fully understand the behavior of the activated porous carbon, it was characterized using techniques such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), RAMAN spectroscopy, Brunauer–Emmett–Teller (BET), and thermal gravimetric analysis (TGA). Additionally, we have created dye-sensitive solar cells and an electric double-layer capacitor (EDLC) using this porous carbon produced from methylcellulose (DSSC). We used the above-mentioned prepared porous carbon for the electrode portion of the Electric Double-Layer Capacitor (EDLC) fabrication, and the maximized polymer electrolyte film made from the methyl cellulose (MC) biopolymer combined with 60 wt.% of 1-ethyl-3-methylimidazolium tricyanomethanide ionic liquid (IL), with a maximum conductivity of 1.93 × 10⁻² S/cm, for the electrolyte. The fabricated EDLC device shows a specific capacitance of 60.8 F/gm at 5 mV/s scan rate which was confirmed by cyclovoltammetry and a low-frequency impedance plot in the CH electrochemical workstation. The DSSC device was fabricated using the same porous carbon as a material for the counter-electrode and the same composition polymer electrolyte that had been used in the EDLC as the electrolyte for the DSSC which yields an efficiency of 0.86%. The fill factor and other parameters were also calculated from the JV characteristics that had been characterized and obtained in the solar simulator.

In addition to the fact that most renewable energies such as solar and wind energy have become more competitive in the global energy market, thanks to the great development in conversion technologies, it believes that renewable energy can play a crucial role in global environmental issues. However, in Palestine, the situation is different from anywhere else; renewable energy is not only an economic option, but an absolute necessity to get out of the energy crisis that Palestinian cities suffer from long years ago and continue nowadays. The cornerstone of the present research is focusing on the availability of renewable energy resources in Jenin Governorate (JG)—West Bank (WB)—Palestine. Two-year time-series of hourly solar, wind, biomass, and 1-year hourly electrical load data are used in the analysis in this paper. The energy potentials were estimated using System Advisor Model software (SAM), and the optimum combination and sizing of the hybrid renewable energy system were determined using Hybrid Optimization of Multiple Energy Resources (HOMER). The proposed Hybrid Renewable Energy System (HRES) consists of an 80 MW PV solar field, 66 MW wind farm, and 50 MW biomass system with an initial investment of $323 M. The proposed HRES generates 389 GWh/yr and is enough to meet 100% of the electrical demand of JG (372 GWh/yr) with excess in electricity generation of about 4.57% and the unmeet electric load is about 109.6 MWh/yr which is equivalent to less than 2 h off in a year. The estimated Levelized Cost of Energy (LCOE) was found as 0.313 $/kWh.

Because of the value of hydrogen as the future energy in no distant time, demand for efficient and scalable hydrogen production via electrochemical water splitting process has recently attracted considerable attention from industrial and scientific communities. Yet, several challenges associated with production remain to be addressed. One of the overriding challenges is the sluggish kinetics of oxygen evolution reaction (OER), which can have significant impact on the H₂ production due to overpotential. To overcome this limitation, developing low-cost, robust and stable electrocatalysts very close to the same electrode activity as seen for iridium metal is crucial to solving the efficiency issue in the process. Therefore, timely review of progress in the field is vital to identify the electrocatalytic systems with the highest potential and, more importantly, to understand the factors which have positive contribution towards the electrocatalysts performance. We reviewed the progress made in the direction of designing binary and ternary alloys of transition metal-based electrocatalysts tuned with carbon materials. The review focuses more on the modulation of structural design and electronic conductivity that have been carried out by manipulating chemical compositions to moderate the surface adsorption free energies of the reaction intermediates, targeted to reduce overpotential. The strategic routes are discussed thoroughly with respect to the OER mechanisms and their derived-descriptors. However, numerous opportunities still remain open for exploration, particularly on the key challenge to obtain a route to unify electronic structure-activity and activity-multi-descriptor relationships for rational design of efficient electrocatalysts.

While the first generation of silicon solar cells offers a clean and unlimited energy source, the technology has matured where costs dominate, and the theoretical power conversion efficiency is reaching its limits. The new generation of thin-film solar cells is emerging as an affordable alternative to their bulky counterparts. The technology offers a much cheaper method to quickly fabricate solar cells that use less material with good optical and electronic properties on a wide range of substrates, including flexible materials. In particular, Cu (In_xGa_1−x) (Se)₂ thin-film solar cells are investigated using SCAPS simulation to study the impact of series resistance and doping levels of different layers of the cell structure on the short-circuit current, open-circuit voltage, power conversion efficiency, and fill factor. It was found that an increase in the series resistance of the solar cell layers results in a decrease in the power conversion efficiency with a dependency on light intensities. In addition, the doping level in the absorber and buffer layers plays a significant role in controlling the solar cell’s power conversion efficiency and fill factor values with maximum values when acceptor doping levels are approximately equal to donor doping levels.

Pollution-induced environmental deterioration is one of the serious aspects that must be solved. As a result, biodiesel was made from a novel material (Parsley seed oil) through an alkali-induced transesterification reaction. The efficiency, as well as exhaust emission tests, were performed by running the prepared parsley biodiesel blends (mixture of biodiesel and diesel fuel in different proportions) in an engine. The ideal blend for enhancing engine performance was discovered to be B20, which displayed steady performance attributes without requiring any modifications to the diesel engine. The B20 parsley biodiesel blend had fewer emissions than diesel, notably hydrocarbons, and carbon monoxide except for nitrogen oxides and carbon dioxide. B20 Parsley blends were also shown to emit less pollution than other blends (B5 and B10). A high reduction in CO, CO₂ and HC emissions for B20 was recorded at 33.9%, 29.73%, and 11.38% relative to diesel except for NO_x. Brake-specific energy consumption decreases and thermal efficiency of the engine increases for all biodiesel blends. In addition, from the performance results, BTE and BSFC of B20 are relatively close to those of pure diesel fuel (B0). The use of parsley biodiesel as a diesel engine fuel was shown to be a promising strategy to promote the use of green fuels (biofuels from renewable materials) while simultaneously mitigating the release of toxic greenhouse gases from the combustion of fossil fuel.

Making a consistency with the objectives of circular economy, herein, waste pistachios shells were utilized for the development of hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) electrocatalysts which are the key bottleneck in the technological evolution of electrolyzers and fuel cells, respectively. As an alternative to scarce and expensive platinum-group-metal (PGM) electrocatalysts, metal nitrogen carbons (MNCs) are emerging as a promising candidate for both aforementioned electrocatalysis where iron and nickel are the metal of choice for ORR and HER, respectively. Therefore, FeNCs and NiNCs were fabricated utilizing inedible pistachio shells as a low-cost biosource of carbon. The steps involved in the fabrication of electrocatalyst were correlated with electrochemical performance in alkaline media. Encouraging onset potential of ~ 0.88 V vs RHE with a possibility of a 2 + 2 reaction pathway was observed in pyrolyzed and ball-milled FeNC. However, HF etching for template removal slightly affected the kinetics and eventually resulted in a relatively higher yield of peroxide. In parallel, the pyrolyzed NiNC demonstrated a lower HER overpotential of ~ 0.4 V vs RHE at − 10 mA cm⁻². Nevertheless, acid washing adversely affected the HER performance and consequently, very high overpotential was witnessed.

Recent emphasis on carbon dioxide utilization has necessitated the exploration of different catalyst compositions other than copper-based systems that can significantly improve the activity and selectivity towards specific CO₂ reduction products at low applied potential. In this study, a binary CoTe has been reported as an efficient electrocatalyst for CO₂ reduction in aqueous medium under ambient conditions at neutral pH. CoTe showed high Faradaic efficiency and selectivity of 86.83 and 75%, respectively, for acetic acid at very low potential of − 0.25 V vs RHE. More intriguingly, C1 products like formic acid was formed preferentially at slightly higher applied potential achieving high formation rate of 547.24 μmol cm⁻² h⁻¹ at − 1.1 V vs RHE. CoTe showed better CO2RR activity when compared with Co₃O₄, which can be attributed to the enhanced electrochemical activity of the catalytically active transition metal center as well as improved intermediate adsorption on the catalyst surface. While reduced anion electronegativity and improved lattice covalency in tellurides enhance the electrochemical activity of Co, high d-electron density improves the intermediate CO adsorption on the catalyst site leading to CO₂ reduction at lower applied potential and high selectivity for C₂ products. CoTe also shows stable CO2RR catalytic activity for 50 h and low Tafel slope (50.3 mV dec^–1) indicating faster reaction kinetics and robust functionality. Selective formation of value-added C₂ products with low energy expense can make these catalysts potentially viable for integration with other CO₂ capture technologies thereby, helping to close the carbon loop.