Materials for Renewable and Sustainable Energy最新文献

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.

This study reports the performance of simple low-cost synthesized bifunctional Cu/Cu₂O nanoparticles (NPs) used as a catalyst for energy-harvesting applications through of a microfluidic fuel cell (µFC), and further, as cholesterol (Chol) sensor. TEM characterization of the NPs showed spheres between 4 and 10 nm, while XRD and XPS analysis confirmed the composition and preferential crystallographic plane of Cu/Cu₂O. In addition, 25.26 m² g⁻¹ surface area was obtained, which is greater than those commercial materials. NPs showed high activity toward the cholesterol oxidation reaction when were used as a sensor, obtaining a linear interval between 0.5 and 1 mM and 850 µA mM⁻¹ mg⁻¹ of sensitivity and 8.9 µM limit of quantification LOQ. These values are comparable to results previously reported. Moreover, Cu/Cu₂O NPs were used as anode in a µFC with 0.96 V of cell voltage and 6.5 mA cm⁻² and 1.03 mW cm⁻² of current and power density, respectively. This performance is the highest currently reported for cholesterol application as an alternative fuel, and the first one reported for a microfluidic fuel cell system as far as is known. Results showed that the obtained Cu-based NPs presented an excellent performance for the dual application both µFC and sensor, which has potential applications in biomedicine and as an alternative energy source.

Coffee by-products are a renewable, plentiful, cost-effective, and mostly untapped resource that could be used as a biofuel feedstock. However, the energy efficiency and biofuel yields are mostly determined by the biofuel production technologies. Pretreatment procedure, hydrolysis methods, fermentation methods, oil to biodiesel conversion techniques, binders employed, applying pressure and temperature are the main factors to improve the biofuel yields from coffee by-products. This paper examines state-of-the-art methods for increasing biogas, bio-ethanol, biodiesel, briquettes, and pellets outputs from coffee by-products. Pretreatment and co-digestion of coffee by-products with other low carbon to nitrogen ratio animal manure boost the biogas yield of coffee by-products, which is also discussed. A yield of bio-ethanol from coffee by-products was also improved using advanced pretreatment procedures, production processes, and the use of genetically modified yeast strains that ferment the majority of sugar monomers. Additionally, oil extraction methods from spent coffee grounds were reviewed, as well as optimizing biodiesel yield from spent coffe grounds oil. The process of making briquettes and pellets, as well as the types of binders utilized, are discussed. The main novelty of this review is on improving biofuel yields such as biogas, bio-ethanol, biodiesel, briquettes, and pellets from the entire dry cherry coffee beans processing residues, wet coffee (coffee pulp or peeled) beans processing residues, and optimizing oil and biodiesel yield from spent coffee grounds.

The electrical energy storage is important right now, because it is influenced by increasing human energy needs, and the battery is a storage energy that is being developed simultaneously. Furthermore, it is planned to switch the lithium-ion batteries with the sodium-ion batteries and the abundance of the sodium element and its economical price compared to lithium is the main point. The main components anode and cathode have significant effect on the sodium battery performance. This review briefly describes the components of the sodium battery, including the anode, cathode, electrolyte, binder, and separator, and the sources of sodium raw material is the most important in material synthesis or installation. Sea salt or NaCl has potential ability as a raw material for sodium battery cathodes, and the usage of sea salt in the cathode synthesis process reduces production costs, because the salt is very abundant and environmentally friendly as well. When a cathode using a source of Na₂CO₃, which was synthesized independently from NaCl can save about 16.66% after being calculated and anode with sodium metal when synthesized independently with NaCl can save about 98% after being calculated, because sodium metal is classified as expensive matter.

The purpose of this work is to develop a bioanode using the enzymes of glucose oxidase (GOx) and alcohol dehydrogenase (ADH) as catalysts to oxidised glucose and alcohol present in different beverages. The study was carried out using the covalent bonding method for both enzymes via the functionalization of carbon nanofibers for the formation of carboxyl groups that can form bonds with the amine groups of the enzyme, as well as using tetrabutylammonium bromide (TBAB) with Nafion. The optimum operation parameters of both enzymes (pH and temperature) were determined for the later evaluation in a microfluidic fuel cell. In addition, using the scanning electrochemical microscopy technique, a local study of enzymatic processes is used to demonstrate that the enzymes immobilized on the same electrode remain active. The evaluation of the microfluidic fuel cell was carried out using different solutions, 0.01 M glucose, 0.01 M ethanol and a mixture of 0.01 M glucose and 0.01 M ethanol, all in phosphate buffer solutions at pH 7, where it was possible to obtain a maximum performance of 5.07 ± 0.1 mW cm⁻², and there was a significant increase in current density compared to non-composite solutions (glucose or ethanol). In addition, different alcoholic beverages were used to evaluate the versatility and adaptability of the bi-enzymatic anode electrode with the perspective use in Lab-on-a-Chip systems.

Rechargeable batteries have gained a lot of interests due to rising trend of electric vehicles to control greenhouse gases emissions. Among all type of rechargeable batteries, lithium air battery (LAB) provides an optimal solution, owing to its high specific energy of 11,140 Wh/kg comparable to that of gasoline 12,700 Wh/kg. However, LABs are not widely commercialized yet due to the reactivity of the lithium anode with the components of ambient air such as moisture and carbon dioxide. To address this challenge, it is important to understand the effects of moisture on the electrochemical performance of LAB. In this review, the effects of ambient air on the electrochemical performance of LAB have been discussed. The literature on the deterioration in the battery capacity and cyclability due to operation in ambient environment and degradation of lithium anode due to exothermic reaction between lithium and water is reviewed and explained. The effects of using oxygen-selective membrane (OSM) to block moisture and ({mathrm{CO}}_{2}) contamination has also been discussed, along with suitable materials that can act as OSM. It is concluded that the utilization of OSM can not only make the safer operation of LAB in ambient air but could also enhance the electrochemical performance of LAB. Future direction of the research work required to address the associated challenges is also provided.