Sustainable Energy & Fuels最新文献

Multifarious food wastes can be transformed into renewable, decentralized biofuels through optimized bioprocessing. In this context, converting food waste into bioethanol provides a sustainable solution for both solid waste management and the energy crisis. Bioethanol from pretreated food waste produces minimal CO₂ and CO emissions, making it a climate-positive alternative to fossil fuels. Therefore, this review critically focuses on maximizing bioethanol production from food waste polysaccharides by shedding light on the progress of different pretreatment methods in the anaerobic fermentation (AF) process. First, this review comprehensively addresses the current scenario of food waste accumulation in India and worldwide and its mitigation strategies. Further, it extensively discusses various pretreatment methods for food waste, such as physical, chemical, physiological, and biological processes, to understand contemporary accomplishments. The integration of artificial intelligence techniques, such as artificial neural networks (ANNs), in the food waste-based bioethanol production was discussed. A detailed case study of per-annual food waste accumulation at the Vellore Institute of Technology (VIT), India, is included for bioethanol production under various climatic conditions. Eventually, the valorization of food waste for sustainable bioethanol production and the utilization of genetically engineered microbial cells for bioethanol production and their technical hurdles are articulated.

Novel Lindqvist-type polyoxometalate (POM)-based catalysts Mo₆–NH₂-MIL-125/g-C₃N₄ have been synthesized via a solvent evaporation method and applied in the photo-thermal extraction catalytic oxidative desulfurization system (PTECODS). The structure, composition, and morphology of the catalysts were characterized using various techniques, including X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), N₂ adsorption–desorption, UV-visible spectroscopy, and others. Mo₆ was uniformly dispersed and acted as an electron acceptor, effectively suppressing the recombination of electron–hole pairs under light irradiation. In PTECODS, with 0.03 g Mo₆–NH₂-MIL-125/g-C₃N₄ photocatalysts (Ti : Mo molar ratio of 1 : 0.5), an O/S ratio of 6 : 1, and [Bmim]PF₆ as the extraction agent, the conversion efficiency of DBT approached 100% within 60 min at 70 °C upon exposure to visible light irradiation. The synergistic interactions between Mo₆–NH₂-MIL-125 and g-C₃N₄ and also between photocatalysis and thermocatalysis contributed to the enhanced oxidative desulfurization performance. The catalysts could be recycled at least eight times without a noticeable decrease in catalytic activity. Finally, a thorough discussion of the potential mechanisms underlying the photo-thermal extraction catalytic oxidative desulfurization process is presented.

This paper focuses on the feasibility of utilizing crop residues for biofuel production as a sustainable alternative, incorporating environmental benefits with renewable energy production. Crop stubble and straw management is a serious challenge in the world as well as in Australian agriculture. Retention and burning of crop residues are the main practices in Australia which have negative environmental consequences. This study explores technical, economic, and other challenges related to biofuel production, including feedstock collection, variability in crop residue composition, and infrastructure development. The opportunities to use Australia's abundant agricultural residues for biofuel production are critically reviewed in the context of practices and technologies. Different technological advancements in the transformation of crop residues (CRs) to biofuel are presented and analysed. The challenges and prospects of biofuel production from crop residues are discussed and analysed in this paper. From the literature, it is found that although challenges exist, investment in biofuel technology, infrastructure and supportive policies could change crop stubble from a waste product into a useful resource, fostering sustainable energy and agricultural practices in Australia. The utilisation of crop residues and biomass waste in Australia remains underdeveloped compared to global benchmarks but holds huge potential that can flourish with supportive policies and investment which can make Australia a regional leader in bioenergy. The adaptation of biofuel production from crop residues can alleviate negative sustainability implications of burning fossil fuels and support to achieve net zero 2050.

Biodiesel is widely regarded as a promising renewable energy source with minimal environmental impact. In our study, a novel catalyst, BaO/ZnO (BZO), was synthesized using a wet-impregnation method and used in biodiesel production from waste cooking oil. The synthesized catalysts were physico–chemically characterized using different analytical techniques, including TGA, XRD, FTIR, BET, XPS, HR-SEM, and HR-TEM. NMR analysis was employed to quantify the synthesized biodiesel. The Box–Behnken Design (BBD) model in the Response Surface Methodology (RSM) approach was implemented to optimize various reaction parameters involved in biodiesel production. The maximum biodiesel conversion of 97.3% and yield of 97.1% were obtained under optimized transesterification reaction conditions of 2.6 wt% catalyst loading at 39.9 °C reaction temperature with a MeOH to oil molar ratio of 10.9 : 1 for a reaction time of 29.8 min. In addition, the synthesized BZO catalyst was recyclable up to five times, suggesting higher catalytic efficacy and stability throughout the reaction. The turnover frequency of the proposed catalyst was found to be 15.52 h⁻¹. Kinetic and thermodynamic studies revealed that the obtained values of activation energy (E_a), enthalpy of activation (ΔH^#), and entropy of activation (ΔS^#) were 37.64 kJ mol⁻¹, 35.76 kJ mol⁻¹, and −150.73 J mol⁻¹ K⁻¹, respectively. Moreover, various fuel properties like kinematic viscosity, calorific value, flash point, pour point, and cloud point were consistent with ASTM D-6751 international standards. A green metrics study demonstrates that the overall biodiesel production process is sustainable and environmentally friendly.

Perovskite solar cells (PSCs) have emerged as leading candidates for next-generation photovoltaics owing to their outstanding power conversion efficiencies (PCEs), low-cost materials, and compatibility with low-temperature, solution-based fabrication techniques. While certified PCEs of 27.0% have been reached on rigid substrates, transitioning to scalable, flexible architectures introduces new challenges. This review highlights recent advancements in flexible PSCs (F-PSCs), including the development of low-temperature-processed charge transport materials, flexible transparent electrodes, and encapsulation strategies that maintain mechanical robustness under deformation. Scalable deposition techniques, such as blade coating, slot-die coating, and spray coating, are also discussed, with respect to film uniformity, process control, and compatibility with roll-to-roll (R2R) manufacturing. The integration of solvent and additive engineering, along with interfacial modifications, is shown to be critical in optimizing film morphology and enhancing device performance. Notably, recent studies report flexible perovskite modules achieving PCEs exceeding 17% across active areas larger than 100 cm². Beyond the PCE, this review addresses critical issues in ensuring long-term operational stability, including mechanical reliability and environmental degradation from moisture, oxygen, light, and thermal stress. Strategies such as multi-cation perovskite formulations, advanced interfacial modification, and high-barrier encapsulants are evaluated for their role in enhancing long-term operational stability. Finally, we provide a forward-looking perspective on the technical gaps and collaborative efforts required, across materials science, engineering, and industrial scale-up, to enable the commercial application of F-PSCs.

Reducing the carbon intensity of maritime transport is essential to achieve global emission reduction targets. Electro-fuels (e-fuels) represent a promising cleaner alternative to conventional marine fossil fuels, offering potential lifecycle greenhouse gas reductions when synthesised from renewable electricity and low-carbon feedstocks. While techno-economic and environmental assessments of e-fuels exist, their broader sustainability implications, spanning technological, economic, environmental and safety factors together, remain largely unexplored. This study introduces a quantitative framework to assess the sustainability of ship fuel systems that integrates key performance indicators (KPIs) across these four areas. A case study is conducted to compare the sustainability of carbon-based e-fuels (e-methanol and e-diesel) and carbon-free e-fuels (hydrogen and ammonia) against marine diesel oil (MDO) under multiple decision-making perspectives. The robustness of the overall sustainability-based ranking of fuel alternatives, as derived under each perspective, against uncertainties in the individual KPIs is confirmed via sensitivity analysis. Environmental and safety aspects are found to be critical in comparing the sustainability of alternative fuels. Both e-methanol and e-diesel achieve higher overall sustainability than MDO, irrespective of the decision-making perspective. Ammonia and hydrogen are hindered by safety concerns in the short term, although ammonia also shows long-term potential for sustainable shipping subject to appropriate risk management and the implementation of inherently safer design measures. Overall, the proposed framework enables a comprehensive assessment of alternative fuel systems for cleaner shipping, guiding future sustainability-driven policy and technology development.

Electrochemical CO₂ reduction (CO₂RR) holds promise for carbon-neutral fuel production but is hindered by the competing hydrogen evolution reaction (HER) and slow kinetics. This study investigates how cationic solvation engineering with 18-crown-6 ether (18C6) impacts CO₂RR by selectively coordinating potassium ions (K⁺). 18C6 disrupts the K⁺ hydration shell, shifting the proton source from water to bicarbonate, suppressing HER, and enhancing CO₂RR. Experimental results show a 7.3-fold increase in CO faradaic efficiency (FE) with optimized 18C6 concentrations in 1 M KHCO₃. The non-monotonic relationship between CO production rates and 18C6 concentration highlights the balance between water and bicarbonate protonation processes. In situ ATR-FTIR and Raman analyses reveal reduced water adsorption and enhanced carbonate interactions at the electrode interface. Temperature-dependent electrochemical impedance spectroscopy demonstrates a lowered desolvation energy barrier (83.4 vs. 32.1 kJ mol⁻¹), indicating facilitated dehydration of solvated K⁺. This work provides insights into the mechanistic role of cationic solvation, offering a strategy for improving CO₂RR efficiency.

Identifying effective synthesis strategies that can obtain high-performance electrocatalysts is pivotal to realizing a hydrogen economy. Nickel–cobalt (NiCo) alloy electrocatalysts are promising candidates for the hydrogen evolution reaction (HER), but the traditional approach for synthesizing NiCo alloy electrocatalysts is generally time-consuming, and the physiochemical features of the resulting NiCo are unsatisfactory. Herein, we report the ultrafast synthesis of NiCo alloy nanocatalysts with a Joule heating (JH) approach. We show that ultrasmall NiCo alloy nanoparticles that are uniformly and intimately distributed on carbon cloth can be obtained in just 0.6 seconds using the JH approach, while the NiCo catalysts prepared by traditional thermal treatment exhibit agglomerated and large particles. The as-prepared NiCo alloy electrocatalyst with JH shows favorable activity for the HER with low overpotentials of 83 and 220 mV to achieve current densities of 10 and 100 mA cm⁻², respectively, outperforming the NiCo alloy electrocatalysts prepared using traditional approaches. Moreover, the NiCo alloy electrocatalyst maintains excellent stability during the long-term reaction for 200 h, demonstrating its potential for large-scale deployment.

Exploring renewable and sustainable energy materials as substitutes for fossil fuels presents a promising approach for addressing global challenges such as energy scarcity and environmental degradation. Transition metal dichalcogenide (TMD)-based heterostructured materials have emerged as promising electrocatalysts, garnering increasing interest due to their high efficiency in the hydrogen evolution reaction (HER) and/or oxygen evolution reaction (OER). This review provides an outline of the current advancements in using TMD-based heterostructured materials as electrocatalysts for the HER and OER. We begin with a comprehensive introduction to the fundamentals of electrochemical water splitting, followed by an overview of various TMD-based heterostructure combinations, a summary of the different synthesis techniques, and a discussion of the characterization methods employed for these materials. Moreover, special attention is given to structure–performance relationship strategies aimed at enhancing the electrocatalytic activity and durability of TMD-based heterostructured materials for the HER and OER. Finally, we discuss the existing challenges and provide insights into future prospects for TMD-based heterostructured materials as electrocatalysts in water-splitting technologies.

Metal-supported solid oxide fuel cells (MS-SOFCs) have recently emerged as a promising configuration to reduce material costs and increase the mechanical robustness of solid oxide technologies. Recently, experimental research has focused on addressing fabrication challenges and degradation mechanisms. Computational modelling of MS-SOFCs remains limited, although there are potential benefits to simulation based analysis and optimization. This paper presents the current status of MS-SOFC research, with particular attention to support structures and degradation mechanisms. The paper also presents a foundation for modelling SOFCs at the cell scale, and highlights recent literature that could be adapted for MS-SOFC research. In addition to conventional computational modelling, the potential of data-driven methods such as surrogate models is reviewed for future work. This is the first focused review on computational approaches for MS-SOFCs, providing a foundation for future modelling and optimization of these emerging cell architectures.