Sustainable Energy & Fuels最新文献

In recent years, MXenes have achieved remarkable progress in catalysis owing to their distinctive physicochemical properties, such as excellent electrical conductivity, tunable surface functional groups, and unique two-dimensional layered structures. This paper systematically reviews the preparation methods of MXenes (highlighting solution etching with HF as a typical approach and electrochemical etching) and advanced modification strategies (such as heterojunction construction, heteroatom doping, single-atom/diatomic catalyst loading and oxygen vacancy engineering). It focuses on key applications of MXene-derived catalysts in electrocatalysis and photocatalysis, emphasizing catalytic performance metrics such as overpotential, Tafel slope, ammonia/CO yield, and stability. Furthermore, it discusses the common catalytic mechanisms of MXene-based materials from the perspectives of electronic structure regulation and interfacial engineering. Finally, this paper addresses the major challenges currently hindering the practical application of the MXene-based catalysts, such as the environmental toxicity of traditional etching processes, their structural instability in water/oxygen environments, and the trade-offs between the active site density, conductivity, and mass transfer efficiency, while offering a perspective on future progress directions for advancing the development of efficient and sustainable MXene-based catalytic systems.

This article systematically reviews the mechanisms, classifications, and applications of electrolyte additives for lithium-ion batteries. The addition of trace amounts of additives can significantly enhance battery performance, with common types including film-forming agents, flame retardants, acid scavengers, overcharge protectants, and multifunctional composite additives. They play a key role in building a stable SEI/CEI layer at the electrode/electrolyte interface, removing harmful substances (such as HF), regulating the solvation structure of lithium-ions, enhancing thermal stability, and inhibiting dendrite growth. The article discusses in detail the additives containing elements such as boron, phosphorus, sulfur, fluorine, and nitrogen, as well as their synergistic effects. The article also explores emerging directions such as ionic liquids, multifunctional molecules, nanomaterials, polymers, and bio-based additives, and points out the challenges currently faced by additive technologies, including compatibility, mechanism complexity, and long-term effectiveness. It also looks forward to the development prospects of rational design and collaborative strategies for high-voltage, high-energy-density, and solid-state batteries.

Polypyrrole (PPy) serves as an excellent N-rich precursor for Fe-N-C electrocatalysts, as its pyrrolic-N moieties not only facilitate metal coordination but also generate intrinsic carbon defects, promoting the formation of atomically dispersed active sites. However, excessive interchain cross-linking during polymerization often leads to dense, poorly porous carbon structures upon pyrolysis, severely limiting the accessibility of these active sites and overall catalytic performance. Herein, we report a “dynamic coordination motif” strategy by introducing 4-vinylpyridine (vP) as a co-monomer during the Fe-coordinated pyrrole polymerization. vP may compete with pyrrole for Fe coordination, forming dynamic Fe-vP complexes that act as molecular spacers within the growing polymer network. This process effectively inhibited dense chain packing, creates additional coordination anchors for Fe, and guides the formation of a more open architecture. After pyrolysis, this hybrid polymer transforms into a stable porous carbon matrix with rich pyridinic-N and a high density of accessible Fe-N sites. The resultant vP-Fe@PPy catalysts exhibited significantly superior ORR catalytic performance, outperforming both the vP-free, Fe-doped PPy-derived carbon and the commercial Pt/C catalyst. This work presents a facile and effective strategy for engineering highly accessible active sites in metal-doped carbon electrocatalysts, enabling tailorable metal loadings with uniform distribution.

Perovskite solar cells (PSCs) have attracted significant attention due to their rapidly increasing power conversion efficiencies (PCEs), now exceeding 25.8%, along with low-cost fabrication and versatile material tunability. Among the core components of PSCs, hole transport materials (HTMs) play a pivotal role in enhancing charge extraction, suppressing recombination losses, and improving overall device stability. This review highlights the significant progress made from 2020 to 2025 in the development of new π-conjugated organic HTMs for perovskite solar cells (PSCs), with a particular focus on spiro-based structures. Traditional organic HTMs such as spiro-OMeTAD remain widely used, but their reliance on dopants and high cost has prompted the exploration of cost-effective, dopant-free alternatives. Notably, small molecules like TPE-NPD and polymeric HTMs such as PTAA have achieved PCEs exceeding 21%, offering enhanced thermal and chemical stability. Recent advancements in molecular engineering, such as π-conjugation expansion, donor–acceptor design, and the introduction of heteroatoms, have significantly improved hole mobility, film uniformity, and energy level alignment. This review not only summarizes these material developments but also analyzes charge transport mechanisms, interfacial optimization strategies, and stability trade-offs, highlighting promising design concepts for next-generation, efficient, and durable spiro-based HTMs in PSCs.

Supercritical water gasification (SCWG) offers a promising method to process wet biomass and realise its full potential as a renewable energy source, as well as to efficiently treat waste biomass streams. To optimise this technology for more energy-efficient operations, this work provides a comprehensive investigation into the impact of heating rate and profile on the SCWG of biomass. Using an upgraded SCWG kinetic model, process simulations were used to explore the potential in enhancing syngas yields and carbon gasification efficiency, and mitigating char formation by changing sub-critical heating rates and heating profiles (e.g., linear, accelerating, decelerating). Reducing sub-critical heating rates from hundreds to a few °C min⁻¹ is found to be beneficial for increasing the yield of H₂ from the SCWG of cellulose and hemicellulose in particular, where the increase in H₂ yield exceeded 10 °C min⁻¹. The dry mass fraction of char produced from lignin SCWG could be reduced from roughly 30 °C min⁻¹ to 20 °C min⁻¹ by increasing the sub-critical heating rate by two orders of magnitude to 690 °C min⁻¹. The effect of sub-critical heating profile was less significant, with the only notable trend being increased lignin-derived char with a decelerating sub-critical heating profile. This work shows the potential improvements that could be made to SCWG by tailoring the sub-critical heating regime in accordance with the feedstock to optimise syngas yields and char formation.

The aldol condensation of low-molecular-weight biogenic carbonyl compounds plays a pivotal role in constructing longer-chain intermediates for the production of furanic jet fuels. Among these, coupling furfural with ketones has emerged as a promising route due to the high energy density and favorable low-temperature properties of the resulting compounds. In this study, we developed shaped LaCeO_x catalysts to enable an efficient continuous aldol condensation process of furfural and acetone, a key step in the synthesis of furanic jet fuel precursors. Three structured catalyst configurations were evaluated: (i) compressed LaCeO_x powder formed into disk granules, (ii) pelletized LaCeO_x with a bentonite binder, and (iii) a LaCeO_x-coated metal foam monolith. While the disk and pellet catalysts suffered from mechanical degradation and pore blockage due to polymeric byproducts, the metal foam catalyst maintained its structural integrity and exhibited superior productivity. This enhanced performance is attributed to the open-cell structure of the metal foam, which facilitates effective mass transport and suppresses undesired side reactions such as oligomerization. Moreover, the metal foam catalyst demonstrated excellent regenerability via air calcination at 673 K, underscoring its potential for long-term operation. Integration of the optimized aldol condensation with a downstream hydrogenation/hydro-deoxygenation step yielded a furanic jet fuel precursor with an overall carbon yield of approximately 39%, highlighting the feasibility and scalability of this process for renewable aviation fuel applications.

Inverted p–i–n perovskite solar cells (IPSCs) offer promise for next-generation photovoltaics. However, IPSCs utilizing solution-processed PC₆₁BM as the electron transport layer (ETL) remain less interface-optimized than conventional n–i–p configurations, restricting their efficiency, stability, and scalability. In this work, we introduce an ultrathin atomic-layer-deposited SnO_x (ALD-SnO_x) film, fabricated at a low temperature (80 °C), as a versatile interfacial modifier to address these shortcomings. This scalable, vapor-phase approach directly addresses the core instability in p–i–n architectures, effectively remedies morphological defects such as pinholes and phase segregation in PC₆₁BM, significantly enhancing interfacial contact and suppressing charge recombination. Consequently, the champion IPSC incorporating a 10 nm ALD-SnO_x interlayer yields a power conversion efficiency (PCE) of ∼19.2%, representing a remarkable 58% improvement over control devices (PCE ∼11.3%). The ALD-SnO_x interlayer effectively enhances moisture resistance, giving the IPSCs excellent environmental stability. Additionally, the redesigned IPSCs show scalability by effectively generating a large-area (∼12.1 cm²) mini-module with a high PCE (∼14.1%). These findings demonstrate the immense potential of this interfacial engineering approach for the commercial production of scalable, stable, and effective IPSCs.

Manganese dioxide (MnO₂) has demonstrated significant potential in electrochemical energy storage and catalytic applications due to its low cost, environmental friendliness, and polymorphic structures. Electrodeposition is an efficient and controllable technique that enables direct deposition of uniform MnO₂ thin films on conductive substrates; their morphology and performance can be tuned by adjusting parameters such as electrolyte composition and current density. This review systematically summarizes the principles of anodic and cathodic deposition of MnO₂, compares the advantages and limitations of potentiostatic, galvanostatic, pulsed, and cyclic voltammetric electrodeposition methods, and explores its applications in batteries, supercapacitors, metal electrowinning anodes, and electrocatalysis. MnO₂ film electrodes exhibit outstanding performance in enhancing battery capacity and stability, improving supercapacitor-specific capacitance, reducing anode overpotential, and boosting catalytic activity. However, challenges such as low conductivity, insufficient structural stability, and the need for scalable fabrication optimization remain. Further advancements in process engineering are essential to accelerate industrial applications.

In the context of carbon emission reduction, this study investigates the mixed combustion characteristics of zero-carbon hydrogen and ethane—the second major component of natural gas—under gas turbine operating conditions. Ethane not only has fuel properties but also serves as a chemical feedstock (for ethylene production). The quantitative relationship between laminar flame speed and key free radicals (O, H, and OH) was analyzed, and the underlying mechanism of the influence of free radicals on combustion speed was decoupled, considering the effects of heat, mass transfer, and chemical interactions. The study shows that under heated and pressurized conditions in the gas turbine, the hydrogen addition can significantly increase the laminar burning velocity (LBV) of ethane, as hydrogen enhances the concentrations of H, O, and OH free radicals. More importantly, a clear linear positive correlation exists between the LBV and the peak mole fractions of H, O, and OH species. The addition of hydrogen alters the linear correlation coefficient of the above linear relationship, but the linear relationship between LBV and the peak molar fractions of H, O and OH is not affected by pressure and equivalent ratio. The change in the linear correlation coefficient caused by hydrogenation is mainly influenced by chemical effects, followed by thermal effects, with the least impact from transport effects. These numerical results can provide a valuable reference for the design and operational condition selection of gas turbine combustors.

This paper investigates the opportunity to produce chemicals from carbon dioxide rich side streams from the agro-industry by the application of carbon capture and utilisation (CCU) technologies. It takes into consideration economic feasibility and puts the potential from sugar beet factories into perspective by comparison with current plastic use and forest area that would be needed to reach a comparable carbon dioxide uptake. A sugar beet factory with anaerobic digestion of sugar beet pulp and fermentation of molasses to ethanol was reviewed as a potential point source of carbon dioxide. Ethanol and methanol were taken as example chemicals produced via CCU. Ethanol is assumed to be produced via gas fermentation and methanol via reversed water gas shift and subsequent methanol synthesis. Mass balances and economic key figures on relevant technologies were taken from literature. In the default scenario, the production costs are 1738 € per ton for ethanol and 1058 € per ton for methanol. In both cases, the major cost factor is the use of electricity that is largely used for the reduction of carbon dioxide. If a significant penalty for fossil carbon dioxide emission (189 € per ton CO_2eq) is in place, the costs of production of methanol from carbon dioxide are comparable with current methanol prices under the energy surplus scenario (energy costs reduced from 100 € per MWh to 50 € per MWh and doubled capital costs). Ethanol can be converted to ethylene to produce biobased polymers. The use of carbon dioxide from sugar beet processing could fulfil half of the future ethylene biobased plastic demand under the assumption that recycling will reduce the demand for virgin plastics by 50%.