Sustainable Energy & Fuels最新文献

The electrocatalytic nitrate reduction reaction (NO₃RR) is regarded as a promising strategy to rebalance the global nitrogen cycle. However, the multi-step electron and proton transfer involved in NO₃RR severely compromises its faradaic efficiency; thus, efficient electrocatalysts for NO₃RR are desired to accelerate this process. Herein, we applied the “laser direct-writing” method to fabricate a nanoporous boron-doped DLC electrode for efficient electrocatalytic NO₃RR, and we optimized catalytic activity by modulating the boron doping concentration in the DLC catalyst. It is noted that the electrode achieved a high faradaic efficiency of 80% and an ammonia yield rate of 550 µg cm⁻² h⁻¹ at −0.59 V vs. RHE. In situ Raman spectroscopy combined with X-ray photoelectron spectroscopy (XPS) and multiple characterization techniques indicated that B_0.57DG effectively promoted the reduction of intermediate species. Strong reducing *H species can accelerate hydrogenation during nitrate electroreduction, thereby enhancing the efficiency of ammonia synthesis.

The aviation industry's decarbonization requires sustainable aviation fuel (SAF) feedstocks that do not compete with food resources. In this context, black soldier fly larvae (BSFL) lipids represent a non-food, second-generation feedstock with strong potential for drop-in SAF production. This work presents an integrated evaluation of BSFL-derived lipids hydroprocessed over a commercial Ce/La-doped NiMo/Al₂O₃ catalyst across batch, continuous, and co-processing modes. In batch hydrodeoxygenation (HDO), oxygen was consistently reduced to below the analytical limit of detection, with oil yields averaging 66.3 wt% and reaching a maximum of 72.2 wt%. Maximum kerosene- and diesel-range yields were 37.8 wt% and 29.0 wt%, respectively. Pressure was the dominant factor affecting yields, with temperature–pressure interactions being most significant, while stirring improved performance under mass-transfer-limited conditions. Continuous fixed-bed HDO runs showed that efficient catalyst wetting was achieved at LHSV 0.5 h⁻¹ and H₂/oil ≥800 mL mL⁻¹, conditions under which selectivity shifted toward HDO rather than decarboxylation/decarbonylation (deCO_x). Co-processing BSFL lipids with vacuum gas oil enhanced hydrogen availability, promoted HDO over deCO_x pathways, and yielded high kerosene- and diesel-range fractions, demonstrating the potential for integration of insect-derived lipids into existing refinery infrastructure.

Hydrogen energy is a pillar of the future green energy system and is critical to achieve carbon neutrality, energy security, and sustainable development. Magnesium-based hydrogen storage materials, with environmental air stability and self-evolution characteristics, could optimize dehydrogenation performance with longer air exposure, which is considered to be one of the critical challenges for their large-scale utilization. In this work, the effect of mechanical wet ball milling treatment on the air stability of magnesium-rich nickel hydrides (Mg₈₀Ni₂₀H_x) was investigated by modulating the wet ball milling time. The sample after wet ball milling for 30 min (Mg₈₀Ni₂₀H_x-WM-30 min) exhibited excellent self-evolution specificities and environmental air stability. After air exposure for 14 days, a significant decrease in dehydrogenation temperature of 115 °C occurred, while the air exposed sample could retain 87.32% of the hydrogen storage capacity. It is worth noting that wet ball milling can dramatically reduce the time required for self-evolution while improving the air stability. The smooth surface of the particles produced by wet ball milling can prevent the interior of the particles from reacting with water and oxygen in the air. This work may guide the design and development of reversible metal hydrides with self-evolving effects and air stability.

Carbon capture and utilization (CCU) to produce fuels and chemicals is a promising strategy to reduce greenhouse gas (GHG) emissions. However, net GHG emissions depend heavily on required electricity, hydrogen, and heat, collectively known as background system inputs. We model the cradle-to-gate GHG emissions for 13 chemicals and fuels produced through 20 CCU pathways (8 at or beyond demonstration scale [e.g., methanol from hydrogenation], 5 under lab-scale development [e.g., formic acid from electrochemical reduction], and 7 at research phase [e.g., methane from photocatalytic reaction]), using 12 background system scenarios for Canada from 2020–2050. The CCU chemicals and fuels are compared against the dominant incumbent pathways with the same harmonized background system. Results show that GHG emissions intensities for most of the CCU pathways vary substantially with the background system, with the GHG intensity of electricity being the most impactful factor followed by variation in provision of hydrogen and heat. While low GHG intensity electricity is crucial, it does not guarantee the CCU pathways will have lower GHG intensity than incumbents. Most incumbent pathways are also sensitive to background system changes, thus using fixed values to represent the emissions intensities of incumbent pathways is insufficient. Out of the 20 CCU pathways, 5 have the potential for lower emissions intensity than incumbents in all 2020 scenarios, but only one is currently technically mature and could be deployed at demonstration scale.

Nanoceramics, which have nanoscale structural units and remarkable mechanical, thermal, and electrical properties, are providing transformative benefits for energy systems of the future. This review provides an overview of how nanoceramics are paving the way towards next generation energy systems with high-efficiency energy storage, conversion, and transmission technologies, from lithium-ion batteries to supercapacitors to solid oxide fuel cells (SOFCs) to dielectric capacitors. The nanoceramics' high surface area, tunable dielectric constants, and superior thermal stability provide opportunities for increases in energy density, electrochemical performance, and durability under operating conditions. Notable applications of nanoceramics are discussed related to oxide-based nanoceramics to improve ionic conductivity in SOFCs, high-entropy ceramics for cost-effective capacitors with ultrahigh specific energy storage capabilities, and hybrid nanoceramic–polymer composites for flexible energy device systems. Challenges remain with respect to scalability in processing, composition related grain boundary effects, and lifecycle emissions. New processing technologies, multiscale modelling, and machine learning-enabled design principles offer potential solutions to these challenges in energy storage. The incorporation of nanoceramics into energy systems represents an opportunity to address global sustainability and efficiency concerns through thermoelectric conversion of environmental heat. The potential of nanoceramics as next generation energy technology foundational materials may contribute to developing large scale renewable energy technologies of the future.

Solid Oxide Electrolysis Cells (SOECs) enable high-temperature CO₂ electrolysis, offering enhanced efficiency, faster reaction kinetics, and the potential for direct syngas production—advantages that low-temperature methods often lack due to higher overpotentials and sluggish reaction rates. Among the candidate materials, Sr₂Fe_1.5Mo_0.5O_6−δ (SFM) has gained considerable interest due to its mixed ionic–electronic conductivity, excellent redox stability, and favorable catalytic properties toward CO₂ reduction. However, despite its potential, the practical utilization of SFM is hindered by limitations such as insufficient intrinsic catalytic activity, surface segregation, limited active site density, and performance degradation during long-term operation. In this review, we systematically discuss the origin, structure, and elemental properties of SFM, followed by a comprehensive overview of recent synthesis strategies, including the solid-state reaction method and sol–gel method. Subsequently, various modulation strategies, such as elemental doping, compositing, nano-catalyst infiltration, in situ exsolution, and nanostructure engineering are discussed to demonstrate pathways for enhancing catalytic activity, stability, and overall performance. To address degradation concerns, we outline several mitigation strategies reported in the literature. Furthermore, an economic analysis is also incorporated to assess the techno-economic viability and practical scalability of this technology. Finally, future perspectives are presented to highlight the important future considerations and provide a roadmap for this rapidly growing technology. By integrating these key aspects, this review shows a significant understanding of SFM double perovskite in CO₂ electrolysis in SOECs and highlights potential directions for future investigations and technological advancements.

Perovskite passivation plays a crucial role in achieving efficient perovskite solar cells (PSCs). A drawback of conventional perovskite passivation is the requirement of additional processes. However, spontaneous perovskite passivation using emerging alkyl-primary-ammonium bis(trifluoromethylsulfonyl)imides (RA-TFSIs) skips the additional processes, increasing the efficiency of PSC fabrication. During the deposition of the RA-TFSI additive-containing hole-transport material (HTM) solution, the RA cations spontaneously passivate the perovskite, exploiting the high adsorption energy of the RA cations on the perovskite surface. Moreover, RA-TFSIs replace the commonly used Li-TFSI, circumventing the use of detrimental Li species. However, RA-TFSIs are nascent; hence, further exploration of their composition and functions is imperative. In particular, the compatibility of HTMs with perovskite passivators comprising long aliphatic chains—not limited to RA-TFSIs—has been scarcely investigated. In this study, a newly synthesized dodecylammonium-TFSI (DDA-TFSI) spontaneous perovskite passivator was validated. The DDA-TFSI HTM additive enhanced the photovoltaic (PV) performance by its spontaneous perovskite passivation effects, yielding a power-conversion efficiency of 21.9% with an open-circuit voltage of 1.14 V, which are relatively high for Li-free FAPbI₃-based PSCs without post-passivation treatment. Nevertheless, the DDA-TFSI HTM additive—even at the optimal amount—degraded the uniformity of spiro-OMeTAD HTM layers, presumably owing to excess reduction of the dipole of the perovskite surface. This work highlights the importance of compatibility between HTMs and perovskite passivator materials. Moreover, although discussions on such negative features regarding non-uniform HTM layers are prone to be avoided, this knowledge fills the gap in the PSC research field and will eventually advance PSCs further.

Developing economically viable and high-performance electrocatalysts for the hydrogen evolution reaction (HER) is crucial for achieving sustainable hydrogen production. However, achieving a combination of high catalytic activity and long-term stability remains a challenge. In this study, we report the development of hierarchically porous hollow Co–Ni doped carbon electrocatalysts synthesized via pyrolysis. The optimized CoNi-MOF@850 °C catalyst exhibited excellent HER kinetics in alkaline media, requiring only 148 mV overpotential at 10 mA cm⁻² with a Tafel slope of 65 mV dec⁻¹, surpassing the monometallic Co and Ni catalysts and approaching the performance of the commercial Pt/C (95 mV, 43 mV dec⁻¹). Notably, when employed in an AEM electrolyzer, the CoNi-MOF@850 °C catalyst maintained ∼96% potential retention over 100 h at 200 mA cm⁻², demonstrating an exceptional stability. The synergistic interaction between Co and Ni, combined with the hierarchical porous structure, enhances electronic conductivity, increases active site density, and facilitates efficient charge transfer, leading to the observed superior catalytic performance. These results demonstrate the potential of bimetallic MOF-derived catalysts as cost-effective and sustainable alternatives to noble-metal-based electrocatalysts for large-scale green hydrogen production technologies.

The low operational stability of perovskite solar cells, primarily caused by ion migration under photogenerated electric fields, remains one of the key barriers to their practical deployment. In the present paper, we report the results of a comparative study of the field-induced aging dynamics in lead iodide perovskite films with different univalent cation compositions: MAPbI₃, FAPbI₃, Cs_0.15FA_0.85PbI₃ and Cs_0.1MA_0.15FA_0.75PbI₃. By employing a complementary suite of techniques including IR s-SNOM, PL microscopy, SEM/EDX, and ToF-SIMS mapping, alongside AIMD simulations of hydrogen on the surface of FAPbI₃, we visualized the dynamic behavior of cations and anions during aging and identified the corresponding reaction products. The simulations revealed that surface-based hydrogen can destabilize the lattice by abstracting surface iodine, in agreement with experimentally observed degradation of FAPbI₃, where volatile species are produced. It is shown that the formamidinium cations have a significantly higher resistance to electric fields when compared to the methylammonium cations. Univalent cation induced phase segregation has been observed for multication perovskite films upon electric field exposure. The results obtained provide a deep insight into the mechanistic pathways of the electrodegradation of differently composed lead halide perovskites and pave the way for the rational design of a new generation of perovskite absorber materials that can resist electric field-induced damage.

The development of efficient, durable, and cost-effective electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is central to advancing electrochemical water splitting as a scalable platform for green hydrogen production. Among emerging candidates, bimetallic catalysts offer exceptional promise due to their tunable electronic structure, synergistic surface interactions, and rich redox chemistry. This review critically examines the latest advances in identifying and elucidating the real active sites in bimetallic systems, highlighting their dynamic evolution under operating conditions and their influence on catalytic performance. We explore how structural motifs, including atomically dispersed dual sites, alloyed nanophases, heterointerface, and core–shell architectures, govern activity and stability by modulating adsorption energetics, charge transfer, and lattice strain. Emphasis is placed on integrating in situ and operando spectroscopic techniques with theoretical tools, such as density functional theory (DFT) and machine learning-assisted modeling, to uncover mechanistic pathways and establish accurate structure–activity relationships. Distinguishing geometric versus electronic contributions to active site behavior, with comparisons across acidic, alkaline, and saline media, is given particular attention. By bridging experimental observations and theoretical predictions, this review provides a comprehensive framework for the rational design of bimetallic electrocatalysts tailored for high-efficiency water splitting, offering insights into overcoming current limitations and guiding future directions in renewable hydrogen technologies.