Sustainable Energy & Fuels最新文献

Mesoporous TiO₂ (mp-TiO₂), mesoporous ZrO₂ (mp-ZrO₂), and mesoporous carbon (mp-C) without a hole transport layer make up the triple-layer structure of printable mesoscopic perovskite solar cells (p-MPSCs), which have become an extremely promising next-generation photovoltaic technology given their low cost, simplicity of fabrication, and outstanding stability. However, the unique device structure of p-MPSCs requires perovskites to crystallize within a mesoscopic scaffold over ten micrometers thick, resulting in a more complex crystallization process than that in conventional perovskite solar cells, with greater challenges in crystallization control, smaller crystal grains and an increased number of grain boundaries. In this study, trifluoroacetamide (TFAA), containing amide groups, was introduced as an active layer additive to passivate perovskite defects and thus enhanced the performance and stability of p-MPSCs. The CO and –NH₂ groups in TFAA effectively passivate uncoordinated Pb²⁺ and I⁻ ions in the perovskite, enhancing film quality and significantly boosting light absorption. Additionally, TFAA incorporation reduced defect density, improved carrier extraction and transport, and strengthened the built-in electric field, resulting in a PCE of 18.67%. The presence of F⁻ also increased the hydrophobicity of the perovskite film, further improving air stability. Under dark conditions, unencapsulated p-MPSCs with TFAA retained 90% of their initial PCE after 62 days of storage in air (25 ± 5 °C, 40 ± 5% humidity), compared to 76% for untreated p-MPSCs.

Further enhancement of the energy density of lithium-ion batteries is a goal pursued in state-of-the-art batteries, and the use of thick electrodes is an effective and direct means. However, thick electrodes often suffer from severe electrochemical performance degradation, which severely hinders their practical application. We comprehensively review the latest progress in the field of thick electrodes to overcome the bottleneck of thick electrode development. First, we systematically analyzed the factors that cause the capacity failure of thick electrodes. The reaction heterogeneity caused by slow kinetics accelerates the deterioration of mechanical stability and interface. Next, we introduce mainstream strategies to enhance the performance of thick electrodes, including multi-scale structural designs from the particle to the electrode level aimed at improving the kinetic performance. However, these studies mainly focus on improving kinetic performance. By analyzing the real electrode reaction processes, we emphasize the critical role of thermodynamics in electrode reactions, suggesting that optimizing the thermodynamic properties can also enhance the performance of thick electrodes. Finally, we propose a development path for thick electrodes under the coupled design of kinetics and thermodynamics. This work offers a more comprehensive perspective to guide electrode design efforts.

Correction for ‘Photocatalytic CO₂ reduction to methanol integrated with the oxidative coupling of thiols for S–X (X = S, C) bond formation over an Fe₃O₄/BiVO₄ composite’ by Nitish Saini et al., Sustainable Energy Fuels, 2024, 8, 1750–1760, https://doi.org/10.1039/D3SE01651J.

This study unveils a highly efficient electrocatalyst based on hydrated ammonium metal phosphates (NH₄MPO₄·H₂O) with a layered crystal structure and expanded interlayer spacing, facilitating rapid electron and ion transport for advanced oxygen evolution reaction (OER) applications. Addressing inherent limitations in conductivity and electroactive surface area, we engineered a heterostructured electrocatalyst by combining NH₄NiPO₄·H₂O with CdIn₂S₄ and in situ formed Ni₃S₂ on nickel foam (NF) through a two-step hydrothermal process. The resulting NH₄NiPO₄·H₂O/CdIn₂S₄/Ni₃S₂ (NPO/CINS) system leverages phosphate–sulfide interfacial interactions, significantly enhancing catalytic performance. Electrochemical tests reveal impressive OER and urea oxidation reaction (UOR) activities, achieving low overpotentials of 245 mV and 1.26 V at 10 mA cm⁻², respectively. The obtained exceptional UOR efficiency exceeds that of previously reported oxide and sulfide-based heterostructure electrocatalysts. The NPO/CINS heterostructure demonstrates remarkable stability towards OER, with only 2% degradation over 65 hours of continuous operation, affirming its durability for high-performance applications. This work emphasizes the power of synergistic interfacial bonding, optimized electron transfer, and strategic structural design, positioning the NPO/CINS heterostructure as a pioneering catalyst for scalable energy solutions.

The electrochemical glycerol oxidation reaction (GOR) offers a dynamically favourable pathway to transform biomass byproducts into value-added chemicals such as formic acid, glycolic acid, glyceraldehyde, and glyceric acid. This approach offers a more efficient utilization of glycerol and might fulfil the anticipated future demands for formic acid, and which serves as a potential fuel for both direct and indirect formic acid fuel cells. However, the current challenge lies in the low oxidation activity and conversion ratio exhibited by existing catalysts. Herein, an amorphous Co₃O₄–CuO/CN_x-300 composite on a carbon cloth was fabricated, which shows high activity toward electrochemical glycerol oxidation with a very low potential of 1.25 V (RHE) at 10 mA cm⁻² and a very high faradaic efficiency of about 91% (formic acid = 81% and glycolic acid = 10%) at 1.5 V (RHE) potential for oxidative product formation with a high selectivity of 89% for formic acid production. Furthermore, the as-prepared Pt/C‖Co₃O₄–CuO/CN_x-300 electrolyzer required 260 mV less potential compared with conventional water splitting to achieve a current density of 10 mA cm⁻². In addition, the electrolyzer was stable at a cell potential of 1.7 V for up to 60 hours, reducing the energy consumption of traditional water splitting by ∼15.48%. The high GOR performance of Co₃O₄–CuO/CN_x-300 is attributed to the synergistic interaction between its components, its amorphous structure, and its high surface area. This study offers fascinating insights for designing cost-effective transition metal-based electrocatalysts, aiming to facilitate glycerol oxidation for the production of value-added chemicals while boosting efficient cathodic hydrogen evolution with minimal energy depletion.

Separators are known to be a mandatory component due to their crucial function in preventing short circuits between positive and negative electrodes, ensuring the safety and cycle life of energy storage devices. However, in practice, separators are a crucial component that affects cell electrochemical performance, especially rate capability and power density, which have been addressed in only a few research studies. To further investigate this topic, this study introduces durable and eco-friendly separators synthesised by hybridising bacterial cellulose (BC) and gelatin through a facile, cost-effective, desirable and environmentally friendly microbubble process. The as-fabricated symmetric supercapacitor with an as-synthesised separator, prepared under optimal conditions of 2 g per mL BC with 1.5 wt% gelatin and a microbubble rate of 200 CC per min (designated as 2BC1.5GT_R200), reduces cell resistance and optimises ion transport within the cell compared to as-fabricated symmetric supercapacitors using BC, hybridised BC–gelatin under other conditions, conventional cellulose and commercial separators. Additionally, symmetric devices with 2BC1.5GT_R200 separators achieve excellent capacitance retention across a wide range of electrolyte environments, including acidic (1 M H₂SO₄), basic (1 M KOH), and neutral (1 M NaNO₃) solutions, retaining over 91%, 87%, and 82% of their initial capacitance after 10 000 cycles, respectively. These data demonstrate that the microbubble synthesis process combined with gelatin hybridisation can maximise electrochemical performance, maintain high cell efficiency, and enable operation in diverse electrolytes, presenting a promising route for developing innovative separators for energy storage applications.

Photothermal catalysis has garnered significant attention as a potential solution to address energy scarcity. In photothermal catalysis, light irradiation directly heats the catalyst bed, inducing a localized temperature gradient. However, in methane reforming reactions such as dry reforming, the undesired reverse reaction typically proceeds in the lower temperature zone of the catalyst bed, which reduces the overall efficiency. To address this issue, we developed a novel flow-type photo-reactor composed of a quartz tube and a quartz filler welded within the tube. The narrow catalyst-filled gap was used for catalytic reaction that minimizes the temperature gradient under light irradiation. The developed reactor, termed the gap reactor, demonstrated excellent catalytic performance in photothermal dry reforming of methane (PT-DRM), achieving ∼70–80% conversion of CH₄ and CO₂ over 100 hours using a SiO₂-encapsulated Co–Ni alloy catalyst previously developed by our group. Compared to the conventional quartz tube reactor with the same cross-sectional area for light absorption, the gap reactor significantly enhanced both conversion and stability. Furthermore, integrating the gap reactor with steam addition to the reaction feed successfully suppressed coke formation to only 0.6 wt% after approximately 50 hours of reaction. This study highlights the benefits of the gap reactor design in high-temperature catalytic applications up to 1000 °C.

The electronic environment of metal–nitrogen/carbon catalysts derived from metal–organic frameworks (MOFs) strongly correlates with their catalytic performance in the oxygen reduction reaction (ORR). Here, we report a novel ligand displacement approach for exchanging the 2-methylimidazole (2-MI) ligand in zeolitic imidazolate framework-67 (ZIF-67) with mercapto-5-nitrobenzimidazole (MNBI), followed by pyrolysis at 800 °C to generate ZIF-67/MNBI-800 as a Co–N/C catalyst. The ligand displacement efficiently tuned the electronic environment of the Co center through different configurations of nitrogen and sulfur elements, thereby affecting the oxygen-binding force of the Co–N/C catalysts. Further acid etching eliminates the impact of symbiotic Co nanocrystal in raw ZIF-67/MNBI-800 catalysts, allowing the Co–N/C catalysts to achieve an exceptional performance. Acid etched ZIF-67/MNBI-800 (A-ZIF-67/MNBI-800) shows an optimal oxygen adsorption strength, of which the half-wave potential is 39 mV more positive, and mass activity increases by a factor of 5.9, as compared with the benchmark platinum catalyst. This impressive performance makes A-ZIF-67/MNBI-800 a robust air-breathing electrode for a rechargeable zinc–air battery that exhibits high peak power density (302.0 mW cm⁻²) and amazing cycle life (2220 cycles for 750 h of operation). This work provides a simple but effective approach for tuning the electronic density of metal centers and an in-depth insight into its correlation with catalytic properties, thereby paving the way for rational ORR catalyst design.

To improve the performance of direct ethanol fuel cells (DEFCs), which are hindered by traditional catalysts, having matters pertaining to stability, activity, and selectivity in reaction environments, various electrocatalysts such as Pd/Ni₂P, Pd/MoS₂, and Pd/Ni₂P–MoS₂ were synthesized using the microwave-assisted NaBH₄–ethylene glycol reduction method. The research findings suggest that the Pd/Ni₂P–MoS₂ catalyst we developed had the highest activity (1579 mA mg_Pd⁻¹), approximately 21 times greater than that of commercial Pd/C. The stability of the electrocatalysts were examined using chronoamperometry (CA) and cyclic voltammetry (CV) measurements, which indicated that the Pd/Ni₂P–MoS₂ electrocatalyst had good stability towards the ethanol oxidation reaction (EOR) in alkaline electrolyte. Electrochemical impedance spectroscopy (EIS) analysis showed that the Pd/Ni₂P–MoS₂ electrocatalyst had lower charge transfer resistance, indicating better electrochemical kinetics. According to XRD, HR-TEM, XPS, and electrochemical analysis, the enhanced electrocatalytic activity, long-term stability of the Pd/Ni₂P–MoS₂ electrocatalyst were attributable to the interface synergism as well as electronic and strain effects between the Pd, Ni₂P, and MoS₂ interactions. This resulted in a downshift in the d-band center of the Pd/Ni₂P–MoS₂ electrocatalyst, weakening intermediate adsorption and the adsorbate metal interaction.

Hole-transporting materials (HTMs) play a crucial role in perovskite solar cells (PSCs). Herein, we have designed and synthesized a new hole-transporting molecule, denoted as sp-35, from low-cost, commercially available reagents via a simple two-step synthesis route. The molecular architecture of sp-35 consists of a bifluorenylidene core moiety covalently linked with phenylfluorenamine units at the end. The suitable energy levels, ideal surface morphologies, high hole mobility of 2.388 × 10⁻³ cm² V⁻¹ s⁻¹, and stable chemical structure of sp-35 make it an effective HTM. As a result, PSCs constructed with sp-35 exhibit a high power conversion efficiency (PCE) of 21.59%, while spiro-OMeTAD shows a PCE of 20.42%. Promisingly, the device with sp-35 exhibits significantly better long-term and thermal stabilities than spiro-OMeTAD. This work presents a new molecular design and an in-depth understanding of the HTL strategy and its potential for the development of highly efficient cell performances.