• Energy Research
• Carbon Energy close

AbstractSolid‐state electrolytes (SSEs), being the key component of solid‐state lithium batteries, have a significant impact on battery performance. Rational materials structure and composition engineering on SSEs are promising to improve their Li+ conductivity, interfacial contact, and mechanical integrity. Among the fabrication approaches, the electrospinning technique has attracted tremendous attention due to its own merits in constructing a three‐dimensional framework of SSEs with precise porosity structure, tunable materials composition, easy operation, and superior physicochemical properties. To this end, in this review, we provide a comprehensive summary of the recent development of electrospinning techniques for high‐performance SSEs. Firstly, we introduce the historical development of SSEs and summarize the fundamentals, including the Li+ transport mechanism and materials selection principle. Then, the versatility of electrospinning technologies in the construction of the three main types of SSEs and stabilization of lithium metal anodes is comprehensively discussed. Finally, a perspective on future research directions based on previous work is highlighted for developing high‐performance solid‐state lithium batteries based on electrospinning techniques.

AbstractDesigning novel nonfullerene acceptors (NFAs) is of vital importance for the development of organic solar cells (OSC). Modification on the side chain and end group are two powerful tools to construct efficient NFAs. Here, based on the high‐performance L8BO, we selected 3‐ethylheptyl to substitute the inner chain of 2‐ethylhexyl, obtaining the backbone of BON3. Then we introduced different halogen atoms of fluorine and chlorine on 2‐(3‐oxo‐2,3‐dihydro‐1H‐inden‐1‐ylidene) malononitrile end group (EG) to construct efficient NFAs named BON3‐F and BON3‐Cl, respectively. Polymer donor D18 was chosen to combine with two novel NFAs to construct OSC devices. Impressively, D18:BON3‐Cl‐based device shows a remarkable power conversion efficiency (PCE) of 18.57%, with a high open‐circuit voltage (VOC) of 0.907 V and an excellent fill factor (FF) of 80.44%, which is one of the highest binary PCE of devices based on D18 as the donor. However, BON3‐F‐based device shows a relatively lower PCE of 17.79% with a decreased FF of 79.05%. The better photovoltaic performance is mainly attributed to the red‐shifted absorption, higher electron and hole mobilities, reduced charge recombination, and enhanced molecular packing in the D18:BON3‐Cl films. Also, we performed stability tests on two binary systems; the D18:BON3‐Cl and D18:BON3‐F devices maintain 88.1% and 85.5% of their initial efficiencies after 169 h of storage at 85°C in an N2‐filled glove box, respectively. Our work demonstrates the importance of selecting halogen atoms on EG and provides an efficient binary system of D18:BON3‐Cl for further improvement of PCE.

AbstractIn recent years, renewable energy sources, which aim to replace rapidly depleting fossil fuels, face challenges due to limited energy storage and conversion technologies. To enhance energy storage and conversion efficiency, extensive research has been conducted in the academic community on numerous potential materials. Among these materials, metal fluorides have attracted significant attention due to their ionic metal–fluorine bonds and tunable electronic structures, attributed to the highest electronegativity of fluorine in their chemical composition. This makes them promising candidates for future electrochemical applications in various fields. However, metal fluorides encounter various challenges in different application directions. Therefore, we comprehensively review the applications of metal fluorides in the field of energy storage and conversion, aiming to deepen our understanding of their exhibited characteristics in different electrochemical processes. In this paper, we summarize the difficulties and improvement methods encountered in different types of battery applications and several typical electrode optimization strategies in the field of supercapacitors. In the field of water electrolysis, we focus on surface reconstruction and the critical role of fluorine, demonstrating the catalytic performance of metal fluorides from the perspectives of reconstruction mechanism and process analysis. Finally, we provide a summary and outlook for this field, aiming to offer guidance for future breakthroughs in the energy storage and conversion applications of metal fluorides.

AbstractCoupling together the ferroelectric, pyroelectric, and photovoltaic characteristics within a single material is a novel way to improve the performance of photodetectors. In this work, we take advantage of the triple multifunctionality shown by 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 (BCZT), as demonstrated in an Al/Si/SiOx/BCZT/ITO thin‐film device. The Si/SiOx acts as an n‐type layer to form a metal–ferroelectric–insulator–semiconductor heterostructure with the BCZT, and with Al and ITO as electrodes. The photo‐response of the device, with excitation from a violet laser (405 nm wavelength), is carefully investigated, and it is shown that the photodetector performance is invariant with the chopper frequency owing to the pyro‐phototronic effect, which corresponds to the coupling together of the pyroelectric and photovoltaic responses. However, the photodetector performance was significantly better than that of the devices operating based only on the pyro‐phototronic effect by a factor of 4, due to the presence of ferroelectricity in the system. Thus, after a poling voltage of −15 V, for a laser power density of 230 mW/cm2 and at a chopper frequency of 400 Hz, optimized responsivity, detectivity, and sensitivity values of 13.1 mA/W, 1.7 × 1010 Jones, and 26.9, respectively, are achieved. Furthermore, ultrafast rise and fall times of 2.4 and 1.5 µs, respectively, are obtained, which are 35,000 and 36,000 times faster rise and fall responses, respectively, than previous reports of devices with the ferro–pyro–phototronic effect. This is understood based on the much faster ferroelectric switching in ferroelectric thin films owing to the predominant 180° domains in a single direction out of plane.

AbstractRuthenium (Ru) has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction (HER), owing to its inherent high activity and being the cheapest platinum‐group metal. Herein, based on the idea of strong metal–support interaction (SMSI) regulation, Ru/TiN catalysts with different degrees of TiN overlayer over Ru nanoparticles were fabricated, which were applied to the alkaline electrolytic water. Characterizations reveal that the TiN overlayer would gradually encapsulate the Ru nanoparticles and induce more electron transfer from Ru nanoparticles to TiN support by the Ru–N–Ti bond as the SMSI degree increased. Further study shows that the exposed Ru–TiN interfaces greatly promote the H2 desorption capacity. Thus, the Ru/TiN‐300 with a moderate SMSI degree exhibits excellent HER performance, with an overpotential of 38 mV at 10 mA cm−2. Also, due to the encapsulation role of TiN overlayer on Ru nanoparticles, it displays super long‐term stability with a very slight potential change after 24 h. This study provides a deep insight into the influence of the SMSI effect between Ru and TiN on HER and offers a novel approach for preparing efficient and stable HER electrocatalysts through SMSI engineering.

AbstractPotassium‐ion batteries (PIBs) offer a cost‐effective and resource‐abundant solution for large‐scale energy storage. However, the progress of PIBs is impeded by the lack of high‐capacity, long‐life, and fast‐kinetics anode electrode materials. Here, we propose a dual synergic optimization strategy to enhance the K+ storage stability and reaction kinetics of Bi2S3 through two‐dimensional compositing and cation doping. Externally, Bi2S3 nanoparticles are loaded onto the surface of three‐dimensional interconnected Ti3C2Tx nanosheets to stabilize the electrode structure. Internally, Cu2+ doping acts as active sites to accelerate K+ storage kinetics. Various theoretical simulations and ex situ techniques are used to elucidate the external–internal dual synergism. During discharge, Ti3C2Tx and Cu2+ collaboratively facilitate K+ intercalation. Subsequently, Cu2+ doping primarily promotes the fracture of Bi2S3 bonds, facilitating a conversion reaction. Throughout cycling, the Ti3C2Tx composite structure and Cu2+ doping sustain functionality. The resulting Cu2+‐doped Bi2S3 anchored on Ti3C2Tx (C‐BT) shows excellent rate capability (600 mAh g–1 at 0.1 A g–1; 105 mAh g–1 at 5.0 A g–1) and cycling performance (91 mAh g–1 at 5.0 A g–1 after 1000 cycles) in half cells and a high energy density (179 Wh kg–1) in full cells.