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The solid oxide electrolysis cell (SOEC) is generally recognized as the optimal electrochemical conversion device for CO2 reduction reaction due to its high efficiency. However, the development of SOECs is limited by the lack of cathode materials with high electrocatalytic activity and stability. Perovskite cathodes exhibit redox stability at high temperatures, but their electrocatalytic activity remains limited. In this study, both A-site defects and B-site doping are designed for the perovskite La0.5Sr0.5TiO3−δ. This cathode material promotes B-site exsolution through A-site defects, resulting in high-density nanoparticles. The in situ exsolved nanoparticles and the oxide substrate form a metal–oxide interfacial structure that significantly enhances the electrocatalytic activity and stability of the SOEC cathodes. The La0.45Sr0.45Ti0.9Mn0.1Fe0.1O3−δ cathode exhibits exceptional electroreduction performance under the operating conditions of 850 °C, producing a CO yield of 5.3 mL min−1 cm−2 with a current efficiency of 97.1%. Even after 100 h of operation, the SOEC maintains excellent durability. This work provides new ideas for improving surface and interface engineering. [ABSTRACT FROM AUTHOR]

Microfluidics is of great interest for nano‐/micro‐fabrication but is conventionally limited inside microchannels. Breaking this restriction and developing 2D‐microfluidics is anticipated to expand the potential of microfluidics. Here, by harnessing the capillary effect of porous battery separator, a concept of self‐assembling capillary 2D‐microfluidics is proposed to achieve well‐controlled functional coating onto the separator thin‐film. The capillary‐assisted liquid tailoring behavior of this 2D‐microfluidics is investigated by both experimental and simulation studies, and the capillary number is found as the key parameter controlling the 2D‐micofluid thickness. For application studies, zein protein solution is employed for this 2D‐microfluidics to generate electrochemical active and self‐assembled protein microsphere coating onto the separator after drying. The resultant protein microsphere functionalized separator (PMFS) can physiochemically stabilize the surface of lithium metal anode. First, the PMFS works as spherical template to regulate uniform deposition of lithium ions. Second, similar to sustained drug release, the PMFS releases dissolved protein as functional additive into liquid electrolyte, assisting to form robust solid‐electrolyte‐interphase with highly conductive Li–C–N component. This work not only proposes a facile self‐assembling 2D‐microfluidic technology for surface nano‐/micro‐fabrication, but also brings forth a promising protein‐based physicochemical strategy for stabilizing lithium metal anode. [ABSTRACT FROM AUTHOR]

Achieving solid polymer electrolytes with ceramic‐like fast single‐ion conduction behavior, separator‐required mechanical properties, and good lithium‐dendrite suppression capability is essential but extremely challenging for the practical success of solid‐state lithium‐metal batteries. The key to overcome this long‐standing bottleneck is to rationally design the Li+‐transport microenvironment inside the polymeric ion‐conductors. Herein, the concept of a nano‐dipole doped composite polymer electrolyte (NDCPE) is proposed using surface‐charged halloysite nanotubes (d‐HNTs) as the dopant to achieve a Li+‐transport‐friendly microenvironment in poly(vinylidene fluoride) (PVDF) based quasi‐solid electrolytes. Results show that the d‐HNTs doping can immobilize the anions and help dissociate the lithium salt, which leads to an advanced dynamic Li+‐interface yielding both a high Li+‐transference number (0.75 ± 0.04) and ionic conductivity (0.29 ± 0.04 mS cm−1 @R.T.). Moreover, compared with the commercial separator, the NDCPE thin‐film shows similar toughness, mechanical strength, and puncture resistance, but much superior capability for stabilizing the lithium‐metal anode. To understand the possible doping mechanism, a hybrid Li+‐solvation model combining the surface charges of the nanofiller, absorbed solvent molecules, and absorbed polymer chain unit is proposed and discussed for guiding the future studies on advanced hybrid solid polymer electrolytes. [ABSTRACT FROM AUTHOR]

To overcome the critical safety and performance issues of lithium metal batteries, it is urgent to develop advanced electrolytes with multi‐defensive properties against fire, mechanical puncture, and dendrite growth simultaneously, in addition to high ion‐conductivity. However, realizing these essential properties by one electrolyte has proved to be extremely challenging due to the inherent conflicts among them. Herein, to circumvent this challenge, a neuron‐like gel polymer electrolyte (simply referred as Neu‐PE) to simultaneously achieve supertoughness, nonflammability, dendrite‐suppression capability and self‐driven property is reported. This Neu‐PE takes advantage of nano‐phase separation regulated by highly ion‐conductive deep‐eutectic solvent. As a result, the Neu‐PE holds high ambient ionic conductivity (1.27±0.09 mS cm−1), super‐toughness and strength (22.52 MJ m−3 and 13.5±0.6 MPa), fire resistance and importantly, lithium‐metal anode protection capability. Lithium metal batteries assembled with this multi‐defensive Neu‐PE can work normally even under metal‐probe puncture or serious damage by cutting. [ABSTRACT FROM AUTHOR]

Poly(ethylene oxide)‐based polymer all‐solid‐state LiS battery is a promising candidate due to its high specific energy, good processability, and low cost. However, the poor room temperature ionic conductivity limits its further development. Here an innovative photothermal battery technology is proposed to realize the normal operation at room temperature. This design places the 3D Cu substrate with Cu/Si core‐shell structures between Li anode and outer encapsulation glass, so that the light can come in and generate heat efficiently by utilizing the carrier nonradiative recombination of Si nano shell, then the heat quickly transfers to the battery system through Cu core. Once simulated sunlight irradiates, the battery achieves a fast reaction kinetics and superior photothermal conversion, thus realizing a lifespan of over 20 cycles with a capacity of 1089.9 mAh g−1 at 0.2 C. Even on the actual sunlight irradiation, a high discharge/charge capacity of 1065.2/1036.5 mAh g−1 is also reached, indicating an excellent reversible electrochemical process. Moreover, the 3D nanostructure can accommodate the fatal volume variation of lithium and reduce the effective current density, thus suppressing the dendrite nucleation and growth. This study will open the avenue to develop a room temperature polymer all‐solid‐state LiS battery using photothermal technology. [ABSTRACT FROM AUTHOR]

Conventional metal and cermet cathodes are easily oxidized during CO2 electrolysis, which seriously affects the electrolysis performance of electrolysis cells. The excellent durability and low cost of ceramic cathodes make them a promising alternative electrode. However, their catalytic activity is limited. In this work, we prepared a series of perovskite materials La0.6Sr0.4Cr1−xFexO3−δ (LSC1−xFx, x = 0–1) by synergistic doping at the B site to improve the catalytic activity. Replacing Cr with Fe can increase the concentration of low-valent Fe ions linked to oxygen vacancies, which leads to an increase in oxygen vacancies and thus improves the activity of CO2 electrolysis. Among the LSC1−xFx (x = 0–1) cathode materials, the LSC0.25F0.75 sample exhibits the highest electrochemical catalytic activity with a CO production rate of 5.32 mL min−1 cm−2 at 1.6 V and 850 °C, which is about 5 times that of other LSC cathode materials. In addition, its current efficiency can reach 96.4% during electrolysis of CO2. The electrolytic performance remained stable during the high temperature test for up to 100 h, further demonstrating its excellent thermal stability. [ABSTRACT FROM AUTHOR]

With an extremely high theoretical energy density, poly(ethylene oxide) (PEO)-based solid-state lithium-sulfur (Li-S) batteries are emerging as one of the most feasible and safest battery storage systems. However, the long-term cycling performance is severely impeded by polysulfides (Li 2 S n , n = 4-8) shuttling and terrible electrode passivation from the electronic insulating Li 2 S. Here, a novel cathode through chemically grafted 1-Ethyl-3-methylimidazolium bromide (EMIM + -Br - ) to carbon nanotube (CNTs) for PEO-based Li-S batteries is reported (CNTs@EMIM-Br/S). Concretely, bi-functional mediator EMIM + -Br - not only inhibits the polysulfides shuttling by strong chemical interactions via EMIM + , but also facilitates the electrochemical kinetics for promoting the formation of 3D particulate Li 2 S through high donor anion (Br - ). Satisfactorily, dual-function CNTs@EMIM-Br/S cathode exhibits high sulfur utilization with the capacity of up to 1298 mAh g -1 , and keeps high capacity retention of 80.2% at 0.2 C after 350 cycles, exceeding that of many reported PEO-based solid-state Li-S batteries. This work will open a new door for rationally designed architecture to enable the practical applications of advanced Li-S batteries., (© 2022 Wiley-VCH GmbH.)