Solid oxide electrolysis cells (SOECs) have received widespread attention due to their high efficiency, greenness and flexibility. SOECs produce value-added chemicals by electrocatalytically reducing CO2, which is of great significance for achieving CO2 reduction and renewable energy storage. This review first comprehensively explains the mechanism of SOEC electrolysis of CO2, followed by a detailed introduction to the classification and synthesis strategies of electrolyte, cathode and anode materials, including the microstructure design of electrodes. The reasons for SOEC performance degradation and countermeasures are discussed next. The related economic benefits of SOEC are also introduced. Finally, the challenges and prospects that SOEC needs to face for further technological utilization and commercialization are summarized.

The solid-state electrolyte is an important component of solid-state batteries and significantly influences the performance of batteries. However, pure solid-state polymer electrolyte has challenges such as low ionic conductivity, weak mechanical strength and poor ability to inhibit lithium dendrites. Therefore, a unique nano porous structural material based on a metal-organic framework (MOF) was proposed as a filler to enhance the polymer electrolyte, which is lithium ionic liquid (Li-IL) immersed into the MIL-125 framework to transform MIL-125 from an inert conductor to an efficient ionic conductor to obtain MIL-125-Li. MIL-125-Li not only has Lewis acid nature, but also provides a more definite and continuous transport pathway for the rapid migration of Li+. The composite polymer electrolytes (CPEs), containing 15 wt% of MIL-125-Li, exhibit an ionic conductivity of 3.9 x 10(-4) S cm(-1) at 28 degrees C. Furthermore, the CPEs demonstrate excellent interfacial stability with the lithium metal electrode, effectively inhibiting the growth of lithium dendrites. The assembled symmetric Li/PL-15 % MIL-125/Li battery can be stably cycled for more than 700 h at 0.1 mA cm(-2) at 28 degrees C. Applying the composite polymer electrolyte to LiFePO4/Li batteries, the discharge specific capacity achieves similar to 130 mAh g-l with a capacity retention rate of 83.9 % after cycling for 500 cycles at 0.5C. This simple modification method provides a novel design idea for all solid-state lithium batteries with excellent electrochemical performance.

Solid polymer electrolytes (SPEs) present substantial potential in the use of solid-state lithium batteries; however, their authentic usability is presently curbed by inadequate ionic conductivity and restricted lithium-ion mobility. Herein,...

LSCM perovskite is a promising ceramic cathode for direct CO2 electrolysis in solid oxide electrolysis cells (SOECs), but its application is limited by insufficient catalytic activity and stability. Herein, a novel strategy is proposed to improve electrolysis properties by modifying La0.75Sr0.25Cr0.5Mn0.5O3-delta-Gd0.2Ce0.8O2-delta (LSCM-GDC) backbone with Cu nanocatalyst. The metal-oxide interfaces between Cu NPs and ceramic backbone effectively increase the catalytic active sites and oxygen vacancy concentration, thus facilitating CO2 transport and reduction process. Consequently, Cu decorated cells achieve a peak current density of 1.33 A cm(-2) (2 wt%) at 800 degrees C and 1.5 V, which is 2.5 times that of the bare LSCM-GDC electrode (0.53 A cm(-2)). Similarly, R-p value is considerably decreased by 70% at 800 degrees C from 2.20 omega cm(2) to 0.65 omega cm(2). Overall, decoration with Cu nanocatalyst provides new insights for LSCM based cathodes. Graphical abstract

Solid polymer electrolytes (SPEs) present substantial potential for use in solid-state lithium batteries; however, their authentic usability is presently curbed by their inadequate ionic conductivity and restricted lithium-ion mobility. Herein, a strategy to enhance the performance of poly(vinylidene fluoride) (PVDF) composite polymer electrolytes (CPEs) using two-dimensional cobalt-based ultrathin metal-organic framework nanosheet (CMS) with a high aspect ratio is proposed. At a CMS loading of 8 wt%, the obtained CPEs displayed a high ionic conductivity of 6.26 x 10-4 S cm-1 (28 degrees C). In addition, the Li+ transfer number and electrochemical window were significantly improved. At 28 degrees C and 0.1 mA cm-2, the Li symmetric cells exhibited a long lifespan and stable cycling for over 750 h. An assembled all-solid-state Li/LiFePO4 cell displayed an ultrahigh capacity retention of 99.92% after 650 cycles at 0.5C and also demonstrated stable cycling performance at 1C. Moreover, the cycle performance of the Li/NCM811 cells was improved. The working mechanism of the CMS in CPEs was elucidated by density functional theory (DFT) calculations. These results emphasize that this novel electrolyte has unique characteristics and offers the potential for high-performance use in practical solid-state batteries. Solid polymer electrolytes (SPEs) present substantial potential for use in solid-state lithium batteries; however, their authentic usability is presently curbed by their inadequate ionic conductivity and restricted lithium-ion mobility.

The double-doped perovskite La0.75Sr0.25Cr0.5Mn0.5O3-5 (LSCM) is a promising cathode material for solid oxide electrolysis cells (SOECs), but the poor catalytic activity limits its application. In this work, LSCM-Gd0.2Ce0.8O2-5 (GDC) bilayer cathodes are successfully prepared for high temperature steam electrolysis. The moderate addition of GDC to LSCM electrode improves the cell performance due to the formation of more oxygen vacancies and increased H2O adsorption capability. Moreover, particle size graded cathodes are further prepared based on the optimal composition, and the optimized cell achieves a remarkable current density of 2.36 A cm-2 at -0.1 V and 800 degrees C under non-reducing conditions. The well-connected and porous network effectively extends the length of triplephase boundaries (TPBs) and facilitates the gas diffusion inside the electrode. Therefore, doping with a certain amount of GDC and optimizing the microstructure of electrodes are effective ways to enhance the electrocatalytic activity of the conventional LSCM-GDC cathode.(c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

固体氧化物电解池可以清洁、高效地将电能和热能转化为化学能,在新能源领域具有广阔的应用前景.La0.75 Sr0.25 Cr0.5 Mn0.5 O3-δ(LSCM)具有较好的高温稳定性,但离子电导率相对较低,在电解过程中电催化性能不足.本文将LSCM与具有较高离子导电性的Ce0.8 Gd0.2 O2-δ(GDC)复配构造复合电极,并以共负载的形式在复合电极中浸渍纳米Ni、Cu金属催化剂提高电极的水蒸气吸附和转化能力,Ni、Cu共负载能够同时保留单一Ni或Cu负载对电极电解机制的改善.结果表明,Ni、Cu共负载相比于单一Ni或Cu负载电极在还原性气氛下具有更高的电化学性能,在还原性气氛和800℃工作温度下,镍铜质量比2:8的负载电极在-0.1 V过电位下的电流密度可达到2.36 A·cm-2,极化阻抗为0.92Ω·cm2.

Co3FePx/C nanocomposites were derived from one-step phosphorization of anthraquinone-2-sulfonate (AQS2) intercalated Co3Fe layered double hydroxides (Co3Fe LDHs). The carbonized AQS2 confines Co3FePx nanoparticles in the amorphous carbon matrix during thermal treatment. Ultra-small and uniformly distributed Co3FePx/C nanoparticles in carbon exhibit excellent durability and outstanding OER catalytic activity.

The development of novel materials for environmentally friendly and high-energy-density storage devices is important for a sustainable future. Herein, we demonstrate that binder-free Fe-doped CoP nanowire arrays/carbon cloth (Fe-CoP/CC) anode for lithium-ion batteries (LIBs) can be successfully synthesized via a simple hydrothermal process combined with low-temperature phosphorization treatment. Structural characterizations show that Fe-CoP nanowires have a mean diameter of about 100 nm and an average length of about 5 mu m. As-prepared Fe-CoP/CC presented obviously enhanced electrochemical properties over those of pristine CoP/CC, including high specific capacity up to 1320.7 mAh g(-1) at 200 mA g(-1), good stability with retention of 76.5% after 140 cycles, and superior rate capability of 525.3 mAh g(-1) at 2 A g(-1). The excellent electrochemical properties can be ascribed to the special ID nanowire architecture, the in situ growth on conductive CC for a freestanding anode, as well as the synergy and complementarity of Co and Fe ions. These results indicate that as prepared Fe-CoP/CC is anticipated to be used in high-performance flexible LIBs and next-generation wearable energy storage systems.