In Situ Exsolution of Core‐Shell Structured NiFe/FeO_x Nanoparticles on Pr_0.4Sr_1.6(NiFe)_1.5Mo_0.5O_6‐δ for CO₂ Electrolysis

Abstract

Solid oxide electrolysis cells (SOECs) have potential for efficient conversionof CO 2 to valuable chemical fuels at low cost. However, the performance and commercial viability of the existing SOECs is still hindered by the poor durability and electro-catalytic activity of the cathode for CO 2 electrolysis. Here, the findings in preparation and characterization of a Ni-free SOEC cathode materials composed of a Pr 0.4 Sr 1.6 (NiFe) 1.5 Mo 0.5 O 6-δ (PSNFM) double perovskite matrix decorated with exsolved core-shell structured NiFe/FeO x (NFA@FeO) nanoparticles are reported. A single cell with the PSNFM-NFA@FeO cathode demonstrates a high current density of 1.58 A cm −2 for CO 2 electrolysis at a cell voltage of 1.4 V at 800 °C. The excellent electro-catalytic activity of PSNFM-NFA@FeO is attributed to the in situ exsolved NFA@FeO nanoparticles and the additional oxygen vacancies generated within the PSNFM substrate, creating plentiful NFA@FeO/PSNFM interfaces active for CO 2 adsorption and electrolysis. Moreover, the FeO shell on the NFA also contains a lot of oxygen vacancies, which can effectively extend the active sites from the NFA@FeO/ PSNFM interfaces to the entire surface of the NFA@FeO nanoparticles, greatly enhancing the kinetics of adsorption, dissociation, and reduction of CO 2 .

Recent advances in exsolved perovskite oxide construction: exsolution theory, modulation, challenges, and prospects

“…The perovskite with A-site deciency will return to the stoichiometric stable state aer the exsolution of B-site metal. The exsolution of ABO 3 -type perovskite is oen accompanied by the formation of the AO phase (see (8) and ( 9)), 25 and ( 8) is the exsolution process of A-site deciency.…”

“…5 The B-site active metal elements can be released from the lattice and anchored on the perovskite oxide surface by in situ exsolution under a reducing atmosphere, which has stronger stability and metaloxide interface interaction force. 6 This approach has been widely used in thermal catalysis, photocatalysis, 7 fuel cells, [8][9][10] and other elds, showing excellent catalytic performance and oxygen ion transfer capability. 7,11,12 Among them, nearly 70% of the studies on the exsolution of nonnoble metals are electrochemical applications.…”

A mini review of the recent progress of electrode materials for low-temperature solid oxide fuel cells

“…Tan et al 22 reported a Pr 0.4 Sr 1.6 (NiFe) 1.5 Mo 0.5 O 6− δ (PSNFM) double perovskite matrix decorated with exsolved core/shell structure NiFe/FeO x (NFA@FeO) nanoparticles. The micromorphological characterization is shown in Fig.…”

Emerging Exsolution Materials for Diverse Energy Applications: Design, Mechanism, and Future Prospects

“…Liu et al reported that a CoFe nanocatalyst exsolved from a double-layered perovskite scaffold improved the reversibility between the reduction and oxidation cycles. Furthermore, a NiFe alloy exhibited a higher coking resistance and redox stability than a single Ni catalyst, promoting the reaction kinetics for CO 2 electrolysis. , Noble-metal exsolution catalysts have been introduced to maximize the conversion efficiency and coking resistance . Kyriakou et al used Rh exsolution catalysts for coincident CO 2 –H 2 O coelectrolysis and CH 4 partial oxidation (Figure d,e).…”