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The in situ exsolution technique of nanoparticles has brought new opportunities for the utilization of perovskite‐based catalysts in solid oxide cells. However, the lack of control over the structural evolution of host perovskites during the promotion of exsolution has restricted the architectural exploitation of exsolution‐facilitated perovskites. In this study, we strategically broke the long‐standing trade‐off phenomenon between promoted exsolution and suppressed phase transition via B‐site supplement, thus broadening the scope of exsolution‐facilitated perovskite materials. Using carbon dioxide electrolysis as an illustrative case study, we demonstrate that the catalytic activity and stability of perovskites with exsolved nanoparticles (P‐eNs) can be selectively enhanced by regulating the explicit phase of host perovskites, accentuating the critical role of the architectures of perovskite scaffold in catalytic reactions occurring on P‐eNs. The concept demonstrated could potentially pave the way for designing the advanced exsolution‐facilitated P‐eNs materials and unveiling a wide range of catalytic chemistry taking place on P‐eNs. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of CO2 (CO2RR) is a versatile method that is capable of simultaneously reduce CO2 emission and produce valuable fuels and chemicals. However, its application is hindered by the lack of cost‐effective catalysts and significant overpotential requirement. In this work, we report a low‐cost and surfactant/capping agent free method to synthesize cubic Cu2O−SnO2 core‐shell electrocatalyst, whose thickness can be easily controlled by the content of tin precursor. The optimized Cu2O−SnO2 catalyst with a 5 nm‐thick shell achieved over 90 % faradaic efficiency towards CO at a low overpotential of 390 mV, which is comparable to some of the noble metal catalysts. The catalyst also exhibited good stability over 18 hours of test at −0.6 V vs. RHE in 0.5 M KHCO3 electrolyte. This work provides a widely applicable strategy for developing a low‐cost electrocatalyst for CO2 conversion. [ABSTRACT FROM AUTHOR]

Hydration properties and electrical characteristics of the hightemperature proton conductor La27(W0.85Nb0.15)5O55.5-δ are investigated by means of thermogravimetry, impedance spectroscopy, and the electromotive force (EMF) method as a function of temperature, water vapor, and oxygen partial pressures, as well as isotope exchange measurements in order to elucidate the mechanism and thermodynamics of protons formation and transport. The highest proton conductivity, 1.3 3 10-3 S/cm, is achieved at 700°C in wet O2. Proton selfdiffusion coefficients are estimated from thermogravimetric measurements of hydration and conductivity data. Comparison of the conductivity characteristics between nominally pure and Nb-substituted materials reveals that the ionic conductivity increases and the activation energy decreases with Nb doping. These differences are discussed to reflect changes in the structure promoting ionic transport rather than changing the concentration of defects to any large extent. [ABSTRACT FROM AUTHOR]

Hydration properties and electrical characteristics of the hightemperature proton conductor La27(W0.85Nb0.15)5O55.5-δ are investigated by means of thermogravimetry, impedance spectroscopy, and the electromotive force (EMF) method as a function of temperature, water vapor, and oxygen partial pressures, as well as isotope exchange measurements in order to elucidate the mechanism and thermodynamics of protons formation and transport. The highest proton conductivity, 1.3 3 10-3 S/cm, is achieved at 700°C in wet O2. Proton selfdiffusion coefficients are estimated from thermogravimetric measurements of hydration and conductivity data. Comparison of the conductivity characteristics between nominally pure and Nb-substituted materials reveals that the ionic conductivity increases and the activation energy decreases with Nb doping. These differences are discussed to reflect changes in the structure promoting ionic transport rather than changing the concentration of defects to any large extent. [ABSTRACT FROM AUTHOR]