Efficient H2O/CO2 co-electrolysis with NixCu1-x alloy nanocatalysts modified perovskite-type titanate cathodes

Syngas , a mixture of H 2 and CO with adjustable compositional ratios, can be directly produced via H 2 O/CO 2 co-electrolysis in solid oxide electrolysis cells (SOECs). In this study, We have developed a strategy to enhance the catalytic activity of titanate perovskite cathodes by constructing active metal-oxide interfaces through the in-situ growth of Ni x Cu 1-x alloy nanocatalysts (x = 0, 0.25, 0.5, 0.75 and 1) on LST matrix. The evenly distribution of Ni x Cu 1-x alloy nanoparticles (∼30 nm) on the LST substrate has been confirmed through a serious of characterization techniques, including XRD , XPS, SEM and TEM. Specifically, the LSTNi 0.75 Cu 0.25 cathode demonstrated an optimal synergistic effect , achieving high efficiency in the co-electrolysis of H 2 O/CO 2 to syngas. Under an applied voltage of 1.6 V at 800 °C, the syngas production rate reaches 5.43H 2 and 3.48 CO ml min −1 cm −2 with ∼96 % Faradaic efficiency. Furthermore, the composition of the produced syngas can be finely tuned in a broad range from 0.8 to 3.5 b y simply adjusting the inlet gas composition (H 2 O/CO 2 ratio) and the operating temperature. The LSTNi 0.75 Cu 0.25 cathode, when subjected to continuous H 2 O/CO 2 co-electrolysis for 100 h, exhibited remarkable stability, attributing to the robust and active nature of the metal-oxide interfaces.