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Urea synthesis through the simultaneous electrocatalytic reduction of N₂and CO₂molecules under ambient conditions holds great promises as a sustainable alternative to its industrial production, in which the development of stable, highly efficient, and highly selective catalysts to boost the chemisorption, activation, and coupling of inert N₂and CO₂molecules remains rather challenging. Herein, by means of density functional theory computations, we proposed a new class of two‐dimensional nanomaterials, namely, transition‐metal phosphide monolayers (TM₂P, TM = Ti, Fe, Zr, Mo, and W), as the potential electrocatalysts for urea production. Our results showed that these TM₂P materials exhibit outstanding stability and excellent metallic properties. Interestingly, the Mo₂P monolayer was screened out as the best catalyst for urea synthesis due to its small kinetic energy barrier (0.35 eV) for C–N coupling, low limiting potential (−0.39 V), and significant suppressing effects on the competing side reactions. The outstanding catalytic activity of the Mo₂P monolayer can be ascribed to its optimal adsorption strength with the key *NCON species due to its moderate positive charges on the Mo active sites. Our findings not only propose a novel catalyst with high‐efficiency and high‐selectivity for urea production but also further widen the potential applications of metal phosphides in electrocatalysis.

 

Metal oxide semiconductors have attracted much attention due to their versatility in different applications, ranging from biosensing to green energy-harvesting technologies. Among these metal oxides, oxide-based diluted magnetic semiconductors have also been proposed for fuel cell applications, especially for the oxygen reduction reaction (ORR) and the oxygen evolution reaction. However, the catalytic mechanism has been proposed to follow a two-electron pathway, forming hydrogen peroxide, instead of the four-electron pathway. Herein, we report cobalt-doped zinc oxide (CoxZn1–xO, 0 < x < 0.018) materials prepared using a co-precipitation method suitable for the electrocatalytic production of hydrogen peroxide. The electrocatalytic performance of CoxZn1–xO materials showed up to 60% hydrogen peroxide production with onset potentials near 649 mV, followed by the two-electron ORR mechanism. Ex situ X-ray absorption spectroscopy experiments at the Co K-edge demonstrated the presence of Co(II) ions at tetrahedral sites within the ZnO lattice.