Nitrogen-doped Zn–Ni oxide for electrochemical reduction of carbon dioxide in sea water

Nitrogen-doped Zn–Ni oxide nanoparticles prepared by ammonia treatment are efficient electrocatalysts for CO 2 reduction to CO. The single-phase nanostructures of N-Zn–Ni oxide nanoparticles exhibited high electrocatalytic CO 2 reduction activity with CO Faradaic efficiency of 91.5% and partial current density of 3.2 mA·cm −2 at − 0.95 V (vs. reversible hydrogen electrode‚ RHE) in NaCl aqueous solution. Furthermore‚ N-Zn–Ni oxides catalyst achieved CO Faradaic efficiency over 89% at − 0.8 V (vs. RHE) in natural seawater‚ much better than the CO 2 reduction activity of benchmark Ag/C catalysts in seawater‚ and demonstrated strong tolerance to several metal ion impurities with retained CO selectivity. The notable reactivity toward CO 2 reduction and contamination-tolerance is attributed to peculiar synergistic effect from binary Zn–Ni oxide and nitrogen doping. 摘要 通过氨气处理制备的氮掺杂Zn-Ni氧化物纳米颗粒是用于将CO2还原为CO的高效电催化剂。氮掺杂Zn-Ni氧化物纳米颗粒的单相纳米结构具有优异的电催化CO2还原活性, 在NaCl水溶液中, 该电催化材料在-0.95 V(相对于可逆氢电极)还原电位下, CO2电化学还原产生CO的法拉第效率为91.5%, CO分电流密度为3.2 mA•cm-2。在天然海水中, 氮掺杂Zn-Ni氧化物催化剂在-0.8 V(相对于可逆氢电极)还原电位下的CO法拉第效率高达89%, 远高于基准Ag / C催化剂在海水中的电催化CO2还原活性, 该材料对于金属离子杂质的耐受性强, 在含有不同金属离子杂质的电解液中仍展现了较高的CO2电化学还原为CO的选择性。出色的CO2还原电催化活性和良好的杂质离子耐受性可能归因于二元Zn-Ni氧化物和氮掺杂特殊的协同作用。 Graphical Abstract