Zirconia as a polycrystalline catalyst can be effectively tuned by doping low-valence elements and meanwhile form abundant oxygen vacancies. Herein, the crystalline structures of zirconia are modulated by scandium doping and proposed as a robust catalyst for nitrate reduction to ammonia. The tetragonal zirconia achieves a maximum ammonia yield of 16.03 mg h⁻¹ mg_cat.⁻¹, superior to the other crystal forms. DEMS tests unveil the reaction pathway and theoretical calculations reveal the low free energy of −0.22 eV for nitrate adsorption at the tetragonal zirconia.

中文翻译：

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氧化锆的晶体调节可在环境条件下有效地将硝酸盐还原为氨

氧化锆作为多晶催化剂，可以通过掺杂低价元素进行有效调控，同时形成丰富的氧空位。在此，氧化锆的晶体结构通过钪掺杂进行调节，并被提议作为硝酸盐还原成氨的强大催化剂。四方氧化锆的最大氨产量为 16.03 mg h ^-1 mg _cat。^-1，优于其他晶型。 DEMS 测试揭示了反应途径，理论计算揭示了四方氧化锆上硝酸盐吸附的低自由能 -0.22 eV。