AI 中文总结
研究磷掺杂和氧空位对CeO₂(111)上甲醛氧化的影响，用密度泛函理论模拟发现二者协同可增强HCHO吸附、降低C - H键裂解势垒、加速氧化及利于产物脱附，突出磷掺杂CeO₂(111)在低温HCHO氧化上的潜力并为催化材料设计提供见解。
AI 中文摘要
采用静态和动态密度泛函理论模拟相结合的方法，系统研究了CeO₂(111)表面的磷掺杂和氧空位如何影响甲醛(HCHO)的氧化机制。结果表明，P阳离子(P⁵⁺)取代晶格中的Ce⁴⁺，形成Ce - O - P键，降低带隙并通过电荷重新分布产生局域化的Ce³⁺态。磷掺杂与氧空位的协同效应增强了HCHO吸附，降低了C - H键裂解势垒，加速了甲醛氧化，且产物脱附快有利于催化剂再生。这些发现突出了磷掺杂的CeO₂(111)在低温HCHO氧化方面的潜力，并为二氧化铈基催化材料设计提供了见解。
英文摘要
Using a combination of static and dynamic density functional theory simulations, we systematically investigated how phosphorus doping and oxygen vacancies on the CeO$_2$(111) surface influence the oxidation mechanisms of formaldehyde (HCHO). Our results reveal that P cations (P$^{5+}$) substitutionally replace Ce$^{4+}$ in the lattice, forming Ce$-$O$-$P bonds that reduce the band gap (from 2.26 eV to 2.09 eV) and generate localized Ce$^{3+}$ states through charge redistribution. This synergistic effect of P doping combined with oxygen vacancy strengthens HCHO adsorption by decreasing the adsorption energy from -0.62 eV on pristine CeO$_2$(111) to -2.65 eV on the defective P-doped surface. Importantly, P doping lowers the C$-$H bond cleavage barrier by 0.84 eV relative to pristine CeO$_2$(111), accelerating formaldehyde oxidation on the defective surface. In addition, the rapid desorption of CO$_2$ and H$_2$O ($τ\sim 0.59 s$ at 300 K) indicates weak product-surface interactions, which favor efficient catalyst regeneration during continuous operation. These findings highlight P-doped CeO$_2$(111) as a promising system for low-temperature HCHO oxidation and provide insights into the design of ceria-based catalytic materials.
