论文标题
揭示碳缺陷在M-ZRO2带隙的特殊狭窄中的作用，以增强光电化学水分分裂性能
Unveiling the role of carbon defects in the exceptional narrowing of m-ZrO2 bandgap for enhanced photoelectrochemical water splitting performance
论文作者
论文摘要
多年来，通过宽带间隙金属氧化物的缺陷工程开发有效的光电塑像一直是主要的重点。具体而言，宽带间隙金属氧化物中碳缺陷对光电化学（PEC）应用的性能的影响引起了许多争议，但仍然难以捉摸。在此，使用密度功能理论研究了M-ZRO2中各种碳缺陷的影响，以探测有缺陷结构对原始M-Zro2的热力学，电子和光学性质。缺陷形成能表明，升高温度会促进并促进碳缺陷的形成。此外，结合能证实了所有研究的复杂碳缺陷的稳定性。此外，对水物种的氧化还原电势的带边缘位置表明，所有研究的缺陷结构都可以用作水分分流的光阳极。此外，CO3C（碳原子取代的O3C位点）是唯一显示出水的氧化还原电位略微跨越的有缺陷的结构。重要的是，所有研究的有缺陷的结构都通过不同的光学活性增强了光吸收。最后，CO3CVO3C（碳原子取代与O3C空位相关的O3C）有缺陷的M-ZRO2具有低直的带隙（1.9 eV），低缺陷形成能，低激子结合能，电荷载体的高迁移率，高电荷转移和低重组率。同时，其光学特性在高吸收，低反射率和改善的静态介电常数方面是非凡的。因此，该研究建议CO3CVO3C有缺陷的M-ZRO2作为PEC应用光阳极的主要候选人。
The development of efficient photoelectrodes via defect engineering of wide-band gap metal oxides has been the prime focus for many years. Specifically, the effect of carbon defects in wide-band gap metal oxides on their performance in photoelectrochemical (PEC) applications raised numerous controversies and still elusive. Herein, the effect of various carbon defects in m-ZrO2 was investigated using the density functional theory to probe the thermodynamic, electronic, and optical properties of the defective structures against pristine m-ZrO2. The defect formation energies revealed that elevating the temperature promotes and facilitates the formation of carbon defects. Moreover, the binding energies confirmed the stability of all studied complex carbon defects. Furthermore, the band edge positions against the redox potentials of water species revealed that all the studied defective structures can serve as photoanodes for water splitting. Additionally, CO3c (carbon atom substituted O3c site) was the only defective structure that exhibited slight straddling of the redox potentials of water. Importantly, all investigated defective structures enhanced light absorption with different optical activities. Finally, CO3cVO3c (carbon atom substituted O3c associated with O3c vacancy) defective m-ZrO2 enjoyed low direct band gap (1.9 eV), low defect formation energy, low exciton binding energy, high mobility of charge carriers, fast charge transfer, and low recombination rate. Concurrently, its optical properties were exceptional in terms of high absorption, low reflectivity and improved static dielectric constant. Hence, the study recommends CO3cVO3c defective m-ZrO2 as the leading candidate to serve as a photoanode for PEC applications.
