Rauf Abdur, Adil Muhammad, Mian Shabeer Ahmad, Rahman Gul, Ahmed Ejaz, Mohy Ud Din Zia, Qun Wei
Department of Physics, University of Peshawar, Peshawar, 25120, Pakistan.
Department of Physics, Islamia College University, Peshawar, 25120, Pakistan.
Sci Rep. 2021 Jan 8;11(1):41. doi: 10.1038/s41598-020-78824-y.
Hematite (FeO) is one of the best candidates for photoelectrochemical water splitting due to its abundance and suitable bandgap. However, its efficiency is mostly impeded due to the intrinsically low conductivity and poor light absorption. In this study, we targeted this intrinsic behavior to investigate the thermodynamic stability, photoconductivity and optical properties of rhodium doped hematite using density functional theory. The calculated formation energy of pristine and rhodium doped hematite was - 4.47 eV and - 5.34 eV respectively, suggesting that the doped material is thermodynamically more stable. The DFT results established that the bandgap of doped hematite narrowed down to the lower edge (1.61 eV) in the visible region which enhanced the optical absorption and photoconductivity of the material. Moreover, doped hematite has the ability to absorb a broad spectrum (250-800) nm. The enhanced optical absorption boosted the photocurrent and incident photon to current efficiency. The calculated results also showed that the incorporation of rhodium in hematite induced a redshift in optical properties.
赤铁矿（FeO）因其储量丰富且带隙合适，是光电化学水分解的最佳候选材料之一。然而，由于其固有低电导率和光吸收差，其效率大多受到阻碍。在本研究中，我们针对这种固有行为，使用密度泛函理论研究了铑掺杂赤铁矿的热力学稳定性、光电导率和光学性质。计算得出的原始赤铁矿和铑掺杂赤铁矿的形成能分别为-4.47 eV和-5.34 eV，这表明掺杂材料在热力学上更稳定。密度泛函理论结果表明，掺杂赤铁矿的带隙在可见光区域缩小到了下边缘（1.61 eV），这增强了材料的光吸收和光电导率。此外，掺杂赤铁矿能够吸收宽光谱（250 - 800）nm。增强的光吸收提高了光电流和入射光子到电流的效率。计算结果还表明，在赤铁矿中掺入铑会导致光学性质发生红移。
