论文标题
通过替代NB掺杂来调节单层过渡金属二核苷的电子结构
Modulating Electronic Structure of Monolayer Transition Metal Dichalcogenides by Substitutional Nb-Doping
论文作者
论文摘要
调节单层过渡金属二核苷（TMDC）的电子结构对许多应用很重要，并且掺杂是实现此目标的有效方法，但控制挑战。在这里，我们报告了在化学蒸气沉积过程中尼伯（NB）的原位替代掺杂在具有可调浓度的TMDC中。以单层WS2为例，将NB掺入其晶格会导致带隙在1.98 eV范围内变化至1.65 eV。值得注意的，电运输测量和密度功能理论计算表明，NB掺杂剂的4D电子轨道在费米水平附近有助于NB掺杂的WS2状态的密度，从而导致N至P-Type转换。 NB掺杂还降低了WS2中氢吸收的能层，从而改善了电催化氢的演化性能。这些结果突出了受控掺杂在调节TMDC的电子结构及其在电子相关应用中的使用方面的有效性。
Modulating electronic structure of monolayer transition metal dichalcogenides (TMDCs) is important for many applications and doping is an effective way towards this goal, yet is challenging to control. Here we report the in-situ substitutional doping of niobium (Nb) into TMDCs with tunable concentrations during chemical vapour deposition. Taking monolayer WS2 as an example, doping Nb into its lattice leads to bandgap changes in the range 1.98 eV to 1.65 eV. Noteworthy, electrical transport measurements and density functional theory calculations show that the 4d electron orbitals of the Nb dopants contribute to the density of states of Nb-doped WS2 around the Fermi level, resulting in an n to p-type conversion. Nb-doping also reduces the energy barrier of hydrogen absorption in WS2, leading to an improved electrocatalytic hydrogen evolution performance. These results highlight the effectiveness of controlled doping in modulating the electronic structure of TMDCs and their use in electronic related applications.
