横向组分梯度二维合金W1-xBxS2(B=V,Nb)的制备及其器件性能研究

二维材料由于具有优异的光、电及力学等特性使其成为了近年来研究的热点。二维材料的性能调控是其在新型电子和光电子领域应用潜力的充分开发和实用化的关键。化学掺杂是调控二维材料性能最直接而有效的方法之一。相对单一均匀化学组分分布，具有化学组分梯度的二维合金在其性能调控、优化及功能协同方面具有独特的优势。本项目拟利用化学气相沉积的技术制备二维金属硫化物组分梯度合金W1-xBxS2(B=V,Nb)，研究宽化学组分范围的二维合金的制备技术和优化的工艺条件，测试分析梯度合金不同组分的结构、发光、磁等性能，阐明组分对其结构、光学性质、电、磁等特性等的调控和调控规律，结合理论计算，阐明其内在物理机制；构建基于组分梯度二维合金的器件，测试分析组分梯度对器件的光电、电磁输运等性质的影响，阐明影响载流子输运和光电探测性能的关键因素和机制，优化器件结构，提升器件光电探测性能。

The excellent optoelectronic and mechanical properties of two dimensional (2D) materials make it to be the hot-spot research in recent years. The modulation and control of properties of 2D materials plays a vital role in the development and practical application of the new generation of electronic and optoelectronic devices. Compared to the alloying with single and uniformly distributed dopant, 2D alloys with chemical composition gradient shows greater advantage in terms of the modulation and control, performance optimization, and function synergy. We propose here, using the chemical vapor deposition (CVD) technique, to fabricate the compositionally graded alloys of W1-xBxS2(B=V,Nb) with a wide range of chemical composition range, and uniformly and randomly distributed of alloyed element in the host materials. We are going to measure and analyse position (composition) dependent of various properties, such as of structural, optical, electrical, and magnetic, and try to illustrate the physical mechanism in combination with the theoretical calculations. We will build up device based on the compositionally graded alloys, characterize the optoelectronic, electric and magnetic transportation properties, illustrate the key factors and mechanism that the chemical gradient put on the carrier transportation and phtodetection performance, and accordingly, to improve the performance of photodetection by optimize the device structure.