Naffeti Mariem, Zaïbi Mohamed Ali, García-Arias Alejandro Vidal, Chtourou Radhouane, Postigo Pablo Aitor
Laboratory of Nanomaterials and Systems for Renewable Energies (LaNSER), Research and Technology Center of Energy, Techno-Park Borj-Cedria, Tunis 2050, Tunisia.
Instituto de Micro y Nanotecnología, IMN-CNM, CSIC (CEI UAM+CSIC), Isaac Newton, 8, 28760 Madrid, Spain.
Nanomaterials (Basel). 2022 Oct 24;12(21):3729. doi: 10.3390/nano12213729.
In this paper, we report a novel design of bismuth nanoparticle-passivated silicon nanowire (Bi@SiNW) heterojunction composites for high diode performances and improved effective carrier lifetime and absorption properties. High-density vertically aligned SiNWs were fabricated using a simple and cost-effective silver-assisted chemical etching method. Bi nanoparticles (BiNPs) were then anchored in these nanowires by a straightforward thermal evaporation technique. The systematic study of the morphology, elemental composition, structure, and crystallinity provided evidence for the synergistic effect between SiNWs and BiNPs. Bi@SiNWs exhibited an eight-fold enhancement of the first-order Raman scattering compared to bare silicon. Current-voltage characteristics highlighted that bismuth treatment dramatically improved the rectifying behavior and diode parameters for Bi-passivated devices over Bi-free devices. Significantly, Bi wire-filling effectively increased the minority carrier lifetime and consequently reduced the surface recombination velocity, further indicating the benign role of Bi as a surface passivation coating. Furthermore, the near-perfect absorption property of up to 97% was achieved. The findings showed that a judicious amount of Bi coating is required. In this study the reasons behind the superior improvement in Bi@SiNW's overall properties were elucidated thoroughly. Thus, Bi@SiNW heterojunction nanocomposites could be introduced as a promising and versatile candidate for nanoelectronics, photovoltaics and optoelectronics.
在本文中，我们报道了一种新型的铋纳米颗粒钝化硅纳米线（Bi@SiNW）异质结复合材料的设计，该材料具有高二极管性能、更长的有效载流子寿命和更好的吸收特性。采用简单且经济高效的银辅助化学蚀刻方法制备了高密度垂直排列的硅纳米线。然后通过直接热蒸发技术将铋纳米颗粒（BiNPs）锚定在这些纳米线中。对其形貌、元素组成、结构和结晶度的系统研究为硅纳米线和铋纳米颗粒之间的协同效应提供了证据。与裸硅相比，Bi@SiNW的一阶拉曼散射增强了八倍。电流-电压特性表明，铋处理显著改善了铋钝化器件相对于无铋器件的整流行为和二极管参数。值得注意的是，铋线填充有效地提高了少数载流子寿命，从而降低了表面复合速度，进一步表明了铋作为表面钝化涂层的良性作用。此外，还实现了高达97%的近乎完美的吸收特性。研究结果表明，需要适量的铋涂层。在本研究中，对Bi@SiNW整体性能卓越提升背后的原因进行了深入阐释。因此，Bi@SiNW异质结纳米复合材料有望成为纳米电子学、光伏和光电子学领域中一种有前途且用途广泛的候选材料。
