Chitara Basant, Limbu Tej B, Orlando Jason D, Tang Yongan, Yan Fei
Department of Chemistry and Biochemistry, North Carolina Central University, Durham, NC 27707, USA.
Nanoscale. 2020 Aug 14;12(30):16285-16291. doi: 10.1039/d0nr02991b. Epub 2020 Jul 28.
Recently, a zipper two-dimensional (2D) material BiOSe belonging to the layered bismuth oxychalcogenide (BiOX: X = S, Se, Te) family, has emerged as an alternate candidate to van der Waals 2D materials for high-performance electronic and optoelectronic applications. This hints towards exploring the other members of the BiOX family for their true potential and bismuth oxysulfide (BiOS) could be the next member for such applications. Here, we demonstrate for the first time, the scalable room-temperature chemical synthesis and near-infrared (NIR) photodetection of ultrathin BiOS nanosheets. The thickness of the freestanding nanosheets was around 2-3 nm with a lateral dimension of ∼80-100 nm. A solution-processed NIR photodetector was fabricated from ultrathin BiOS nanosheets. The photodetector showed high performance, under 785 nm laser illumination, with a photoresponsivity of 4 A W, an external quantum efficiency of 630%, and a normalized photocurrent-to-dark-current ratio of 1.3 × 10 per watt with a fast response time of 100 ms. Taken together, the findings suggest that BiOS nanosheets could be a promising alternative 2D material for next-generation large-area flexible electronic and optoelectronic devices.
最近，属于层状硫族铋氧化物（BiOX：X = S、Se、Te）家族的二维（2D）材料BiOSe，已成为用于高性能电子和光电子应用的范德华二维材料的替代候选材料。这暗示着要探索BiOX家族的其他成员的真正潜力，而硫氧化铋（BiOS）可能是此类应用的下一个成员。在此，我们首次展示了超薄BiOS纳米片的可扩展室温化学合成及近红外（NIR）光探测性能。独立纳米片的厚度约为2 - 3纳米，横向尺寸约为80 - 100纳米。由超薄BiOS纳米片制备了一种溶液处理的近红外光探测器。该光探测器在785纳米激光照射下表现出高性能，光响应度为4 A/W，外量子效率为630%，归一化光电流与暗电流之比为每瓦1.3×10，响应时间快，为100毫秒。综上所述，这些发现表明BiOS纳米片可能是下一代大面积柔性电子和光电子器件的有前途的替代二维材料。
