Almomani Mohammad S, Ahmed Naser M, Rashid Marzaini, Ali M K M, Akhdar H, Aldaghri O, Ibnaouf K H
School of Physics, Universiti Sains Malaysia, Minden 11800, Penang, Malaysia.
Department of Physics, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia.
Nanomaterials (Basel). 2021 Nov 22;11(11):3158. doi: 10.3390/nano11113158.
Despite many dedicated efforts, the fabrication of high-quality ZnO-incorporated Zinc@Silicon (Zn@Si) core-shell quantum dots (ZnSiQDs) with customized properties remains challenging. In this study, we report a new record for the brightness enhancement of ZnSiQDs prepared via a unified top-down and bottom-up strategy. The top-down approach was used to produce ZnSiQDs with uniform sizes and shapes, followed by the bottom-up method for their re-growth. The influence of various NHOH contents (15 to 25 µL) on the morphology and optical characteristics of ZnSiQDs was investigated. The ZnSiQDs were obtained from the electrochemically etched porous Si (PSi) with Zn inclusion (ZnPSi), followed by the electropolishing and sonication in acetone. EFTEM micrographs of the samples prepared without and with NHOH revealed the existence of spherical ZnSiQDs with a mean diameter of 1.22 to 7.4 nm, respectively. The emission spectra of the ZnSiQDs (excited by 365 nm) exhibited bright blue, green, orange-yellow, and red luminescence, indicating the uniform morphology related to the strong quantum confinement ZnSiQDs. In addition, the absorption and emission of the ZnSiQDs prepared with NHOH were enhanced by 198.8% and 132.6%, respectively. The bandgap of the ZnSiQDs conditioned without and with NHOH was approximately 3.6 and 2.3 eV, respectively.
尽管付出了许多努力，但制备具有定制特性的高质量氧化锌掺杂锌@硅（Zn@Si）核壳量子点（ZnSiQDs）仍然具有挑战性。在本研究中，我们报告了通过统一的自上而下和自下而上策略制备的ZnSiQDs亮度增强的新记录。自上而下的方法用于制备尺寸和形状均匀的ZnSiQDs，然后采用自下而上的方法进行再生长。研究了不同NHOH含量（15至25μL）对ZnSiQDs形态和光学特性的影响。ZnSiQDs是通过电化学蚀刻含锌多孔硅（ZnPSi），然后在丙酮中进行电化学抛光和超声处理获得的。未添加和添加NHOH制备的样品的能量过滤透射电子显微镜（EFTEM）显微照片显示，分别存在平均直径为1.22至7.4nm的球形ZnSiQDs。ZnSiQDs（由365nm激发）的发射光谱呈现出亮蓝色、绿色、橙黄色和红色发光，表明与强量子限域ZnSiQDs相关的形态均匀。此外，添加NHOH制备的ZnSiQDs的吸收和发射分别增强了198.8%和132.6%。未添加和添加NHOH条件下的ZnSiQDs的带隙分别约为3.6和2.3eV。
