Nar Sibel, Stolz Arnaud, Machon Denis, Bourhis Eric, Andreazza Pascal, Boucherif Abderraouf, Semmar Nadjib
Groupe de Recherches sur l'Énergétique des Milieux Ionisés, GREMI, Université d'Orléans, CNRS, 14 Rue d'Issoudun, 45067 Orleans CEDEX 02, France.
Laboratoire Nanotechnologies et Nanosystèmes (LN2)-CNRS IRL-3463, Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, QC J1K OA5, Canada.
Nanomaterials (Basel). 2023 Apr 1;13(7):1254. doi: 10.3390/nano13071254.
Nanographene-mesoporous silicon (G-PSi) composites have recently emerged as a promising class of nanomaterials with tuneable physical properties. In this study, we investigated the impact of nanographene coating on the Seebeck coefficient of mesoporous silicon (PSi) obtained by varying two parameters: porosity and thickness. To achieve this, an electrochemical etching process on p + doped Si is presented for the control of the parameters (thicknesses varying from 20 to 160 µm, and a porosity close to 50%), and for nanographene incorporation through chemical vapor deposition. Raman and XPS spectroscopies confirmed the presence of nanographene on PSi. Using a homemade ZT meter, the Seebeck coefficient of the p + doped Si matrix was evaluated at close to 100 ± 15 µV/K and confirmed by UPS spectroscopy analysis. Our findings suggest that the Seebeck coefficient of the porous Si can be measured independently from that of the substrate by fitting measurements on samples with a different thickness of the porous layer. The value of the Seebeck coefficient for the porous Si is of the order of 750 ± 40 µV/K. Furthermore, the incorporation of nanographene induced a drastic decrease to approximately 120 ± 15 µV/K, a value similar to that of its silicon substrate.
纳米石墨烯-介孔硅（G-PSi）复合材料最近已成为一类具有可调物理性质的很有前景的纳米材料。在本研究中，我们通过改变孔隙率和厚度这两个参数，研究了纳米石墨烯涂层对介孔硅（PSi）塞贝克系数的影响。为此，提出了一种在p +掺杂硅上的电化学蚀刻工艺，用于控制参数（厚度从20到160μm不等，孔隙率接近50%），并通过化学气相沉积法掺入纳米石墨烯。拉曼光谱和XPS光谱证实了PSi上存在纳米石墨烯。使用自制的ZT测量仪，p +掺杂硅基体的塞贝克系数经评估接近100±15μV/K，并通过UPS光谱分析得到证实。我们的研究结果表明，通过对具有不同多孔层厚度的样品进行拟合测量，可以独立于衬底测量多孔硅的塞贝克系数。多孔硅的塞贝克系数值约为750±40μV/K。此外，纳米石墨烯的掺入使其急剧下降至约120±15μV/K，该值与其硅衬底的值相似。
