Materials Science and Technology Division, CSIR-North East Institute of Science and Technology, Jorhat-785006, Assam, India.
Academy of Scientific and Innovative Research, CSIR-HRDC, Ghazaiabad, UP, India.
Phys Chem Chem Phys. 2022 Dec 14;24(48):29781-29790. doi: 10.1039/d2cp04198g.
Surface modification of mesoporous SBA-15 with (3-mercaptopropyl) trimethoxysilane greatly enhances its capability to adsorb the tetrachloroauric anion (AuCl). The calcination of the sample after the adsorption experiment led to the generation of homogeneously dispersed, spherical, single crystalline gold nanoparticles (Au NPs) of less than 5 nm size, embedded on SBA-15 as observed from the TEM images. The as-prepared SBA-15/Au nanohybrid material has offered excellent catalytic activity for the selective oxidation of cyclohexane using TBHP as the oxidant in the absence of any solvent. A maximum of 48.7% cyclohexane conversion was achieved and surprisingly, cyclohexanone (K) has much higher selectivity (>95%) than cyclohexanol (A). The hot-filtration study confirmed the leach-resistant characteristics as well as the true heterogeneous catalytic activity of the SBA-15/Au nanohybrid catalyst. The catalyst was recycled up to four times without significant loss in its catalytic activity.
介孔 SBA-15 用（3-巯丙基）三甲氧基硅烷进行表面改性，极大地提高了其吸附四氯金酸根阴离子（AuCl）的能力。吸附实验后对样品进行煅烧，导致在 SBA-15 上生成了均匀分散、尺寸小于 5nm 的球形单晶金纳米粒子（Au NPs），从 TEM 图像中可以观察到。所制备的 SBA-15/Au 纳米杂化材料在无溶剂存在的情况下，以 TBHP 为氧化剂，对环己烷的选择性氧化表现出优异的催化活性。环己烷的转化率最高可达 48.7%，令人惊讶的是，环己酮（K）的选择性（>95%）远高于环己醇（A）。热过滤研究证实了 SBA-15/Au 纳米杂化催化剂具有抗浸出特性和真正的多相催化活性。该催化剂在不损失其催化活性的情况下可重复使用四次。
