Assembly of Phosphide Nanocrystals into Porous Networks: Formation of InP Gels and Aerogels
Assembly of Phosphide Nanocrystals into Porous Networks: Formation of InP Gels and Aerogels
复制标题
DOI：
10.1021/nn305959q
复制
发表时间：
2013-02-01
期刊：
影响因子：
17.1
通讯作者：
Brock, Stephanie L.
中科院分区：
文献类型：
--
作者：
Hitihami-Mudiyanselage, Asha;Senevirathne, Keerthi;Brock, Stephanie L.
溶胶-凝胶纳米粒子组装路线的适用性，以前采用的金属硫族化物，磷化物的情况下，磷化铟的报告。两种不同尺寸（3.5和6.0 nm）的InP纳米粒子的合成通过溶液相逮捕沉淀，与硫醇盐配体，并与H2 O2或O-2/光氧化诱导凝胶形成。将凝胶老化，溶剂交换，然后超临界干燥以获得具有中孔（2-50 nm）和大孔（>50 nm）的气凝胶，并且可及表面积类似于200 m2/g。相对于前体纳米颗粒，气凝胶显示出更高的带隙值，这表明在将纳米颗粒组装成3D架构的过程中，可能发生了粒度减小。与金属硫族化物凝胶化相反，InP凝胶没有使用四硝基甲烷（一种非氧转移氧化剂）形成。氧转移氧化剂的要求，结合X-射线光电子能谱数据显示氧化的磷，表明凝胶化是由于在界面处产生的磷含氧阴离子部分的缩合而发生的。将离散的InP纳米颗粒连接到3D多孔网络中同时保持量子限制的能力有望促进纳米结构InP在固态器件中的开发。
The applicability of sot-gel nanoparticle assembly routes, previously employed for metal chalcogenides, to phosphides is reported for the case of InP. Two different sizes (3.5 and 6.0 nm) of InP nanoparticles were synthesized by solution-phase arrested precipitation, capped with thiolate ligands, and oxidized with H2O2 or O-2/light to induce gel formation. The gels were aged, solvent-exchanged, and then supercritically dried to obtain aerogels with both meso- (2-50 nm) and macropores (>50 nm) and accessible surface areas of similar to 200 m(2)/g. Aerogels showed higher band gap values relative to precursor nanoparticles, suggesting that during the process of assembling nanoparticles into 3D architectures, particle size reduction may have taken place. In contrast to metal chalcogenide gelation, InP gels did not form using tetranitromethane, a non-oxygen-transferring oxidant. The requirement of an oxygen-transferring oxidant, combined with X-ray photoelectron spectroscopy data showing oxidized phosphorus, suggests gelation is occurring due to condensation of phosphorus oxoanionic moieties generated at the interfaces. The ability to link discrete InP nanoparticles Into a 3D porous network while maintaining quantum confinement is expected to facilitate exploitation of nanostructured InP in solid-state devices.