A Facile and Green Approach for the Controlled Synthesis of Porous SnO2 Nanospheres: Application as an Efficient Photocatalyst and an Excellent Gas Sensing Material
A Facile and Green Approach for the Controlled Synthesis of Porous SnO2 Nanospheres: Application as an Efficient Photocatalyst and an Excellent Gas Sensing Material
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DOI：
10.1021/am301840s
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发表时间：
2012-11-01
影响因子：
9.5
通讯作者：
Manorama, Sunkara V.
中科院分区：
文献类型：
--
作者：
Boppella, P. Manjula Ramireddy;Manorama, Sunkara V.
本文介绍了一种利用绿色化学原理合成多孔二氧化锡纳米球的简便方法。SnO 2纳米粒子的低温（类似于50摄氏度）合成及其自组装成有组织的、均匀的、单分散的、具有高表面积的多孔纳米球是通过控制葡萄糖的浓度来促进的，葡萄糖充当稳定剂和结构导向剂。对锡酸盐与葡萄糖摩尔浓度比的系统控制决定了获得单分散纳米球的确切条件，优先于随机聚集。结构、形貌和化学组成的详细表征表明，合成的材料，50 nm的SnO 2多孔纳米球具有约160 m2/g的BET表面积。每个多孔纳米球由数百个直径约2-3 nm的具有四氢叶酸钙晶体结构的纳米颗粒组成。SnO 2纳米球对橙子具有较高的光催化活性，并且具有良好的可回收性。由于这种光催化剂的高活性和稳定性，该材料是环境修复应用的理想材料。此外，SnO 2纳米球显示出优异的对氢气的气敏性能。用Pd对纳米球进行表面改性，将这种传感材料转变为高灵敏度和选择性的室温氢传感器。
A facile and elegant methodology invoking the principles of Green Chemistry for the synthesis of porous tin dioxide nanospheres has been described. The low-temperature (similar to 50 degrees C) synthesis of SnO2 nanoparticles and their self-assembly into organized, uniform, and monodispersed porous nanospheres with high surface area is facilitated by controlling the concentration of glucose, which acts as a stabilizing as well as structure-directing agent. A systematic control on the stannate to glucose molar concentration ratio determines the exact conditions to obtain monodispersed nanospheres, preferentially over random aggregation. Detailed characterization of the structure, morphology, and chemical composition reveals that the synthesized material, 50 nm SnO2 porous nanospheres possess BET surface area of about 160 m(2)/g. Each porous nanosphere consists of a few hundred nanoparticles similar to 2-3 nm in diameter with tetragonal cassiterite crystal structure. The SnO2 nanospheres exhibit elevated photocatalytic activity toward methyl orange with good recyclability. Because of the high activity and stability of this photocatalyst, the material is ideal for applications in environmental remediation. Moreover, SnO2 nanospheres display excellent gas sensing capabilities toward hydrogen. Surface modification of the nanospheres with Pd transforms this sensing material into a highly sensitive and selective room-temperature hydrogen sensor.