Benzo[ghi]perylene monoimide based photosensitive lamellar Cd-doped ZnO nanohybrids
作者:Shruti Verma、Manoj K. Manna、Sushil K. Pandey、Apurba K. Das、Shaibal Mukherjee
DOI:10.1039/c4ra13712d
日期:——
Lamellar hybrid inorganic/organic nanostructures comprising of alternating layers of benzo[ghi]perylene monoimide and Cd-doped ZnO called BPyM/CZO nanohybrids have been synthesized electrochemically on Ga-doped ZnO/Si. In order to study the effect of organic surfactant, inorganic CZO nanorods have also been electrochemically synthesized. The role of annealing and organic surfactant on morphology, structure, composition and opto-electronic properties is analyzed. The nanohybrids and nanorods are c-axis oriented preferentially with their (002) direction perpendicular to the substrate surface. Annealed BPyM/CZO nanohybrids show visible orange photoluminescence emission while unannealed nanohybrids and inorganic CZO nanorods emit white emission at room temperature. The annealed nanohybrids and inorganic nanorods tend to follow the Varshni equation with temperature variation from 80 K to 300 K. Spectroscopic ellipsometry reveals the thickness, refractive index and band gap of the nanostructures. Annealing tends to expand the band gap by 50 meV in the case of inorganic CZO nanorods, but shrinks the band gap by 20 meV for BPyM/CZO nanohybrids. Temperature dependent photosensitivity measurements reveal that BPyM/CZO nanohybrids are highly photosensitive, ∼8 fold and ∼4 fold higher than inorganic CZO nanorods at 80 K and 300 K, respectively. The studies indicate that BPyM/CZO nanohybrids hold potential as photosensors.
在掺镓 ZnO/Si 上电化学合成了由交替层状的苯并[ghi]苝单亚胺和掺镉 ZnO 组成的片状无机/有机杂化纳米结构,称为 BPyM/CZO 纳米杂化物。为了研究有机表面活性剂的影响,还电化学合成了无机 CZO 纳米棒。分析了退火和有机表面活性剂对形貌、结构、组成和光电特性的作用。纳米杂化物和纳米棒优先采用 c 轴取向,其 (002) 方向垂直于衬底表面。退火后的 BPyM/CZO 纳米杂化物发出可见的橙色光致发光,而未退火的纳米杂化物和无机 CZO 纳米棒则在室温下发出白色光。光谱椭偏仪显示了纳米结构的厚度、折射率和带隙。无机 CZO 纳米棒的退火会使带隙扩大 50 meV,而 BPyM/CZO 纳米杂化的退火会使带隙缩小 20 meV。与温度相关的光敏性测量结果表明,BPyM/CZO 纳米杂化具有很高的光敏性,在 80 K 和 300 K 时分别比无机 CZO 纳米棒高出 8 倍和∼4 倍。研究表明,BPyM/CZO 纳米杂化物具有作为光传感器的潜力。