Bakry Mabrouk, Ismail Walid, Abdelfatah Mahmoud, El-Shaer Abdelhamid
Physics Department, Faculty of Science, Kafrelsheikh University, Kafrelsheikh, 33516, Egypt.
NanoScience and Technology Program, Faculty of Science, Kafrelsheikh University, Kafrelsheikh, 33516, Egypt.
Sci Rep. 2024 Oct 11;14(1):23788. doi: 10.1038/s41598-024-73352-5.
Zinc Oxide (ZnO) nanorods have great potential in several applications including gas sensors, light-emitting diodes, and solar cells because of their unique properties. Here, three low cost and ecofriendly techniques were used to produce ZnO nanorods on FTO substrates: hydrothermal, chemical bath deposition (CBD), and electrochemical deposition (ECD). This study explores the impact of such methods on the optical, structural, electrical, morphological, and photoelectrochemical properties of nanorods using various measurements. XRD analysis confirmed the hexagonal wurtzite structure of ZnO nanorods in all three methods, with hydrothermal showing a preferred orientation (002) and CBD and ECD samples showing multiple growth directions, with average particle sizes of 31 nm, 34 nm, and 33 nm, respectively. Raman spectra revealed hexagonal Wurtzite structure of ZnO, with hydrothermal method exhibiting higher E (high) peak at 438 cm than CBD and ECD methods. SEM results revealed hexagonal ZnO nanorods became more regular and thicker for the hydrothermal method, while CBD and ECD led to less uniform with voids. UV-vis spectra showed absorption lines between 390 nm and 360 nm. Optical bandgap energies were calculated as 3.32 eV, 3.22 eV, and 3.23 eV for hydrothermal, CBD, and ECD samples, respectively. PL spectra revealed UV emission band with a small intensity peak around 389 nm and visible emission peaks at 580 nm. Temperature dependent PL measurements for ZnO nanorods indicated that the intensities ratio between bound exciton and free exciton decreases with temperature increases for the three methods. Photocurrent measurements revealed ZnO nanorod films as n-type semiconductors, with photocurrent values of 2.25 µA, 0.28 µA, and 0.3 µA for hydrothermal, CBD, and ECD samples, and photosensitivity values of 8.01, 2.79, and 3.56 respectively. Our results suggest that the hydrothermal method is the most effective approach for fabricating high-quality ZnO nanorods for optoelectronic applications.
氧化锌（ZnO）纳米棒因其独特性能在包括气体传感器、发光二极管和太阳能电池在内的多种应用中具有巨大潜力。在此，采用了三种低成本且环保的技术在FTO衬底上制备ZnO纳米棒：水热法、化学浴沉积（CBD）法和电化学沉积（ECD）法。本研究通过各种测量方法探究了这些方法对纳米棒的光学、结构、电学、形态学和光电化学性质的影响。X射线衍射（XRD）分析证实，在所有三种方法中ZnO纳米棒均为六方纤锌矿结构，水热法显示出择优取向（002），而CBD法和ECD法的样品显示出多个生长方向，平均粒径分别为31纳米、34纳米和33纳米。拉曼光谱揭示了ZnO的六方纤锌矿结构，水热法在438厘米处的E（高）峰高于CBD法和ECD法。扫描电子显微镜（SEM）结果显示，水热法制备的六方ZnO纳米棒变得更加规则且更厚，而CBD法和ECD法导致的纳米棒不太均匀且有空隙。紫外-可见光谱显示在390纳米至360纳米之间有吸收线。水热法、CBD法和ECD法样品的光学带隙能量分别计算为3.32电子伏特、3.22电子伏特和3.23电子伏特。光致发光（PL）光谱揭示了紫外发射带，在389纳米左右有一个小强度峰，在580纳米处有可见发射峰。对ZnO纳米棒进行的温度相关PL测量表明，对于这三种方法，束缚激子与自由激子之间的强度比随温度升高而降低。光电流测量表明ZnO纳米棒薄膜为n型半导体，水热法、CBD法和ECD法样品的光电流值分别为2.25微安、0.28微安和0.3微安，光敏度值分别为8.01、2.79和3.56。我们的结果表明，水热法是用于光电子应用制备高质量ZnO纳米棒的最有效方法。
