In this study, the effects of different precursor concentrations on the growth and characteristics properties of the zinc oxide (ZnO) nanorods (NRs) synthesized by using modified and conventional chemical bath deposition (CBD) methods were investigated. The morphologic, structural and optical properties of synthesized ZnO NRs with different precursor concentrations were studied using various characterization techniques. The experimental results show that the varying precursor concentration of the reactants has a remarkable and significant effect on the growth and characteristics properties of ZnO NRs. In addition, the characteristic properties of ZnO NRs grown using the modified method showed significantly improved and enhanced properties. The average length of grown ZnO NRs increased with increased precursor concentration; it can be seen that longer ZnO NRs have been investigated using the modified CBD methods. The ZnO NRs synthesized at 0.05 M using the modified method were grown with high aspect ratios than the ZnO NRs grown using conventional means which were 25 and 11, respectively. The growth rate increased with increased precursor concentration; it can be observed that a higher growth rate was seen using the modification CBD method. Furthermore, XRD results for the two cases reveal that the grown ZnO samples were a nanorod-like in shape and possessed a hexagonal wurtzite structure with high crystal quality. No other phases from the impurity were observed. The diffraction peaks along (002) plane became higher, sharper and narrower as precursor concentration increased, suggesting that the crystalline quality of ZnO NRs grown using the modified method was more enhanced and better than conventional methods. However, optical studies show that the transmittance at each concentration was more than two times higher than the transmittance using the modified CBD method. In addition, optical studies demonstrated that the ZnO NRs grown by using modified and conventional methods had a direct E_g in the range of (3.2–3.26) eV and (3.15–3.19) eV, respectively. It was demonstrated in two methods that ZnO NRs grown at a precursor concentration 0.05 M gave the most favorable result, since the NRs had best characteristic properties.

中文翻译：

---

改进的化学浴沉积方法增强ZnO纳米棒的性能：前体浓度的影响

在这项研究中，研究了不同的前体浓度对使用改良和常规化学浴沉积（CBD）方法合成的氧化锌（ZnO）纳米棒（NRs）的生长和特性的影响。使用各种表征技术研究了具有不同前体浓度的合成ZnO NR的形态，结构和光学性质。实验结果表明，变化的反应物前体浓度对ZnO NRs的生长和特性具有显着而显着的影响。此外，使用改良方法生长的ZnO NRs的特性表现出明显的改善和增强。生长的ZnO NRs的平均长度随前体浓度的增加而增加；可以看出，使用改进的CBD方法研究了更长的ZnO NR。与使用常规方法生长的ZnO NRs分别为25和11相比，使用改良方法以0.05 M合成的ZnO NRs以高的长宽比生长。生长速度随着前驱物浓度的增加而增加；可以看出，使用改进的CBD方法可以看到更高的生长速度。此外，这两种情况的XRD结果表明，生长的ZnO样品呈纳米棒状，并具有六方纤锌矿结构，具有较高的晶体质量。没有观察到来自杂质的其他相。随着前驱物浓度的增加，沿（002）平面的衍射峰变高，变窄。这表明使用改良方法生长的ZnO NRs的晶体质量比常规方法更好，更好。但是，光学研究表明，每种浓度下的透射率比使用改进的CBD方法的透射率高两倍以上。此外，光学研究表明，使用改良和常规方法生长的ZnO NR具有直接E_g分别在（3.2–3.26）eV和（3.15–3.19）eV的范围内。用两种方法证明，在前体浓度为0.05 M的条件下生长的ZnO NRs表现出最佳的效果，因为NRs具有最佳的特性。