Shin Seung Wook, Oh Hyun Pil, Pawar S M, Moon Jong-Ha, Kim Jin Hyeok
Department of Materials Science and Engineering, Chonnam National University, Gwangju 500-757, Korea.
J Nanosci Nanotechnol. 2010 May;10(5):3686-90. doi: 10.1166/jnn.2010.2330.
The nanocrystalline Zinc Sulfide (ZnS) thin films were prepared on glass substrates by chemical bath deposition (CBD) method using aqueous solutions of zinc acetate, thiourea and tri-sodium citrate in alkaline medium at 80 degrees C. The tri-sodium citrate acts as a complexing agent. The effects of complexing agent and annealing atmosphere (95%N2 + 5%H2S) on structural, morphological and optical properties of ZnS thin films were studied using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and optical absorption. XRD study revealed that single phase ZnS powder was formed in the solution with tri-sodium citrate, however, ZnS and ZnO mixed phase powder was formed in the solution without tri-sodium citrate. The films deposited with trisodium citrate showed ZnS with hexagonal wurtzite phase. However, annealed film in (N2 + H2S) atmosphere showed cubic (zincblende) phase. FE-SEM images show that grain size of as-deposited and annealed ZnS films are about 20 nm and 50 nm, respectively. Optical absorption study showed that the films have moderate optical transmission from 65% to 75% in the visible region and the optical band gap energy of as-deposited ZnS film is 3.91 eV and it decreases to 3.73 eV after annealing.
采用化学浴沉积（CBD）法，以醋酸锌、硫脲和柠檬酸三钠的水溶液为原料，在碱性介质中于80℃在玻璃基板上制备了纳米晶硫化锌（ZnS）薄膜。柠檬酸三钠作为络合剂。利用X射线衍射（XRD）、场发射扫描电子显微镜（FE-SEM）和光吸收研究了络合剂和退火气氛（95%N2 + 5%H2S）对ZnS薄膜结构、形貌和光学性能的影响。XRD研究表明，在含有柠檬酸三钠的溶液中形成了单相ZnS粉末，然而，在不含柠檬酸三钠的溶液中形成了ZnS和ZnO混合相粉末。用柠檬酸三钠沉积的薄膜显示出具有六方纤锌矿相的ZnS。然而，在（N2 + H2S）气氛中退火的薄膜显示出立方（闪锌矿）相。FE-SEM图像表明，沉积态和退火态ZnS薄膜的晶粒尺寸分别约为20nm和50nm。光吸收研究表明，薄膜在可见光区域具有65%至75%的适度光透射率，沉积态ZnS薄膜的光学带隙能量为3.91eV，退火后降至3.73eV。
