连续离子层吸附反应(SILAR)法制备AgGaS_2纳米薄膜及性能表征

Preparation and Properties of AgGaS_2 Nanofilms by Successive Ionic Layer Adsorption Reaction Method

采用连续离子层吸附反应(SILAR)法,通过500℃退火在玻璃衬底上制备出AgGaS2纳米薄膜。使用X射线衍射(XRD)、扫描电镜(SEM)、X射线能谱(EDS)、紫外可见(UV-Vis)谱和光致发光(PL)谱等对纳米薄膜的物相、形貌、化学配比和光学性能进行了定性和定量表征。XRD测试结果表明,实验获得产物为黄铜矿结构AgGaS2,并观测到(112)面和(224)面。使用Scherrer公式估算了AgGaS2产物的晶粒平均粒度大小约为30 nm。SEM观测到的AgGaS2纳米薄膜外形均匀一致,沉积紧密,薄膜沉积的纳米平均颗粒直径约为18～26 nm。EDS测试结果显示AgGaS2纳米薄膜中Ag、Ga和S三元素的原子相对百分含量为25.12%,26.66%和49.93%,其化学计量比几近于1:1:2物质的量比。通过紫外可见透过光谱得到截止波长为470.1 nm,禁带宽度为2.64 eV。室温PL测试发现发光中心在456 nm,与AgGaS2晶体发光中心相比产生了约40 nm的蓝移。以上结果充分表明SILAR法是一种制备AgGaS2纳米薄膜的有效方式。

AgGaS2 nanofilms have been prepared by the successive ionic layer absorption and reaction（SILAR） method on ITO glass substrate.The composition phase,microscopy,stoichiometric composition and optical properties of AgGaS2 nanofilm were characterized by X-ray diffraction（XRD）,scan electron microscopy（SEM）,energy dispersive spectrometer（EDS）,UV-Vis spectrum and photo-luminescence（PL）.It was proved by XRD that AgGaS2 with chalcopyrite crystal structure was obtained.It＇s shown that the AgGaS2 nanofilms are（112） oriented preferentially upon substrate.The size of these crystals was about 30 nm which was calculated by Scherrer formula.It was showed in SEM image that the AgGaS2 nanofilms were highly uniform and the sizes were about 18-26 nm.The relative contents of Ag,Ga and S were 25.12%,26.66% and 49.93% respectively which means the stoichiometry of AgGaS2 nanofilm was about 1∶1∶2.It can be derived from the UV-Vis spectrum that the limiting wavelength was 470.1 nm and the band gap energy was estimated to be about 2.64 eV.At room temperature,the luminescence property was investigated with PL spectrum.The emission center was at 456 nm.It was blue-shifted about 40 nm compared with the value of single crystal AgGaS2.Based on all results mentioned above,it can be concluded that SILAR method is preferable to synthesize AgGaS2 nanofilm.