不同气氛下SiO_x纳米线的制备及形貌、红外、光致发光研究

Preparation of SiO_x nanowires in different atmosphere,their morphology,PL and FTIR properties

以N2/H2、N2或NH3为载气,利用碳辅助化学气相沉积法,常压1140℃下在石英衬底上制备了大量直径为20—300nm,长数百微米的非晶SiOx纳米线.制备得到的纳米线具有高度定向生长的特性.利用透射电子显微镜、扫描电子显微镜及电子能谱对SiOx纳米线的形貌及组分进行了分析,Si与O原子之比为1∶1.8.傅里叶红外吸收谱显示了非晶氧化硅的三个特征峰(482,806和1095cm-1)及1132cm-1无序氧化硅结构的强吸收峰.SiOx纳米线光致发光光谱(PL)在440nm(2.83eV)处具有较强的荧光峰;N2为载气生长的SiOx纳米线的PL峰强比NH3为载气生长的SiOx纳米线峰强大四个数量级.

High-density SiOx nanowires were fabricated on a large-scale using carbon-assisted CVD method by Fe—Al—O catalyst at 1140℃ in flowing N2/H2,N2 and NH3 atmospheres.The SiOx nanowires have uniform diameters of 20—300nm and lengths of up to a few hundred micrometers.SEM,TEM,EDS,FTIR and PL were preformed to characterize the microstructure,composition and optical performance of the nanowires.Energy dispersive X-ray spectral analysis reveals that the nanowires consist of Si and O elements in an atomic ratio of approximately 1：1.8.The nanowires show IR absorption peaks at 482,806,1095 and 1132cm^-1.The PL peak of the nanowires is located at 440nm（2.83eV）.The PL inensity of the SiOx nanowire（N2）is 104 times that of the SiOx nanowire（N2/NH3）.