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采用共焦显微Ｒａｍａｎ光谱和Ｘ－射线衍射方法表征了负载型ＰｄＣｌ２／ＳｉＯ２和Ｐｄ－Ｂ／ＳｉＯ２非晶态合金催化剂的结构。结果表明ＰｄＣｌ２分散在ＳｉＯ２载体上后，与载体表面的相互作用使其在室温时即发生β→α构型转变。Ｐｄ－Ｂ／ＳｉＯ２非晶态合金的Ｒａｍａｎ光谱在３００－５００ｃｍ－１区域内呈现一大的弥散峰。与无负载Ｐｄ－Ｂ非晶态合金比较初步认定该弥散峰与Ｐｄ－Ｂ键振动有关，温度升高Ｐｄ－Ｂ／ＳｉＯ２催化活性下降，其主要原因为Ｐｄ－Ｂ／ＳｉＯ２非晶态合金在高温下逐渐晶化为Ｐｄ金属所致。ＰｄＣｌ２与ＳｉＯ２载体表面的相互作用使其具有较高的分散性，由此还原制备的Ｐｄ－Ｂ／ＳｉＯ２非晶态合金较之无负载Ｐｄ－Ｂ非晶态合金更加微细化，因而具有更大的活性比表面
The structures of supported PdCl2 / SiO2 and Pd-B / SiO2 amorphous alloy catalysts were characterized by confocal microscopy Raman spectroscopy and X-ray diffraction. The results show that PdCl2 dispersed on the SiO2 carrier, the interaction with the carrier surface so that it occurs at room temperature when the β → α configuration transition. The Raman spectrum of Pd-B / SiO2 amorphous alloy shows a large dispersion peak in the region of 300-500 cm-1. Compared with the unloaded Pd-B amorphous alloy, the dispersion peak was preliminarily determined to be related to the vibration of the Pd-B bond. The catalytic activity of Pd-B / SiO2 decreased with the increase of temperature. The main reason was that Pd-B / Gradually crystallized into Pd metal due to high temperature. The interaction between PdCl2 and SiO2 carrier surface makes it more dispersive, and the Pd-B / SiO2 amorphous alloy prepared by reduction is more refined than the unloaded Pd-B amorphous alloy and thus has a larger The activity of the surface