近年來中空材料因其廣泛的應用於各個領域中，所以受到越來越多的關注，常用於催化劑、保護劑及藥物載體等。而銀的應用範圍也很廣，常用於催化劑、導體、電子元件及創傷敷料。前人的研究中，以有許多製備銀顆粒的方法，譬如沉澱法和水熱法，而中空銀顆粒也有許多的製備方法，譬如溶膠凝膠法及科肯達效應，但未有以噴霧熱解法做中空銀顆粒的研究，而噴霧熱解法是較為低成本且可量產的製程。本研究以硝酸銀和醋酸銀為前驅物，並添加甘胺酸及澱粉，利用噴霧熱解法製備，使銀顆粒產生中空形貌，以熱重/熱差分析儀量測前驅物及添加物之熱裂解溫度，並以掃描式電子顯微鏡及穿透式電子顯微鏡觀察製備出的中空銀顆粒的形貌與大小，用X光繞射儀與選區電子繞射鑑定其結晶結構，本研究結果顯示前驅物添加甘胺酸及澱粉可得到中空或核殼狀的銀顆粒。透過不同的添加物以及添加物濃度的控制，可控制銀顆粒的孔隙度。最後本研究將中空銀顆粒作紫外線-可見光/近紅外線分析儀以及比表面積量測，發現中空銀顆粒相較實心顆粒對於可見光的吸收較少，且比表面積較高。

Recently hollow materials have received much attention due to their wide applications in catalysts, protective agent and drug carriers Silver also has wide applications in catalysts, conductors, electronic components and wound dressings. The method of precipitation and hydrothermal synthesis and the techniques of sol-gel and Kirkendall effect method have been used to fabricate silver and hollow silver particles. However, there is no research about producing hollow silver particles by spray pyrolysis(SP) process. SP process has advantages of low cost and feasibility for mass production. Here we prepared silver particles from the precursors silver nitrate and silver acetate, and added in glycine and starch using the SP process. The decomposed temperature of precursor was measured using thermogravimetric/differential thermal analysis (TG-DTA). Also, the morphology and size of the synthesized silver particles were characterized by scanning electron microscope (SEM) and transmission electron microscopy (TEM). Respectively, X-ray diffractometer (XRD) and selected area electron diffraction (SAED) were used to investigate the crystalline structure. The results show that the precursors add to glycine and starch could receive the hollow or core-shell silver particles. We control porosity of silver particles by different additives and concentration of additives. Finally, we performed UV-Vis/NIR spectrometers and BET, and the result suggest that hollow silver particles absorb less visible light and higher specific surface area than the that of solid silver particles.

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