(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長(zhǎng)沙 410083；
2. 中南大學(xué) 冶金科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 采用聚丙烯酰胺凝膠法制備納米BeO粉體，通過(guò)TG-DSC、XRD和SEM等測(cè)試手段研究凝膠前驅(qū)體的熱分解過(guò)程和所得粉體的性能，并借助負(fù)離子配位多面體生長(zhǎng)基元理論分析熱分解過(guò)程中納米BeO的結(jié)晶機(jī)理。結(jié)果表明：隨著溫度的升高，凝膠前驅(qū)體內(nèi)的有機(jī)凝膠逐漸分解，同時(shí)凝膠前驅(qū)體內(nèi)的硫酸鈹鹽脫除結(jié)晶水；當(dāng)溫度達(dá)到600 ℃左右時(shí)，有機(jī)凝膠完全分解，得到納米級(jí)的無(wú)水硫酸鈹；繼續(xù)升高溫度，納米級(jí)的無(wú)水硫酸鈹分解得到納米BeO；熱分解過(guò)程中，納米硫酸鈹通過(guò)生長(zhǎng)基元Be(SO4)6−斷鍵形成納米BeO，成核過(guò)程為受迫狀態(tài)下的非均勻成核。
關(guān)鍵字: 納米BeO；聚丙烯酰胺凝膠法；熱分解；結(jié)晶機(jī)理
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2.School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The BeO nanopowders were synthesized by the polyacrylamide gel method. The thermal decomposition process of precious gel and the properties of the obtained powder were investigated by TG-DSC, XRD and SEM, and the crystalline mechanism of nano-BeO in the thermal decomposition process was indicated by growth units model theory of anion coordination polyhedron. The results show that the organic gel in the precious gel is disintegrated gradually, and meanwhile the crystal water of the beryllium sulfate salt in precious gel is removed with the increase of temperature; when the temperature is about 600 ℃, the organic gel is disintegrated completely and nano-BeSO4 is obtained; BeO nanopowders are achieved under higher temperature. During the thermal decomposition of BeSO4 processes, the chemical bonds of its growth units Be(SO4)6− break down and nano-BeO forms, and the process of crystal nucleus formation is heterogeneous nucleation under the forced condition.
Key words: nano-BeO; polyacrylamide gel method; thermal decomposition; crystalline mechanism
