納米鈷氧化物與碳復合材料的制備及其對AP熱分解的催化性能研究
發(fā)布時間:2018-07-01 14:14
本文選題:α-Co(OH)_2 + Co3O4; 參考:《西南科技大學》2017年碩士論文
【摘要】:鈷氧化合物因為其獨特的結構和性能而引起人們對其進行了廣泛的研究。α-Co(OH)_2由于具有較大的比表面積和良好的氧化還原特性且資源相對豐富、價格相對低廉而引起了人們的廣泛關注。但是在現有的多數制備納米級α-Co(OH)_2的方法中,普遍存在操作復雜、條件苛刻、結構不易控制等問題。四氧化三鈷(Co_3O_4)擁有良好的空電子軌道,容易接受電子對而生成穩(wěn)定的反應中間產物,促使反應快速地向正反應方向進行,所以Co_3O_4可以作為一種優(yōu)良的催化劑材料。但是對于能夠兼顧工藝簡單、產量高、能耗相對較小以及形貌均一可控的四氧化三鈷制備方法依然有待探索。針對以上問題,本文采用簡單的鈷鹽與堿溶液混合的方法制備出納米級別的球形花狀α-Co(OH)_2;以花狀α-Co(OH)_2、細菌纖維素碳(CBC)以及氧化石墨烯(GO)為原料分別制備出Co_3O_4/CBC和Co_3O_4/GO納米復合材料并研究了復合材料對高氯酸銨的催化性能,主要內容如下:(1)以六水氯化鈷和氫氧化鈉以及氨水為原料,在室溫下制備了兩種結構和性能優(yōu)異的α-Co(OH)_2顆粒:微米花狀α-Co(OH)_2和納米級花狀α-Co(OH)_2,這兩種α-Co(OH)_2對AP的熱分解表現出了良好的催化作用,當催化劑的添加量為3%時,使得AP的低溫熱分解過程消失,高溫熱分解峰分別提前到了264和285℃,較純AP的高溫熱分解峰分別提前了175和158℃。(2)以花狀α-Co(OH)_2為原料,通過水浴法制備了直徑約10nm的納米顆粒,并分別利用CBC和GO為基底,制備出了Co_3O_4/CBC和Co_3O_4/GO兩種納米復合材料。Co_3O_4、Co_3O_4/CBC和Co_3O_4/GO均對AP具有良好的催化性能,并研究了不同Co_3O_4:C對AP熱分解性能的影響。得出結論:當CBC和GO的添加量為14%,Co_3O_4/CBC和Co_3O_4/GO復合材料的催化性能最佳。當催化劑的添加量為3%時,使得AP的低溫熱分解過程消失,高溫熱分解峰分別提前到了289和272℃,較純AP的高溫熱分解峰分別提前了150和167℃
[Abstract]:Cobalt oxide compounds have been widely studied because of their unique structure and properties. 偽 -Co (OH) _ 2 has relatively abundant resources because of its large specific surface area and good redox properties. The relatively low price has aroused widespread concern. However, in most of the existing methods of preparing nanocrystalline 偽 -Co (OH) _ 2, there are many problems such as complex operation, harsh conditions and difficult control of the structure of 偽 -Co (OH) _ 2. Cos _ 3O _ (4) has a good empty electron orbit, and it is easy to accept electron pairs to form a stable reaction intermediate product, which promotes the reaction to proceed rapidly in the direction of positive reaction, so CoStack3O _ 4 can be used as a good catalyst material. However, the preparation method of cobalt trioxide, which has the advantages of simple process, high yield, relatively low energy consumption and uniform morphology, remains to be explored. In view of the above problems, In this paper, a simple method of mixing cobalt salt with alkali solution was used to prepare nano-sized spherical flower-like 偽 -Co (OH) 2s; using flower-like 偽 -Co (OH) 2, bacterial cellulose carbon (CBC) and graphene oxide (go) as raw materials, Co3O4 / CBC and Co3O4go nanocomposites were prepared and studied. The catalytic properties of the composite for ammonium perchlorate, The main contents are as follows: (1) using cobalt chloride hexahydrate, sodium hydroxide and ammonia water as raw materials, Two 偽 -Co (OH) _ 2 particles with excellent structure and performance were prepared at room temperature: micron-floral 偽 -Co (OH) _ 2 and nanoscale 偽 -Co (OH) _ 2. These two 偽 -Co (OH) _ 2 exhibited a good catalytic effect on the thermal decomposition of AP. The low temperature thermal decomposition process of AP disappeared, and the peak of high temperature thermal decomposition was advanced to 264 鈩,
本文編號:2088045
本文鏈接:http://sikaile.net/kejilunwen/cailiaohuaxuelunwen/2088045.html
最近更新
教材專著