本文選題：少層h-BN　切入點(diǎn)：球磨　出處：《江蘇大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：h-BN納米材料作為近年來發(fā)現(xiàn)的新型二維納米材料,具有很多優(yōu)異的物理特性和化學(xué)性能,使其在治理環(huán)境水質(zhì)污染方面、可再生能源工業(yè)化方面、新型微納米電子器件方面都具有很大的應(yīng)用前景。目前,高質(zhì)量和可工業(yè)放大生產(chǎn)的層狀h-BN的制備成為氮化硼商業(yè)化應(yīng)用的限制因素。本文以商業(yè)化h-BN粉末為前驅(qū)體,采用次氯酸鈉水溶液輔助球磨剝離方法開發(fā)出低成本、高產(chǎn)量的少層h-BN。這種方法可以獲得少層(2-4層)h-BN,并且h-BN層狀面內(nèi)結(jié)構(gòu)損壞小,產(chǎn)品的產(chǎn)率高達(dá)21%。以少層h-BN為載體,Ag納米顆粒為催化劑,在NaBH4存在條件下有效地催化還原對(duì)硝基苯酚轉(zhuǎn)化為對(duì)氨基苯酚,得到的一級(jí)反應(yīng)速率常數(shù)為7.13×10-3s-1,大于商品h-BN負(fù)載Ag納米粒子的一級(jí)反應(yīng)速率常數(shù),并且催化劑具有較好的穩(wěn)定性,可以循環(huán)利用。實(shí)驗(yàn)結(jié)果表明,穩(wěn)定的剝離過程可以為h-BN基層狀材料的一系列重要應(yīng)用開辟道路。進(jìn)一步實(shí)驗(yàn)中利用新鮮制備的氯化四氨合銅,氯化六氨合鈷和氯化六氨合鎳等做為金屬前驅(qū)體,與硼氫化鉀混合球磨得到熱分解前驅(qū)體,然后在900℃、氮?dú)夥諊卤簾?h制備出少層六方氮化硼分別包裹納米銅、鈷、鎳及鈷鎳合金(M@h-BN)的復(fù)合材料,實(shí)現(xiàn)了少層h-BN(約5?15層)的一步合成及具有規(guī)定尺寸的金屬納米粒子的同步還原。其中CoNi@h-BN表現(xiàn)出較好的催化氨硼烷析氫的活性與穩(wěn)定性,實(shí)驗(yàn)測(cè)得的活化能Ea為28 kJmol-1,低于文獻(xiàn)報(bào)道的大多數(shù)金屬基催化劑的活化能(Ea)。性能的提高歸因于封裝后CoNi NPs的電子結(jié)構(gòu)變化以及h-BN和氨硼烷的基本位點(diǎn)之間的強(qiáng)相互作用。此外,CoNi@h-BN表現(xiàn)的軟磁性可以容易地循環(huán)利用,并保持高催化活性甚至再循環(huán)5次。Co@h-BN,Ni@h-BN,Cu@h-BN)復(fù)合材料表現(xiàn)出較強(qiáng)的熱穩(wěn)定性、磁性和較高的導(dǎo)熱系數(shù)。尤其是Cu@h-BN的導(dǎo)熱系數(shù)為253.7 Wm-1K-1,其熱穩(wěn)定性可以高達(dá)414℃,復(fù)合樣品優(yōu)異的性能為小巧或封裝級(jí)的電子設(shè)備的熱管理提出潛在解決方案。結(jié)合DSC-TG分析和物理化學(xué)表征結(jié)果,提出了M@h-BN的可能形成機(jī)理。同時(shí),這種新型合成策略有望在電化學(xué)傳感器,高導(dǎo)熱粘合劑材料和燃料電池領(lǐng)域獲得應(yīng)用。
[Abstract]:As a new two-dimensional nanomaterials discovered in recent years, h-BN nanomaterials have many excellent physical and chemical properties, which make them in the treatment of environmental water pollution, renewable energy industrialization, At present, the preparation of layered h-BN with high quality and industrial amplification has become a limiting factor for the commercial application of boron nitride. In this paper, commercial h-BN powder is used as precursor. Low-cost and high-yield h-BNs were developed by using sodium hypochlorite aqueous solution assisted ball-milling stripping method. This method can obtain less layer 2-4 layers of h-BN, and the in-plane structure of h-BN layer is less damaged. The yield of the product was as high as 21. The reduction of p-nitrophenol to p-aminophenol was effectively catalyzed in the presence of NaBH4 on the basis of a few layers of h-BN as the carrier of Ag nanoparticles, and the reduction of p-nitrophenol to p-aminophenol was effective in the presence of H-BN. The obtained first-order reaction rate constant is 7.13 脳 10-3s-1, which is larger than the first-order reaction rate constant of commercial h-BN-loaded Ag nanoparticles, and the catalyst has good stability and can be recycled. The stable peeling process can open the way for a series of important applications of h-BN base-like materials. In further experiments, freshly prepared copper tetraamides, cobalt hexaaminochloride and nickel hexaaminochloride are used as metal precursors. The thermal decomposition precursor was prepared by mixing it with potassium borohydride, and then calcined at 900 鈩，

本文編號(hào)：1561030