本文選題：木材 + 納米纖維素�。� 參考：《東北林業(yè)大學(xué)》2015年碩士論文

【摘要】：本研究利用廢棄木粉資源為原料,通過酸水解法和超聲分離法制備出高長徑比和高結(jié)晶度的纖維素納米晶須(CNW)和纖維素納米纖絲(CNF),并探究其作為環(huán)境友好型柔性透光電器膜和生物碳復(fù)合電極材料的應(yīng)用潛力。在環(huán)境友好型柔性透光電器膜的研究中,將CNW通過抽濾成膜,既而在其表面層層抽濾沉積石墨烯后熱壓干燥成膜,對所形成的復(fù)合膜的結(jié)構(gòu)、熱力學(xué)性能和光電性能進行測試分析。在生物碳復(fù)合電極材料的研究中,以CNF為碳源,乙酸錳為錳源,對二者冷凍干燥形成的復(fù)合氣凝膠進行碳化,制備出具有三維結(jié)構(gòu)和豐富孔隙的復(fù)合電極材料,并對其結(jié)構(gòu)和電化學(xué)性能進行測試分析。研究得到以下結(jié)論：(1)以CNW作為基底膜,克服了單層或多層石墨烯不能自持的缺點,所形成的復(fù)合膜具有良好的透光性、導(dǎo)電性、柔韌性、可折疊性、高模量和耐高溫的特點�；谡婵粘闉V方法的成膜工藝簡單,可控性強。通過控制CNW和石墨烯的加入量,可以調(diào)節(jié)復(fù)合膜的厚度、透光性和導(dǎo)電性能。隨石墨烯沉積層數(shù)的增多,復(fù)合膜的電阻值逐漸減小,導(dǎo)電率逐漸升高；而透光率逐漸下降。復(fù)合三層石墨烯所形成的復(fù)合膜,具有適中的導(dǎo)電性能(2.8 S/cm)和透光性能(53%),楊氏模量為10.2 GPa,斷裂功達472.2 KJ/m,并在室溫至280℃區(qū)間內(nèi)具有良好的熱穩(wěn)定性。(2)CNF和乙酸錳的溶液均相混合,解決了直接加入MnO2粉末所導(dǎo)致的分散不均、顆粒團聚的問題。通過冷凍干燥及碳化工藝,制備的MnOx/CNF復(fù)合體系具有三維孔隙的自支撐結(jié)構(gòu),其孔隙率可由混合液的濃度控制。高比表面積和豐富的孔隙為電解液的擴散提供連續(xù)通道,表面生長的MnOx與電解液接觸的接觸面積增加,增加了電極材料的浸潤性,縮短電解液的擴散路徑,可減小電荷轉(zhuǎn)移阻抗和Warburg阻抗,從而達到提高綜合電容性能的目的。隨著復(fù)合體系中錳源含量增加,MnOx/CNF復(fù)合體系的比電容增加,且比電容的增加值較為均勻。當(dāng)錳源含量為40%時,復(fù)合體系具有較高的比電容值(在掃描速率為2 mVs-1時,其比電容可達138.4 Fg-1)和倍率特性,表現(xiàn)出優(yōu)異的綜合電化學(xué)性能。在電流密度為lAg-1下經(jīng)過200次充放電后復(fù)合材料的比電容量衰減約10%,充放電次數(shù)500次時比電容量衰減為17%,其后隨著循環(huán)次數(shù)的增加比電容的降低速度減緩,表明該電極材料具有較好的的循環(huán)穩(wěn)定性。
[Abstract]:In this study, waste wood flour was used as raw material. Cellulose nanocrystalline whiskers with high aspect ratio and high crystallinity were prepared by acid hydrolysis and ultrasonic separation, and their potential applications as environmentally friendly flexible transparent film and biocarbon composite electrode materials were investigated. In the study of environment-friendly flexible transparent electric apparatus membrane, CNW was filtered into film, and then the composite film was formed by hot pressing and drying on the surface of the film. Thermodynamic and photoelectric properties were tested and analyzed. In the study of biological carbon composite electrode materials, the composite aerogels, which were formed by freeze-drying, were carbonized with CNF as carbon source and manganese acetate as manganese source, and the composite electrode materials with three-dimensional structure and rich pores were prepared. The structure and electrochemical performance were tested and analyzed. The following conclusions are obtained: (1) using CNW as the substrate membrane, it overcomes the shortcoming that single or multilayer graphene can not sustain itself, and the composite film has the characteristics of good transmittance, conductivity, flexibility, foldable, high modulus and high temperature resistance. The film forming process based on vacuum filtration method is simple and controllable. The thickness, transmittance and conductivity of the composite film can be adjusted by controlling the amount of CNW and graphene. With the increase of graphene deposition layer, the resistance of the composite film decreases gradually, the conductivity increases and the transmittance decreases. The composite membrane formed by the composite three-layer graphene has moderate electrical conductivity (2.8s / cm) and light transmittance. The Young's modulus is 10.2GPa. the fracture work is 472.2 KJ / m, and it has good thermal stability and homogeneous mixing with manganese acetate solution in the range of room temperature to 280 鈩，

本文編號：1900491