本文選題：鉭酸鹽 + 光催化��； 參考：《中國(guó)地質(zhì)大學(xué)(北京)》2017年碩士論文

【摘要】：人類(lèi)社會(huì)面臨著能源和環(huán)境問(wèn)題,光催化材料可以有效的利用太陽(yáng)能,既可以裂解水制取氫氣,也可以應(yīng)用在環(huán)境治理中,可以有效的降解水體中的有機(jī)污染物,這種環(huán)保無(wú)污染的技術(shù),有希望解決未來(lái)的能源問(wèn)題以及環(huán)境污染問(wèn)題。迄今為止所研究的光催化劑中,鈣鈦礦型光催化劑以它特有的結(jié)構(gòu)在光催化領(lǐng)域具有較大的應(yīng)用前景,鈣鈦礦型鉭酸鹽材料顯示了好的光分解水制氫性能,本文采用熔鹽法制備了NaTaO_3納米催化劑,探討了熱處理溫度、升溫速率、保溫時(shí)間和Nb的摻雜對(duì)NaTaO_3物相、形貌和性能的影響,并研究了Sr的摻雜以及NiO的復(fù)合對(duì)NaNb_(0.5)Ta_(0.5)O_3物相、形貌、催化性能和電化學(xué)的影響。研究結(jié)果表明,熱處理溫度為750℃,升溫速率為5 ℃/min,保溫時(shí)間為2h,在這個(gè)制備條件下,可以得到結(jié)晶良好,微觀相貌為20-50 nm的NaTaO_3立方形貌。NaTaO_3具有較高的光催化活性,產(chǎn)氫速率最高分別為0.57 mmol/h/g。通過(guò)選用Nb元素對(duì)NaTaO_3B位摻雜,選用Sr元素對(duì)NaNb_(0.5)Ta_(0.5)O_3 A位摻雜,通過(guò)NiO的負(fù)載在NaNb_(0.5)Ta_(0.5)O_3立方體表面分別合成NaNbxTa_(1-x)O_3,Sr_xNa_(1-2x)Nb_(0.5)Ta_(0.5)O_3,NiO/NaNb_(0.5)Ta_(0.5)O_3光催化劑。通過(guò)光催化制氫性能、光催化降解污染物性能和電化學(xué)性能研究表明,Nb元素進(jìn)入晶體結(jié)構(gòu)中,獲得了優(yōu)化后的Nb~(5+)摻雜量為0.5,NaNb_(0.5)Ta_(0.5)O 36 h制備氫氣為14.59 mmol/g,產(chǎn)生的氫氣總量是NaTaO_3的3.8倍,在光照40 min后降解96%的羅丹明B,50 min后完全降解,降解效率最高。優(yōu)化得到了Sr~(2+)摻雜量為3%,Sr_xNa_(1-2x)Nb_(0.5)Ta_(0.5)O_3樣品的制氫量最高為18.56 mmol/g,制氫速率為3.09 mmol/h/g。通過(guò)NiO的負(fù)載在NaNb_(0.5)Ta_(0.5)O_3立方體表面,NiO/NaNb_(0.5)Ta_(0.5)O_3的吸收邊發(fā)生了紅移,擴(kuò)寬了光催化劑的光響應(yīng)范圍。獲得了優(yōu)化后的NiO的負(fù)載量為3%,3%NiO/NaNb_(0.5)Ta_(0.5)O_3樣品的6 h制氫量為26.70 mmol/g,穩(wěn)定后的制氫速率為4.45 mmol/h/g,同樣是是NaNb_(0.5)Ta_(0.5)O_3的1.83倍。
[Abstract]:Human society is faced with energy and environmental problems, photocatalytic materials can effectively use solar energy, not only can split water to produce hydrogen, but also can be used in environmental control, can effectively degrade organic pollutants in water. This environmentally-friendly and non-polluting technology promises to solve future energy and environmental pollution problems. So far, perovskite photocatalyst has a great application prospect in the field of photocatalysis because of its unique structure. Perovskite tantalate materials show good performance of photodecomposition of water to produce hydrogen. In this paper, NaTaO_3 nanocatalysts were prepared by molten salt method. The effects of heat treatment temperature, heating rate, holding time and NB doping on the phase, morphology and properties of NaTaO_3 were investigated. The phase and morphology of NaNb_(0.5)Ta_(0.5)O_3 were also studied by Sr doping and NiO composite. Effects of catalysis and electrochemistry. The results show that the NaTaO_3 cubic morphology. NaTaOs _ 3 with a microstructure of 20-50 nm has high photocatalytic activity under the condition that the heat treatment temperature is 750 鈩，

本文編號(hào)：1973654