本文選題：可見光　切入點(diǎn)：催化　出處：《東華大學(xué)》2015年碩士論文

【摘要】：太陽(yáng)能光催化分解水制氫是21世紀(jì)人類從根本上解決日益嚴(yán)峻的能源與環(huán)境問題較為理想的途徑之一，已引起了各國(guó)研究者的高度關(guān)注。然而，目前所研究的光催化材料大都只能在紫外光下有光催化響應(yīng)。由于N2p軌道能級(jí)比O2p軌道能級(jí)高，多數(shù)過渡金屬氧化物氮化為氧氮化物后，在可見光區(qū)呈現(xiàn)較強(qiáng)的吸收能力，是一種潛在的具有可見光響應(yīng)能力的光催化材料。近年來，開發(fā)和研制在可見光區(qū)具有高活性的過渡金屬氧氮化物光催化劑成為光催化的研究前沿。本論文以過渡金屬氧化物為原料，通過氮化反應(yīng)制備出具有窄能隙的、可見光響應(yīng)的光催化劑納米TaON，論文的主要內(nèi)容有： 采用高溫氣固相反應(yīng)，以Ta2O5為原料，通過氮化反應(yīng)制備TaON。采用X-射線衍射（XRD）分析、場(chǎng)發(fā)射掃描電子顯微鏡（FESEM）、紫外－可見(UV-VIS)漫反射光譜分析、氮?dú)馕?脫附分析等測(cè)試手段對(duì)所制備的光催化劑進(jìn)行了表征，結(jié)果表明：在反應(yīng)溫度為850℃，氨氣流量為90ml/min，氮化10h可制得純相的TaON。通過改變催化劑的形貌，增大比表面積，進(jìn)而提高催化劑的活性，制得了細(xì)顆粒TaON、多孔TaON及纖維狀TaON中，其中細(xì)顆粒TaON具有最大的比表面積，達(dá)到109.2m2/g，光催化活性最高，將初始濃度為50PPm的亞甲基藍(lán)溶液在可見光照射下120min，，濃度降低了96%，具有最好的光催化活性。 為降低TaON的缺陷密度，在細(xì)顆粒Ta2O5粉體表面復(fù)合一層ZrO2納米顆粒，氮化得到了ZrO2/TaON復(fù)合材料。界面處的鉭離子與ZrO2相互作用，有效抑制了低價(jià)鉭離子的形成。為了進(jìn)一步提高ZrO2/TaON復(fù)合光催劑的活性，于ZrO2/TaON的表面負(fù)載RuO2為助催化劑，用XRD、SEM和TEM等表征，證明在TaON表面成功包覆了ZrO2和RuO2顆粒，用光電流及光催化制氫反應(yīng)器評(píng)價(jià)了復(fù)合材料的光催化性能，在RuO2含量為2wt%時(shí)活性最高，產(chǎn)氫速率為5umol/h。 以鉭粉為原料，采用水熱法制備了無定型的Ta2O5，經(jīng)氮化、氮化后再氧化得到高活性的γ-TaON，并與CdS復(fù)合形成異質(zhì)結(jié)結(jié)構(gòu)。為抑制CdS在水溶液中的光腐蝕，在其表面包覆一層ZnS。采用X射線衍射儀（XRD）、場(chǎng)發(fā)射掃描電子顯微鏡（FESEM）和透射電子顯微鏡（TEM）對(duì)復(fù)合材料進(jìn)行表征，表明ZnS/CdS顆粒成功的包覆在γ-TaON光催化劑的表面。光電流結(jié)果表明其活性大幅提高。在可見光照射下，ZnS/CdS/γ-TaON復(fù)合光催化劑在甲酸溶液中表現(xiàn)出最高的活性；當(dāng)ZnS/CdS的含量為20wt%時(shí)，產(chǎn)氫速率達(dá)到了20umol/h。
[Abstract]:Photocatalytic decomposition of water for hydrogen production by solar energy is one of the ideal ways to solve the increasingly serious energy and environmental problems in the 21st century, which has attracted the attention of researchers all over the world. At present, most of the photocatalytic materials studied can only have photocatalytic response under ultraviolet light. Because the N 2p orbital energy level is higher than that of O 2p orbital energy level, most transition metal oxides nitrided into oxygen nitride, showing strong absorption ability in the visible light region. Is a potential photocatalytic material with visible light response. In recent years, In this paper, transition metal oxide photocatalysts with high activity in visible light region have been developed and developed. In this paper, transition metal oxides were used as raw materials to prepare transition metal oxide photocatalysts with narrow energy gap. Visible light responsive photocatalyst nano-TaON, the main contents of the paper are:. TaON was prepared by nitriding reaction with high temperature gas-solid reaction and Ta2O5. The results were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), UV-Vis (UV-VIS) diffuse reflectance spectroscopy. The photocatalysts were characterized by nitrogen adsorption-desorption analysis. The results showed that the pure phase TaON could be obtained by changing the morphology of the catalyst and increasing the specific surface area at 850 鈩

本文編號(hào)：1675365