(1.清華大學(xué)深圳研究院 低碳能源與節(jié)能技術(shù)重點(diǎn)實(shí)驗(yàn)室，深圳 518057；
2. 中南大學(xué) 粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083)
摘 要: 采用電化學(xué)陽(yáng)極氧化法制備TiO2納米管陣列，分別在O2、N2、5%H2+95%N2(體積分?jǐn)?shù))和NH3氣氛中于400~650 ℃退火處理，初步實(shí)現(xiàn)TiO2納米管中銳鈦礦向金紅石相轉(zhuǎn)變的可控制備。采用FESEM、XRD、Raman對(duì)退火處理后TiO2納米管的表面形貌、結(jié)構(gòu)以及相轉(zhuǎn)變等進(jìn)行表征。結(jié)果表明：隨著退火溫度的升高，在O2氣氛退火時(shí)，源于Ti基體的吞噬效應(yīng)(Feeding effect)是導(dǎo)致TiO2相轉(zhuǎn)變的主要原因；在N2和(5%H2+95%N2)氣氛退火后，氧空位加速了銳鈦礦向金紅石相的轉(zhuǎn)變；而在NH3氣氛中退火后，N摻雜則有效抑制了銳鈦礦向金紅石相的轉(zhuǎn)變。在此基礎(chǔ)上，對(duì)其相轉(zhuǎn)變機(jī)理進(jìn)行了初步探討，為進(jìn)一步制備具有可控相含量及微觀點(diǎn)缺陷的TiO2半導(dǎo)體和高性能器件提供了有益思路。
關(guān)鍵字: TiO2納米管；陽(yáng)極氧化；摻雜；可控相轉(zhuǎn)變
（1. Key Laboratory of Low-carbon Energy and Energy-saving Technology,
Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057, China;
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:TiO2 nanotube arrays were prepared by electrochemical anodic oxidation method. Controllable anatase to rutile phase transformation (ARPT) was realized by annealing anodic TiO2 nanotube arrays (TNTs) in O2, N2, 5%H2+95%N2 (volume fraction) and NH3 atmospheres at temperature range of 400-650 ℃. FESEM, XRD and Raman were used to characterize the surface morphology, structure and phase transformation of the annealed TNTs in different atmospheres and temperatures. The results show that the “feeding effect” is mainly responsible for the ARPT of TNTs annealed in O2 with increasing the annealing temperature. Oxygen vacancies induced by N2 and (5%H2+95%N2) atmospheres accelerate the ARPT. Annealing in ammonia efficiently slows down the ARPT due to the N-doping. ARPT mechanisms were further investigated. These results provide us an efficient method to extend the study of synthesis of TiO2 semiconductors and high performance devices with controllable phase contents and point defects.
Key words: TiO2 nanotube; anodization; doping; controllable phase transformation
