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以钛酸丁酯为钛源,用醇热法制备了N、Fe单掺杂及共掺杂纳米TiO_2。对样品的晶型结构、表面形貌、比表面积、紫外可见吸收、光致发光和分解水制氢催化性能分别进行了表征。结果表明,在500℃退火的N、Fe共掺杂TiO_2样品均为锐钛矿相棱形纳米颗粒,分散性较好,平均粒径约20 nm;N、Fe共掺杂的摩尔分数分别为5.0%和2.0%时,样品具有良好的可见光吸收活性,对光的吸收从387 nm(未掺杂锐钛矿相TiO_2)红移至510 nm处。主要原因可能是,N和Fe共掺杂在其禁带中产生杂质能级,导致其禁带宽度减小;N、Fe单掺杂及共掺杂改性,有效抑制了电子-空穴的复合,提高了光生载流子的分离效率;在可见光下(λ>400 nm)N、Fe共掺杂TiO_2具有较高的光催化分解水制氢活性,氢气生成速率为299.2μmol·g~(-1)·h~-1。
N, Fe single-doped and co-doped nano-TiO 2 were prepared by thermal titration with butyl titanate as titanium source. The crystal structure, surface morphology, specific surface area, UV-Vis absorption, photoluminescence and hydrogen catalytic properties of the samples were characterized respectively. The results show that the samples with N and Fe co-doped TiO 2 annealed at 500 ℃ are all anatase phase prismatic nanoparticles with good dispersibility and average particle size of about 20 nm. The molar fractions of co-doped N and Fe are 5.0% and 2.0%, the sample has good visible light absorption activity, the absorption of light red-shifted from 387 nm (undoped anatase phase TiO 2) to 510 nm. The main reason may be that N and Fe co-doping generate impurity levels in the forbidden band, resulting in a decrease of the forbidden band width. N, Fe single doping and co-doping modification effectively inhibit electron-hole (Λ> 400 nm) N, Fe co-doped TiO 2 has high activity of photocatalytic decomposition of water to produce hydrogen, hydrogen generation rate of 299.2 μmol · g ~ ( -1) · h ~ -1.