Fe3＋掺杂NaTaO3纳米粒子的制备及光吸收机理

摘要

Pure and Fe-doped NaTaO3 nanoparticles were synthesized by hydrothermal method.XRD patterns indicated that both pure as well as iron doped NaTaO3 were pure orthorhombic phase of tantalite.UV-vis diffuse reflectance spectra clearly displayed the red-shift in the series of iron doped NaTaO3 catalysts,indicating a decrease in the band gap of NaTaO3 caused by the substitution of Fe3＋ ions at Ta5＋ site,and the red-shift increased with the increase of iron doping concentration in NaTaO3. The light absorption mechanism was discussed by density functional theory.Fe3＋ ions substitution of Ta5＋ ions resulted in an intermediate band（IB） below the bottom of the conduction band（CB）,which was mainly attributed to the state of Fe 3d.%采用水热法合成了一系列铁离子掺杂NaTaO3纳米粒子,研究了铁离子掺杂对宽禁带钽酸钠半导体光吸收性能的影响。XRD结果表明铁离子掺杂导致NaTaO3晶胞体积膨胀;紫外可见漫反射光谱表明铁离子掺杂引起钽酸钠吸收带边红移,并且随着铁离子掺杂浓度的增加,红移增大;密度泛函计算结果揭示,铁离子取代钽离子进入NaTaO3晶格会形成一个杂质能级,这个杂质能级主要由铁离子的3d轨道形成,是导致NaTaO3光吸收带边红移的原因。