同步辐射软X射线吸收谱与发射谱测定天然针铁矿能带结构
|
摘要
天然半导体矿物由于成分、缺陷复杂,传统测试方法如紫外可见漫反射等难以准确测定其禁带宽度.本文以针铁矿为例,通过第一性原理计算得到纯针铁矿及掺Al针铁矿的电子结构.计算结果显示,纯针铁矿导带底与价带顶均由Fe3d与O2p轨道组成,而当含杂质Al时,Al2p与O2p发生杂化参与了价带组成.在此基础上,利用同步辐射X射线氧的K边吸收谱与发射谱对纯针铁矿及天然针铁矿的能带结构进行了测定.结果表明,天然含Al的针铁矿禁带宽度为2.30eV,小于纯针铁矿(2.57eV).本研究提供了一种测定天然氧化物矿物禁带宽度的新方法,为深入研究天然半导体可见光催化活性产生机制提供了理论依据.
In this study, the authors investigated the electronic structures of natural goethite FeOOH by first principle theory and synchrotron soft X-ray emission and absorption spectroscopy. The results show that the band gap of natural goethite FeOOH is 2. 30 eV, smaller than the band gap of pure goethite FeOOH( 2. 57 eV). Due to the complex compositions and plenty of defects, the band structure of natural minerals is hard to measure by traditional methods, such as UV-Vis. The results supply a new way for determining the band structure of natural semiconductor minerals and also provide a basis for better understanding of photocatalytic mechanism of them under visible light.
In this study, the authors investigated the electronic structures of natural goethite FeOOH by first principle theory and synchrotron soft X-ray emission and absorption spectroscopy. The results show that the band gap of natural goethite FeOOH is 2. 30 eV, smaller than the band gap of pure goethite FeOOH( 2. 57 eV). Due to the complex compositions and plenty of defects, the band structure of natural minerals is hard to measure by traditional methods, such as UV-Vis. The results supply a new way for determining the band structure of natural semiconductor minerals and also provide a basis for better understanding of photocatalytic mechanism of them under visible light.
引文
Choi W Y,Termin A and Hoffmann M R.1994.The role of metal ion dopants in quantum-sized TiO 2:Correlation between photoreactivity and charge carrier recombination dynamics[J].Journal of Physical Chemistry,98(61):13 669~13 679.
Ding Cong,Li Yan and Lu Anhuai.2015.The electronic structures of Feand Cd-doped sphalerite Zn S from first principles calculations[J].Acta Petrologica et Mineralogica,34(3):382~386(in Chinese with English abstract).
Fuente S A,Belelli P G and Castellani N J.2013.LDA+U and GGA+U studies of Al-rich and bulk goethite(α-FeO OH)[J].Materials Chemistry and Physics,137:1 012~1 020.
Huang W H,Sun S J,Chiou J W,et al.2011.Electronic structure o Al-doped Zn O transparent conductive thin films studied by x-ray absorption and emission spectroscopies[J].Journal of Applied Physics,110:103 705.
Kresse G and Furthmuller J.1996.Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set[J].Physica Reveiw B,54(16):11 169~11 186.
Kurmaev E Z,Wilks R G and Moewes A.2008.Oxygen x-ray emission and absorption spectra as a probe of the electronic structure of strongly correlated oxides[J].Physical Review B,77:165 127.
Li Yan,Lu Anhuai and Wang Changqiu.2007.Visible light-induced photoreductive activity of natural Fe-bearing Sphalerite[J].Acta Petrologica et Mineralogica,26(6):481~486(in Chinese with English abstract).
Lu Anhuai,Guo Yanjun and Liu Juan.2004.Natural rutile:A photocatalysis to degrade organic pollutants[J].Chinese Science Bulletin,49(22):2 350~2 352(in Chinese).
Martin G J,Cutting R S,Vaughan D J,et al.2009.Bulk and key surface structure of hematite,magnetite,and goethite:A density functional theory study[J].American Mineralogist,94:1 341~1 350.
Nakamura R,Tanaka T and Nakato Y.2004.Mechanism for visible light responses in anodic photocurrents at N-doped Ti O2film electrodes[J].Journal of Physical Chemistry B,108(30):10 617~10 620.
Sherman D M.2005.Electronic structures of iron(Ⅲ)and manganese(Ⅳ)(hydr)oxide minerals:Thermodynamics of photochemical reductive dissolution in aquatic environments[J].Geochimica et Cosmochimica Acta,69(13):3 249~3 255.
Wu Jing,Wu Xiang,Zhu Feng,et al.2012.The electronic structures o Fe-and V-doped rutile TiO 2from first principles calculations[J].Acta Petrologica et Mineralogica,31(3):441~446(in Chinese with English abstract).
Xu Y and Schoonen M A A.2000.The absolute energy positions of conduction and valence bands of selected semiconducting minerals[J].American Mineralogist,85:543~556.
Yamashita H,Harada M,Misaka J,et al.2003.Photocatalytic degradation of organic compounds diluted in water using visible light-responsive metal ion-implanted TiO 2catalysts:Fe ion-implanted TiO 2[J].Catalysis Today,84(3~4):191~196.
丁聪,李艳,鲁安怀.2015.掺杂Fe、Cd闪锌矿电子结构的第一性原理计算[J].岩石矿物学杂志,34(3):382~386.
李艳,鲁安怀,王长秋.2007.天然含铁闪锌矿的可见光催化还原活性研究[J].岩石矿物学杂志,26(6):481~486.
鲁安怀,郭延军,刘娟.2004.天然含钒金红石:一种用于降解卤代有机污染物的光催化剂[J].科学通报,49(22):2 350~2 352.
吴婧,巫翔,朱峰,等.2012.掺Fe和V的金红石电子结构的第一性原理计算研究[J].岩石矿物学杂志,31(3):441~446.
Ding Cong,Li Yan and Lu Anhuai.2015.The electronic structures of Feand Cd-doped sphalerite Zn S from first principles calculations[J].Acta Petrologica et Mineralogica,34(3):382~386(in Chinese with English abstract).
Fuente S A,Belelli P G and Castellani N J.2013.LDA+U and GGA+U studies of Al-rich and bulk goethite(α-FeO OH)[J].Materials Chemistry and Physics,137:1 012~1 020.
Huang W H,Sun S J,Chiou J W,et al.2011.Electronic structure o Al-doped Zn O transparent conductive thin films studied by x-ray absorption and emission spectroscopies[J].Journal of Applied Physics,110:103 705.
Kresse G and Furthmuller J.1996.Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set[J].Physica Reveiw B,54(16):11 169~11 186.
Kurmaev E Z,Wilks R G and Moewes A.2008.Oxygen x-ray emission and absorption spectra as a probe of the electronic structure of strongly correlated oxides[J].Physical Review B,77:165 127.
Li Yan,Lu Anhuai and Wang Changqiu.2007.Visible light-induced photoreductive activity of natural Fe-bearing Sphalerite[J].Acta Petrologica et Mineralogica,26(6):481~486(in Chinese with English abstract).
Lu Anhuai,Guo Yanjun and Liu Juan.2004.Natural rutile:A photocatalysis to degrade organic pollutants[J].Chinese Science Bulletin,49(22):2 350~2 352(in Chinese).
Martin G J,Cutting R S,Vaughan D J,et al.2009.Bulk and key surface structure of hematite,magnetite,and goethite:A density functional theory study[J].American Mineralogist,94:1 341~1 350.
Nakamura R,Tanaka T and Nakato Y.2004.Mechanism for visible light responses in anodic photocurrents at N-doped Ti O2film electrodes[J].Journal of Physical Chemistry B,108(30):10 617~10 620.
Sherman D M.2005.Electronic structures of iron(Ⅲ)and manganese(Ⅳ)(hydr)oxide minerals:Thermodynamics of photochemical reductive dissolution in aquatic environments[J].Geochimica et Cosmochimica Acta,69(13):3 249~3 255.
Wu Jing,Wu Xiang,Zhu Feng,et al.2012.The electronic structures o Fe-and V-doped rutile TiO 2from first principles calculations[J].Acta Petrologica et Mineralogica,31(3):441~446(in Chinese with English abstract).
Xu Y and Schoonen M A A.2000.The absolute energy positions of conduction and valence bands of selected semiconducting minerals[J].American Mineralogist,85:543~556.
Yamashita H,Harada M,Misaka J,et al.2003.Photocatalytic degradation of organic compounds diluted in water using visible light-responsive metal ion-implanted TiO 2catalysts:Fe ion-implanted TiO 2[J].Catalysis Today,84(3~4):191~196.
丁聪,李艳,鲁安怀.2015.掺杂Fe、Cd闪锌矿电子结构的第一性原理计算[J].岩石矿物学杂志,34(3):382~386.
李艳,鲁安怀,王长秋.2007.天然含铁闪锌矿的可见光催化还原活性研究[J].岩石矿物学杂志,26(6):481~486.
鲁安怀,郭延军,刘娟.2004.天然含钒金红石:一种用于降解卤代有机污染物的光催化剂[J].科学通报,49(22):2 350~2 352.
吴婧,巫翔,朱峰,等.2012.掺Fe和V的金红石电子结构的第一性原理计算研究[J].岩石矿物学杂志,31(3):441~446.