SINGLE CRYSTAL GROWTH OF ANATASE TiO2 AND DEPENDENCE OF ITS ELECTRIC AND OPTICAL PROPERTIES ON THE MOLPHOLOGY AND OXYGEN DEFECTS.

锐钛矿型 TiO2 的单晶生长及其电学和光学性质对形态和氧缺陷的依赖性。

• 批准号: 08454080
• 负责人: KURITA Susumu
• 金额: $ 5.31万
• 依托单位: YOKOHAMA NATIONAL UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08454080/
• 关键词: TITANIUM DIOXIDE; ANATASE; SINGLE CRYSTAL GROWTH; OPTICAL PROPERTY; OXYGEN DEFECT; EXCITON; 電気伝導; 励起子

THE METHOD OF SINGLE CRYSTAL GROWTH OF ANATASE TiO2 HAS BEEN INVESTIGATED ON THE BASE OF THE CHMICAL VAPOR TRANSPORT REACTION.THE MOST SUCCESSFUL CONDITON OF CRYSTAL GROWTH IS THAT TRANSPORT AGENT OF NH_4Cl, TEMPERATURE OF TEH SOURCE OF SEALED AMPOULE AND TEH GROWING PART WERE 750-800ﾟC AND 650-700ﾟC,RESPECTIVELY.CRYSTALS OF ABOUT 2x2x3mm^3 IN SIZE THAT WERE OCTAHEDRON SHAPED IN COLOR OF TRANSPARENT PALE BLUE WERE GROWN.(1) POLARIZED REFLECION SPECTRA OF THREE CRYSTALLINE MODEFICATIONS OF RUTILE,ANATASE AND BROOKITE,WERE MEASURED FOR THE PHOTON ENERGY RANGE OF 2-25eV USING SYNCHROTRON ORBITAL RADIATION.THE DIFFERENCE IN THE SPECTRAL FEATURE IS DISCUSSED ON THE BASIS OF THE CRYSTAL SRUCTURE OF THE MODIFICATIONS.(2) THE ANATASE HAS THE DIRECT ALLOWED TRANSITION GAP AND THE ABSORPTION TAIL SHOWS URBACH RULE.THE STEEPNESS INDEX OBTAINED INDICATES THAT AN EXCITON IS SELF-TRAPPED AFTER THE RELAXATION.(3) IN THE ANATASE PHASE WITH OXYGEN VACANCY,AN ABSORPTION BNAD POLARIZED MAINLY E//a APPEARS AT THE PEAK OF 3.0eV.THE VACANCY DISAPPEARS AFTER HEAT-TREATMENT OF 48HRS AT 800ﾟC ON THE OXYGEN PRESSURE OF 1MPa. (4) BROAD LUMINESCENCE WAS OBSERVED WITH PEAKS AT AROUND 2.1 AND 2.3eV WHICH ARE FROM THE SELF-TRAPPED EXCITONS.

研究了基于化学气相传输反应的锐钛矿型TiO2单晶生长方法。晶体生长最成功的条件是NH_4Cl传输剂、密封安瓿源温度和生长温度。部分温度分别为 750-800ﾟC 和 650-700ﾟC。晶体大小约为 2x2x3mm^3，呈八面体颜色 (1)利用同步加速器轨道辐射测量了金红石、锐钛矿和板钛矿三种晶型在2-25eV光子能量范围内的偏振反射光谱。在改性的晶体结构的基础上讨论了其特点。(2)锐钛矿具有直接允许的过渡间隙和吸收拖尾现象 乌尔巴赫法则。得到的陡度指数表明弛豫后激子是自陷的。(3)在有氧空位的锐钛矿相中，在3.0eV峰值处出现了以E//a为主的吸收BNAD偏振，空位消失后氧压1MPa、800℃热处理48小时。 (4) 观察到广泛的发光，其峰值位于 2.1 和 2.3eV 左右，这些峰值来自自陷激子。

项目成果

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T.Sekiya 等人：“TiO_2 单晶反射光谱的结构依赖性”。J.Elect.Spectrosc.Relat.Phenom。（正在出版）。

N.Hosaka et al.: "Optical properties of single crystal anatase TiO_2." J.Phys.Soc.Jpn.66(印刷中). (1997)

N.Hosaka 等人：“单晶锐钛矿 TiO_2 的光学特性。”J.Phys.Soc.Jpn.66（出版中）。

N.Hosaka, T.Sekiya, M.Fujisawa, C.Satoko and S.Kurita: "UV reflection spectra of anatase TO_2." J.Electron Spectrose. Relat, Phenom. Vol.78. 75-78 (1996)

N.Hosaka、T.Sekiya、M.Fujisawa、C.Satoko 和 S.Kurita：“锐钛矿 TO_2 的紫外反射光谱。”

N.Hosaka, T.Sekiya, C.Satoko and S.Kurita: "Optical properties of anatase TiO_2 single crystal" J.Phys.Soc.Jpn. Vol.66. 877-880 (1997)

N.Hosaka、T.Sekiya、C.Satoko 和 S.Kurita：“锐钛矿 TiO_2 单晶的光学特性”J.Phys.Soc.Jpn。

N.Hosaka et al.: "Excitonic state in anatase TiO_2 single crystal." J.Lumin.(印刷中).

N. Hosaka 等人：“锐钛矿 TiO_2 单晶中的激子态”（J. Lumin）。