Preparation and ultrafast carrier dynamics of semiconductor nanoparticles

半导体纳米颗粒的制备及超快载流子动力学

• 批准号: 15510098
• 负责人: TOYODA Taro
• 金额: $ 2.37万
• 依托单位: The University of Electro-Communications
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15510098/
• 关键词: semiconductor nanoparticles; TiO_2 nanoparticles; ZnS nanoparticles; photovoltaic phenomena; luminescence properties; photoacoustic spectrum; photoelectrochemica spectrum; transient characterization; 光電変換; 光音響法; 光化学電流法; TiO_2ナノ粒子; SnO_2ナノ粒子

Significant progress in solar cell application has been made since 1990's using nanostructured TiO_2 electrodes adsorbed with organic dyes (DSSC). In addition to organic dyes, semiconductor quantum dots (QDs) have also attracted much interest as light harvesters in DSSC. In this study, we prepared nanostructured TiO_2 electrodes with different morphologies. We adsorbed CdSe QDs onto the electrodes as photosensitizers. Characterization by photoacoustic (PA), photoelectrochemical current (PEC), and transient grating (TG) methods were applied. Redshoft of the PA spectrum with the increase of CdSe QDs adsorption time can be clearly observed and the PEC spectrum showed the photosensitization in the visible region resulting from the QDs adsorption. The decay time of excited electrons in the CdSe QDs was different with each nanostructured TiO_2 electrodes with different morphologies, reflecting the difference of crystal growth of CdSe QDs on each nanostructured TiO_2 electrodes.Research involving Mn doped annocrystalline ZnS (ZnS : Mn) has grown in recent years, partly due to the high quantum luminescence efficiencies. We measured PA, photoluminescence (PL), and the PL excitation (PLE) spectra of surface-passivated and unpassivated ZnS : Mn. The effects of ultraviolet (UV) irradiation on the PL and PLE spectra were also studied. A decrease of PA intensity after UV exposure was observed for ZnS : Mn, indicating a decrease in the nonradiative relaxation probability. The observed increase in PL intensity indicates a corresponding increase in the radiative transition probability.

自20世纪90年代以来，利用纳米结构的TiO_2电极吸附有机染料（DSSC）在太阳能电池中的应用取得了重大进展。除了有机染料之外，半导体量子点（QD）作为DSSC中的光收集器也引起了很大的兴趣。本研究制备了不同形貌的纳米TiO_2电极。我们将CdSe量子点吸附到电极上作为光敏剂。应用光声（PA）、光电化学电流（PEC）和瞬态光栅（TG）方法进行表征。随着量子点吸附时间的增加，光致发光光谱发生红移，光电转换光谱显示量子点在可见光区的光敏化作用。不同形貌的纳米TiO_2电极上的CdSe量子点激发态电子的衰减时间不同，反映了不同形貌的纳米TiO_2电极上的CdSe量子点晶体生长的差异。近年来，Mn掺杂的非晶ZnS（ZnS：Mn）的研究越来越多，部分原因是其具有较高的量子发光效率。我们测量了表面钝化和未钝化的ZnS：Mn的PA，光致发光（PL）和PL激发（PLE）光谱。研究了紫外光照射对样品PL谱和PLE谱的影响。观察到ZnS：Mn在UV曝光后PA强度的降低，表明非辐射弛豫概率的降低。所观察到的PL强度的增加表明辐射跃迁概率相应增加。

项目成果

Study of ultrafast carrier dynamics of nanostructured TiO2 films with and without CdSe quantum dot deposition using lens-free heterodyne detection transient grating technique

• DOI: 10.1016/j.tsf.2004.11.238
• 发表时间: 2005-08
• 期刊: Thin Solid Films
• 影响因子: 2.1
• 作者: Q. Shen;K. Katayama;M. Yamaguchi;T. Sawada;T. Toyoda

T.Toyoda: "Irradiation Time Dependence of Mn-doped ZnS Nanocrystals with Oerboxylic Acid on Radiative and Non-radiative Transitions."Thin Solid Films. 438-439. 132-136 (2003)

T.Toyoda：“Mn 掺杂 ZnS 纳米晶体与羟基酸的辐照时间依赖性对辐射和非辐射跃迁的影响。”固体薄膜。

Photoacoustic and photoelectrochemical characterization of CdS-sensitized TiO_2 electrodes composed of nanotubes and nanowires

纳米管和纳米线组成的CdS敏化TiO_2电极的光声和光电化学表征

• 发表时间: 2006
• 期刊: Thin Solid Films 499
• 作者: S.Ohno;K.Nakatsuji;F.Komori;Q.Shen;A.B.Cruz;Q.Shen;L.J.Diguna;Q.Shen;Q.Shen
• 通讯作者: Q.Shen

Optical absorption, photoelectrochemical, and ultrafast carrier dynamic characterization of TiO_2 electrodes composed of nanotubes and nanowires

纳米管和纳米线组成的TiO_2电极的光吸收、光电化学和超快载流子动力学表征

• 发表时间: 2006
• 期刊: Japanese Journal of Applied Physics 45
• 作者: S.Ohno;K.Nakatsuji;F.Komori;Q.Shen;A.B.Cruz;Q.Shen;L.J.Diguna;Q.Shen;Q.Shen;Q.Shen
• 通讯作者: Q.Shen

The effect of ultraviolet irradiation on the photothermal, photoluminescence and photoluminescence excitation spectra of MN-doped ZnS nanoparticles.

紫外照射对MN掺杂ZnS纳米颗粒光热、光致发光和光致发光激发光谱的影响。

• 发表时间: 2006
• 期刊: Thin Solid Films 499
• 作者: S.Ohno;K.Nakatsuji;F.Komori;Q.Shen;A.B.Cruz;Q.Shen;L.J.Diguna;Q.Shen;Q.Shen;Q.Shen;Q.Shen;A.B.Cruz
• 通讯作者: A.B.Cruz