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将ZnO和TiO2复合形成ZnO/TiO2纳米复合材料,从而改善二者的光电转换性能成为近年的研究热点之一。总结了目前常用的ZnO/TiO2纳米复合材料的制备方法,并对每一种方法的优缺点进行了分析。阐述了ZnO和TiO2特殊形貌、暴露特殊晶面的控制制备,简单介绍了其在环境污染治理、分解水制氢等光电转换方面的应用,为今后寻找制备性能更为优异的ZnO/TiO2纳米复合光电转换材料的方法提供了参考。并提出通过对ZnO/TiO2纳米复合材料的改性、形貌和晶面控制来进一步提高材料的光电转换性能将是今后研究的重点。 相似文献
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纳米TiO_2半导体催化活性的研究进展 总被引:5,自引:1,他引:5
纳米TiO2半导体催化技术具有广阔的应用前景,近年来半导体光催化已成为功能陶瓷材料、光化学、环境保护、生物技术等领域的研究热点之一。本文简要介绍了近年来国内外纳米TiO2半导体光催化剂的研究进展,主要包括纳米TiO2光催化剂的作用机理及结构的影响;提高催化活性的方法,指出了表面贵金属沉积、复合半导体、金属离子掺杂和表面光敏化是提高催化活性和催化效率的有效途径。 相似文献
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采用水热法一步合成出TiO2单晶纳米棒有序阵列,进而制备出染料敏化太阳电池。重点探讨了退火时间变化对电池光电转化效率的影响。研究结果表明,与未退火的纳米棒组装而成的电池相比,退火后的纳米棒电池显示出更高的光电转化效率。并且当退火时间为7 min时,光电转化效率最高(5.05%),提高到未退火电池光电转化效率的300%以上。电池性能提高的原因有:TiO2纳米棒阵列与衬底间结合力的增强有利于电子传输;表面态缺陷的减少有利于抑制光生载流子的复合。结合SEM,TEM和J-V曲线等表征手段探讨了这一现象背后的物理机制。 相似文献
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Bi_2O_3/TiO_2纳米复合物的微波合成及光催化性质 总被引:2,自引:2,他引:2
以硝酸铋和硫酸钛为原料,通过直接投料微波辐射水解合成法制备了掺铋TiO2纳米复合物,并用XRD、TEM进行了表征。结果表明,直接投料摩尔比为1∶10掺铋TiO2纳米复合物,经500℃热处理后晶型为锐钛矿型,粒径为6~10nm。以催化降解甲基橙来考察其光催化活性,结果表明所制备的纳米复合物是一个好的催化剂。研究了Bi3+的掺杂量、热处理温度、催化剂用量对掺铋TiO2纳米复合物光催化性能的影响。当催化剂用量为1g/L时,2mg/L的甲基橙溶液在紫外光辐射30min后,降解率达到97%。该复合物对甲基橙溶液的光催化降解符合一级动力学方程。 相似文献
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纳米TiO_2光催化剂的改性及应用研究进展 总被引:1,自引:0,他引:1
对纳米TiO2的光催化反应机理及制备方法做了简要阐述,重点介绍了目前在纳米TiO2掺杂改性方面,尤其是非金属掺杂和共掺杂改性方面的研究进展。氮掺杂的TiO2是新发现的具有可见光催化活性的复合光催化剂,非金属掺杂可以使复合物的禁带宽度小于纯TiO2的禁带宽度,从而使TiO2的吸收边向可见光方向移动。对TiO2的N、C、S、P、卤素掺杂以及共掺杂的国内外研究现状进行了评述,分析了提高TiO2可见光催化活性的原因。对纳米TiO2光催化应用领域进行简单介绍,最后提出了在TiO2光催化剂研究中期待解决的问题及今后的发展方向。 相似文献
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以钛酸丁酯为原料,在水热过程中加入聚乙二醇(分子量2 000)合成TiO2纳米晶,并制备多孔薄膜用于染料敏化太阳能电池(DSSCs)。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、台阶仪、紫外-可见分光光度计(UV-vis)对纳米晶粒的晶体结构、薄膜的表面形貌、厚度和光学吸收性能以及电池的光电能量转换性能随聚乙二醇的加入量变化的规律进行了探索。结果表明,聚乙二醇的加入抑制了锐钛矿相TiO2晶粒的生长,诱导了金红石相的形成。当聚乙二醇的加入量为TiO2质量的5%时性能达到最佳,采用单层多孔薄膜以及不添加四-叔丁基吡啶的电解质组装的电池获得了2.86%的光电能量转换效率。 相似文献
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Cadmium sulfide (CdS) and cadmium selenide (CdSe) quantum dots (QDs) are sequentially assembled onto a nanocrystalline TiO2 film to prepare a CdS/CdSe co‐sensitized photoelectrode for QD‐sensitized solar cell application. The results show that CdS and CdSe QDs have a complementary effect in the light harvest and the performance of a QDs co‐sensitized solar cell is strongly dependent on the order of CdS and CdSe respected to the TiO2. In the cascade structure of TiO2/CdS/CdSe electrode, the re‐organization of energy levels between CdS and CdSe forms a stepwise structure of band‐edge levels which is advantageous to the electron injection and hole‐recovery of CdS and CdSe QDs. An energy conversion efficiency of 4.22% is achieved using a TiO2/CdS/CdSe/ZnS electrode, under the illumination of one sun (AM1.5,100 mW cm?2). This efficiency is relatively higher than other QD‐sensitized solar cells previously reported in the literature. 相似文献
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Thioglycolic acid (TGA) capped cadmium selenide (CdSe) nanoparticles were synthesised in aqueous medium through wet chemical method using sodium selenite as the selenium source. The synthesised particles were transformed into organic medium using 1-dodecanethiol through efficient partial ligand exchange strategy. The UV–visible spectra recorded for the particles reveal the size distribution in water as well as in organic solvent. TEM analysis of the synthesised particles shows the size and the nature of distribution of the particles in solution. The phase transferred particles were blended with the polymer poly-3-hexyl thiophene (P3HT) in chloroform. UV–visible and photoluminescence spectra of the polymer with various volumes of the nanoparticles clearly indicate the effective coupling and the efficient charge transfer process in the blend. SEM analysis of the CdSe–P3HT blends confirms the effective distribution of the nanoparticles in the polymeric matrix. AFM studies reveal the morphology of the nanoparticles and the phase separation process in the blends. 相似文献
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ZnSe是一种很有应用前景的半导体光电材料,得到了广泛的关注,制备高质量的ZnSe已成为光电 技术领域重要的研究课题之一.本文详细叙述了近年来ZnSe的各种制备技术的研究进展及其特点. 相似文献
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TiO2纳米管阵列对染料敏化太阳能电池性能的影响 总被引:1,自引:0,他引:1
通过恒压阳极氧化法在Ti箔表面制备了结构规整的TiO2纳米管阵列,研究了氧化时间和退火温度对纳米管阵列的尺寸和晶体结构的影响。用制得的纳米管阵列电极组装了染料敏化太阳能电池(DSSC),研究了纳米管长度、退火温度和电极面积对DSSC光电性能的影响。结果表明,纳米管管径和壁厚均与氧化时间无关,而纳米管长度则随着氧化时间延长而增加。在450℃及更低温度退火时,纳米管中只出现锐钛矿相;而在500℃退火时,纳米管中则又出现了金红石相。由厚度为27μm、退火温度为450℃的纳米管阵列电极组装成的DSCC具有最佳的光电转化性能。DSCC的光电转化效率随电极面积的增加而降低。 相似文献
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Significant increases in the solar conversion performance of thin film CdS/CdTe solar cells have been realized in recent years by the inclusion of wider gap materials, notably CdS:O, in place of the CdS window layer. Similarly, use of CdSe in combination with CdTe has given yet further increases in current density due to the formation of CdTe1-xSex and the resulting enhanced long wavelength collection. Here we report the synthesis and properties of oxygenated CdSe films and their influence on device performance when included into CdTe solar cells. The CdSe:O films were made by pulsed laser deposition in oxygen at pressures of 0.01 and 0.03 Pa. Optical transmission measurements indicated that oxygenation acts to increase transparency in the 400–750 nm range, and that increased oxygen content acts to increase the apparent absorption threshold slightly. The higher transmission acts to increase the spectral response of CdTe solar cells in the range 350–500 nm compared to CdSe- and CdS-containing control devices. Moreover, the already known advantage of enhanced long wavelength response (850–910 nm) over that of CdS/CdTe is retained for both CdSe and CdSe:O window layers. Hence the use of CdSe:O as a window layer is demonstrated to increase the current harvesting of these solar cells by increasing both their long and short wavelength performances. These gains in the short circuit current outweigh small losses in fill factor and open circuit voltage making CdSe:O a valuable possible means to increase the performance of CdTe solar cells. 相似文献
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Yuanhao Wang Hongxing Yang Yong Liu Hai Wang Hui Shen Jin Yan Hongmei Xu 《Progress in Photovoltaics: Research and Applications》2010,18(4):285-290
This paper reports a simple and facile method for directly growing self‐organized TiO2 nanotubular arrays around the whole Ti mesh by electrochemical anodization in organic electrolytes and their application in all‐Ti dye‐sensitized solar cells (DSSCs). Compared with the traditional fluorine‐doped tin oxide (FTO)‐based DSSC and the backside illuminated DSSC, this type of DSSC showed advantages such as low resistance, cheap fabrication cost and enhanced sunlight utilization. Different thicknesses of nanotubular array layers were investigated to find their influence on the photovoltaic parameters of the cell. We also considered three types of meshes as the substrates of anodes and found that the cell with 6 openings/mm2 exhibited the highest conversion efficiency of 5.3%. The area of the cell had only a little impact on the photovoltaic performances. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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采用溶胶-凝胶结合氢气还原方法,制备了Fe与TiO2两相共存的纳米复合物。透射电子显微镜(TEM)图片显示,纳米复合物的颗粒大小为100~300nm,且具有明显的核/壳结构。X射线衍射结果表明,纳米复合物中存在a-Fe与金红石型TiO2结构,未发现其他杂相。振动样品磁强计(VSM)的测量结果表明,样品具有较高的比饱和磁化强度。研究表明,通过控制前驱物的用量,能有效改变样品的磁性。热重分析(TGA)结果表明,样品具备很好的抗氧化性。复合介电谱和磁谱表明,在测量的微波频率范围内,样品的介电损耗大于磁损耗。 相似文献