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摘要：本文采用再沉淀法制備C60納米粒子，并提出了利用光腐蝕調(diào)控C60納米粒子粒徑的方法。通過動態(tài)光散射粒徑分析、掃描電子顯微鏡、透射電子顯微鏡、紅外光譜、紫外-可見光譜等表征手段，研究了光腐蝕C60納米粒子的粒徑變化和部分機(jī)理。這些結(jié)果表明：在氧氣存在的條件下，C60納米粒子的粒徑隨著光照時間的增加而減小，其吸光度也隨著光照時間的增加而減小；在無光照或無氧條件下，C60納米粒子粒徑不發(fā)生改變，因此光照和氧氣是發(fā)生反應(yīng)的必不可少的兩個條件?；谏鲜鼋Y(jié)果和紅外光譜的分析，我們認(rèn)為C60納米粒子粒徑的改變是由于C60在光致激發(fā)下發(fā)生能量傳遞產(chǎn)生單重態(tài)氧（1O2），1O2具有較強(qiáng)的氧化性，能夠氧化C60，通過多次氧化反應(yīng)，可能破壞C60的結(jié)構(gòu)，甚至將其氧化至CO2，從而使粒徑變小。此外，本文還以三甲胺（TMA）、硫醇作為電子給體，研究了C60在光電轉(zhuǎn)換方面的應(yīng)用，結(jié)果表明在光照條件下，產(chǎn)生的C60勵起子在C60與電解液表面發(fā)生電荷分離（產(chǎn)生電子和空穴），其中產(chǎn)生的電子進(jìn)入ITO的導(dǎo)帶，而產(chǎn)生的空穴接受TMA或硫醇給出的電子，產(chǎn)生光陽極電流。同時受上述結(jié)果的啟發(fā)，以甲基藍(lán)為模型，進(jìn)一步研究了C60在光催化方面的應(yīng)用。結(jié)果表明C60在光照條件下，能夠不斷氧化甲基藍(lán)，使其逐步分解。這可能與C60作為1O2敏化劑，在光照下產(chǎn)生具有較強(qiáng)氧化能力的1O2有關(guān)；另外，根據(jù)C60光電轉(zhuǎn)換的實(shí)驗(yàn)結(jié)果，光照下產(chǎn)生的C60勵起子能夠在C60與電解液表面發(fā)生電荷分離，產(chǎn)生的空穴也可能直接氧化甲基藍(lán)。 關(guān)鍵詞：C60納米粒子；再沉淀法；光腐蝕；光電轉(zhuǎn)換；光催化
Abstract: In this research, C60 nanoparticles were first synthesized by the reprecipitation method, and we proposed a smart approach to control the size of C60 nanoparticles by photoetching. Through dynamic light scattering instrument, scanning electron microscope, transmission electron microscope, fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, etc., we studied size change of the C60 nanoparticles under light irradiation and discussed part of the mechanism of it. These results indicated that in the presence of oxygen, size of the C60 nanoparticles decreased with increasing irradiation time, and absorbance of the C60 nanoparticle suspension decreased, too; in the absence of light or oxygen, their size did not change, so light illumination and oxygen were necessary for the reaction. Based on the results above and the infrared spectrum analysis, the size change of the C60 nanoparticles was probably due to the energy transfer from photoexcited C60 to triplet oxygen and subsequently generated singlet oxygen (1O2), which had relatively strong oxidation power and could oxidize C60 or even oxidized it to CO2. In addition, we discussed the application of the C60 nanoparticles to photoelectric conversion by using trimethylamine (TMA) or thiol as electron donor. The results indicated that the photoinduced C60 exciton achieved charge separation at C60/electrolyte interface (generated electrons and holes); then the electrons were injected into conduction band of ITO, and the holes received electrons from trimethylamine or thiol; finally, the photoanodic current was generated. Inspired by the mentioned results above, we further studied the photocatalyst application of the C60 nanoparticles by photodegradation of methyl blue. The decomposition of methyl blue might relate to energy transfer generated 1O2 and/or charge separation generated holes by C60 under light irradiation. Key words： C60 nanoparticles, reprecipitation, photoetching, photoelectric conversion, photocatalysis
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