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通过测量叶绿素a苯溶液中加入溶胶-凝胶法制备的氧化锌纳米粒子后的紫外-可见吸收光谱、荧光光谱的变化,研究得出两者通过静电作用相结合,而且由于氧化锌的导带顶低于叶绿素a的第一激发态能级,所以能够产生界面电荷转移,表现在叶绿素a溶液的特征吸收峰在加入纳米粒子后峰位向长波方向移动。用355nm波长的光激发该样品得到的荧光光谱在654nm处出现一个等发射点,并且随着氧化锌量的增多叶绿素a溶液的发光被猝灭且峰位向长波方向移动,当用433nm波长的光激发时(氧化锌在此波长下没有吸收),没有等发射点但仍有猝灭和峰位移动现象,其中猝灭现象根据Stern-Volmer关系可归结为静态猝灭。另外,向离心后得到的氧化锌纳米粒子粉末中滴加叶绿素a,发现在滴加前后其红外光谱中Zn—O键的振动峰发生变化,说明氧化锌纳米颗粒与叶绿素a分子之间存在一定的相互作用,并且可能对叶绿素光合作用产生一定负面影响。
By measuring the chlorophyll a benzene solution by adding sol - gel method of zinc oxide nanoparticles after UV-visible absorption spectra, fluorescence spectra were studied by the electrostatic combination of the two, and because the conduction band of zinc oxide Top is lower than the first excited state energy level of chlorophyll a, so the interfacial charge transfer can be generated, indicating that the characteristic absorption peak of the chlorophyll a solution moves to the long wave direction after adding the nano-particles. Fluorescence spectrum of the sample excited by light of 355nm wavelength showed an emission point at 654nm, and the luminescence of chlorophyll a solution was quenched and the peak position shifted to longer wavelength with the increase of the amount of ZnO. In the case of photoexcitation (zinc oxide does not absorb at this wavelength), there is no emission but there are still quenching and peak shifting phenomena. The quenching phenomenon can be attributed to the static quenching according to the Stern-Volmer relationship. In addition, chlorophyll a was added dropwise to the zinc oxide nanoparticle powder obtained after centrifugation, and it was found that the vibrational peak of the Zn-O bond changed in the infrared spectrum before and after the dropwise addition, indicating that there was a certain level between the zinc oxide nanoparticle and the chlorophyll a molecule And may have a negative impact on chlorophyll photosynthesis.