【摘要】 研究了pH对Prof（前黄素）-MV²⁺（甲基紫精）-EDTA（乙二胺四乙酸二钠）-K₂PtCl₄,Prof-Rh（bpy）₃³⁺-TEOA（三乙醇胺）-K₂PtCl₄以及Ru（bpy）₃²⁺-Rh（bpy）₃³⁺-TEOA-K₂PtCl₄三个体系的产氢量子收率（ΦH₂）的影响。表明前一体系的最佳pH范围是4.0—5.0,后两个体系为7.5—8.1,还研究了光敏剂（PS）浓度对ΦH₂的影响,当PS浓度超过某一极限值时,ΦH₂随PS浓度增加而降低。在MV²⁺-EDTA-K₂PtCl₄催化体系中,使用吸收光谱重叠的两种光敏剂(Prof和Ru（bPy）₃²⁺一般导致ΦH₂的下降;但当其中一种PS的浓度超过极限值时,使用两种光敏剂所得的ΦH₂结果较单独使用其中任何一种要好。更多还原

【Abstract】 The irradiation of an aqueous solution containing a photosensitizer (proflavine or Ru(bpy)32+), a relay (MV2+ or Rh(bpy)32+), an electron donor (TEOA or EDTA) and a catalyst (K2PtCl4) by visible light to generate hydrogen has been studied. The hydrogen quantum yield depends not only on the nature of the photocatalytic system, but also on the experimental conditions, such as the concentration of photosensitizer, pH of the solution, the wavelength of incident light, etc.The influence of pH on the quantum yield of hydrogen photogenera tion (ΦH2) for three photocatalytic systems investigated: proflavine-MV2+-EDTA-K2PtCl4, proflavine-Rh(bpy)33+-TEOA-K2PtCl4, and Ru (bpy)32+-Rh(bpy)33+-TEOA-K2PtCl4 showed that the optimum pH values . were located in 4.0-5.0, 7.5-8.1 and 7.5-8.1 respectively.Because of the concentration quenching and excimer formation, there will be an upper limit to photosensitizer concentration. Exceeding the upper limit, ΦH2 will be lowered. Experimental results showed that the concentration limits affecting ℃H2, for different photosensitizers in a same relay/donor/catalyst system were quite different, and for the same photosensitizer in different systems, the concentration limits were also different. The difference in concentration might be more than one order of magnitude.It is interesting to note that in the MV2+-EDTA-K2PtCl4 system, by using two photosensitizers (Ru(bpy)32+ and proflavine) with superposed absorption bands, ΦH2 is generally lowered. But when the concentration of the main photosensitizer goes beyond the upper limit mentioned above, the double photosensitizer system could give better results than either single photosensitizer system.更多还原