Evaluation of polyol reduction for wet synthesis of metal nanoparticles

In this paper, experimental and theoretical attempts have been made to evaluate the reduction ability of polyols. The experimental evaluations were carried out using voltammetric measurements. In voltammetry measurements, the potential difference between polyols at higher temperature was marginal and also the measurement at boiling temperature was difficult. Thus reducing ability of polyol was evaluated assuming that it depended on the energy gap between the HOMO of polyol and LUMO of the metal ion to be reduced. The HOMO energy levels of polyols were evaluated fixing the LUMO energy level of metal. It became clear that a polyol has many conformers with different energy states and orbital energies, and the prominence of any conformer depended on their corresponding thermal energy barrier. Therefore, the reduction potential of polyol was a function of temperature and their increase was ascribed to transformation of the polyol's conformers. The theoretically estimated hierarchy of reducing ability of polyol was experimentally verified.