Abstract:

Regarding the current photo-electrochemical sensor on the basis of TiO₂-carbon nano-material composite with enzyme incorporation, defects such as unfavorable environmental adaptability, undesirable anti-interference capability, inferior sensitivity, unsatisfactory substrate selectivity and insufficient efforts on the constitution-function relationship study are identified. The dependence of the interactions between the variable functional units within nano-complex and TiO₂/carbon nano-material on the structure, composition as well as physicochemical properties of the elements in nano-composite is systematically discussed. Efforts are made to define the key factor to restrict the sensing efficiency and applications of as-prepared photo-electrochemical sensor. The critical issue for the constructing the constitution-performance relationship model to develop the next generation photo-electrochemical sensor is elucidated. A classical comprehensive experiment is designed and presented. The method for preparing the electrode on the basis of nano-composite via the covalent coupling of TiO₂ nanosphere with 3D graphene oxide, and hemoglobin incorporation is introduced. The implementation of this experiment is aimed at the training of the students to use multiple techniques. Such characterization and measurement techniques can be proposed to explore the influence of the interactions between elements in nano-complex and incorporated enzyme molecules on the dynamics of relevant steps involved in the enzyme based photo-electrocatalytic reaction. The experimental set up is proposed to make the students understand and master the interrelated theory and means to determine the kinetic parameters of photo-electrocatalysis for enzyme-based electrode. The idea of closely integrating theory with practice, rigorous and realistic scientific attitude for the educational object could be developed with the execution of the comprehensive experiment.

Key words: Titanium dioxide, Carbon nano-materials, Photo-electrochemical sensor, Comprehensive experiment, Catalytic dynamics