凯发

Ultraviolet (UV) photochemical oxidation has recently intrigued more and more attention on modifying graphene electrical optical properties as a unique dry disposal technique. In this process, a traditional low pressure mercury lamp composed of two major lines at 184.9 nm 253.7 nm can decompose oxygen molecules by forming a mixture of strong oxidizing radicals and ozone molecules which subsequently react with carbon atoms. In this presentation, I will first briefly analyze status, applications and limitations of the nowadays commercial UV photochemical technique used in the graphene field. Then I will introduce our newly developed vacuum UV photochemical oxidation machines that can precisely control photochemical reaction process, as well as provide easy integration with other techniques like in-situ electrical property measurement. We finally discuss our new progress photonic and optoelectronic fields via utilizing our vacuum UV oxidation technique. For microcleaved few-layer graphene flakes, wide band photoluminescent graphene nanostructures and quantum dots in the visible region can be obtained successfully by adjusting the photochemical oxidation parameters. Besides, the chemical vapor deposition (CVD) grown and transferred large area graphene film can be effectively cleaned and electrically improved by increasing its conductivity after proper UV oxidation. Inspiringly, this vacuum UV oxidation technique is applicable for modification of the popularly used graphene powder. Our developed vacuum UV photochemical oxidation technique presents to be clean, easy-control and repeatable for efficient graphene modification, and it might play a vital role in propelling graphene industrialization in various fields. 

Reference:

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