Shanghai Institute of Optics and Mechanics has made progress in the research of nanosecond laser direct writing pattern fossil graphene and its efficient solar energy interfacial evaporation

Recently, the research team of Shanghai Institute of Optics, Precision Mechanics and Research of the Chinese Academy of Sciences Soho Thin Film Optics Laboratory realized the preparation of three-dimensional porous graphene by using nanosecond laser direct writing patterns, and used its microstructure to enhance light absorption, so as to achieve effective regulation of mass transfer and heat transfer, thus promoting the evaporation of micro interfaces, Relevant research achievements were published on Advanced Materials Technologies under the title of "Nanosecond Laser Patterned Porous Graphene from Monolithic Mesoporous Carbon for High Performance Solar Thermal Interior Evolution", and were selected as the cover.

Based on the micro surface interface effect and the local thermal field regulation, the strategy of realizing the efficient utilization of low energy density solar energy and applying it to the evaporation of the solar thermal interface provides a new idea for the acquisition and efficient utilization of low-carbon clean energy. Nanoporous carbon materials have excellent broad spectrum absorption capacity and high specific surface area, and are ideal materials for solar thermal interface evaporation. However, they still face problems such as limited mass transfer, low light absorption and conversion efficiency, which make it difficult to achieve more efficient solar surface evaporation.

To solve this problem, the research team proposed and realized the direct preparation of patterned three-dimensional porous graphene on the surface of biomass formed porous carbon by nanosecond laser, and systematically studied its photothermal localized interfacial evaporation. The researchers used a new method of nanosecond laser surface scanning to sublimate carbon materials, and realized the transformation from biomass carbon to graphene at a simple, efficient and low cost, forming a new ordered porous graphene array structure. The micro nano structure of the materials was characterized by synchrotron X ray tomography. Laser treated carbon materials show higher optical absorption capacity. Patterned graphene efficiently absorbs and limits light energy to a thin surface layer, realizing optimal heat management. Porous graphene has a loose three-dimensional structure and high specific surface area, which provides a suitable path and interface for mass transfer and evaporation of water molecules, and realizes more efficient sunlight steam conversion.

This work confirmed the feasibility of convenient and efficient preparation of patterned three-dimensional graphene by nanosecond laser, and indicated the advantages and application prospects of pulsed laser preparation of patterned three-dimensional nanostructures in the preparation of materials for efficient solar photovoltaic thermal interface evaporation.

The related work has been supported by the special research assistant of the Chinese Academy of Sciences.

Fig. 1 Nanosecond laser direct writing pattern fossil graphene applied to evaporation at the photo thermal interface

Source: Shanghai Institute of Optics and Precision Machinery, Chinese Academy of Sciences