Exploring the influence of solar pyrolysis operation parameters on characteristics of carbon materials

Carbon materials can be produced by different methods, one of them is solar pyrolysis, which is attaining renewed interest due to simplicity to transform biomass with environmental advantages. However, pyrolysis operation parameters are decisive factors that determine the morphological and chemical properties of carbon. This work aims to study the influence of temperature and heating rate of solar pyrolysis in the properties of carbon. Pyrolysis experiments were carried out in the 25 kW IER-UNAM solar furnace. Agave biomass was processed in a glass spherical solar reactor. Temperatures between 500 and 900 degrees C were utilized, as well as heating ramps between 4 and 30 degrees C/min. Samples were analyzed with several techniques. The results of the experiments indicate that solar pyrolysis temperature and heating rate scarcely impact the carbon composition, however the structure, surface area and electrochemical response are highly affected by both. The control of the operation conditions allows to produce carbon materials that exhibit promising properties to be used as catalyst supports for polymer electrolyte membrane fuel cells and electrolyzer cells applications. Therefore the use of concentrated solar energy represents an attractive method to obtain these valuable materials.