High-Yield Preparation and Properties of Phenolic Resin-Based Carbon Microspheres

This study aims to enhance the production efficiency of carbon microspheres (CS) and expand their potential applications. To this end, resorcinol-formaldehyde microspheres (RFS) were prepared in high yield through the modified Stöber method, utilizing resorcinol and formaldehyde as carbon sources, ammonia as a catalyst, and sodium dodecyl benzenesulfonate (SDBS) as a soft template. The resulting RFS were then carbonized to obtain high yield CS. This study examined the impact of key factors, namely, the concentration of resorcinol, ammonia, and the SDBS concentration, along with the temperature of carbonization, upon the properties of the resulting CS, which were observed with regard to microscopic morphology, average particle size, homogeneity, and yield. The findings demonstrated that the proclivity of RFS to agglomerate with one another at high carbon source concentrations was markedly diminished, while the yield of CS was notably enhanced through the introduction of the anionic surfactant SDBS. The particle size of RFS can be modified within the range 200-1000 nm by adjusting the resorcinol and ammonia concentration. The prepared RFS exhibited a regular spherical morphology and a smooth surface. Furthermore, the CS displayed a uniform spherical morphology following high-temperature carbonization, with no agglomeration or cross-linking observed between adjacent particles. It was observed that the yield of RFS reached a maximum of 93.2 g/L when the resorcinol concentration was 0.7 mol/L. Following carbonization at 800 °C, the yield of CS was found to be 41.9 g/L, with a diameter of 770 nm and good monodispersity.