Solvothermal syntheses of hollow carbon microspheres modified with -NH ₂ and -OH groups in one-step process

Homogeneous and monodisperse hollow carbon microspheres (HCMS) functionalized with amino and hydroxyl groups are synthesized by decomposing 2,4,6-tribromophenol/ferrocene mixture in the presence of ammonia via a one-step solvothermal process at 250 °C for 24 h. The effect of experimental conditions on the morphology of carbon microspheres has been investigated systematically. The surface of the HCMS is modified with amino and hydroxyl groups through the synthesis process as confirmed by infra-red spectroscopy and X-ray photoelectron spectroscopy. The pore-size distribution and the specific area of macropores are measured by nitrogen adsorption-desorption and mercury intrusion porosimetry. The as-synthesized HCMS has the high Brunauer-Emmett- Teller surface area of 289m²/g and macropores whose diameter is mostly larger than 100 nm. To investigate the chemical reactivity of functionalized groups on the surface of HCMS, Au and Ag nanoparticles are successfully loaded onto HCMS by direct reduction of HAuCl₄ or AgNO₃ without adding any reducing agent.