A simple synthesis protocol to prepare egg-like carbon-silica hybrids was developed where the size of a silica ball housed inside a carbon shell was tunable. An egg-tray type of carbon-silica hybrid was also made by the oxidation of egg-like carbon-silica hybrids. This oxidized hybrid has shown high ammonia adsorption capacity that is about 30 times more than the standard commercial adsorbent H-ZSM-5 (SiO₂/Al₂O₃=128).​