Nanodots from Palm Kernel Cake

Palm kernel cake (PKC) is the remaining of a palm ( Elaeis guineensis ) kernel after its oil is separated. Oversupply of this biomass could become an environmental problem. Meanwhile, its moist property makes it suitable for a hydrothermal carbonization to afford added values for the biomass and overcome its potential environmental problem. From the hydrothermal processes of PKC with aquadest and nanobubbled water at 200 ºC for 6 hours, nanodots with the size around 50 nm were obtained. The nanodots may be decorated with amides on their surface. Upon illumination by an ultra-violet A wave (350 nm), the nanodots emitted lights with a maximum around blue region (450 nm). No significant differences were found between the nanodots from the hydrothermal carbonizations of PKC with aquadest and the ones from the hydrothermal carbonizations of the biomass with nanobubbled water. The fluorescence property of nanodots from PKC opens up the possibility for these carbon materials to be applied in agriculture. To the best of our knowledge, this kind of research has never been reported before.