2.3 Synthesis of RCNs
3.0g of F127 and 1.5g of glucose were dissolved in the 1.8M sulfuric acid solution, stirring for 10 h. Then, 30mL of the mixture was transferred to a 50mL Teflon-lined stainless steel autoclave for hydrothermal treatment for 30h at 140°C. After cooling to the room temperature, the products were collected by centrifugation and washed with water and ethanol several times. The obtained samples were dried at 60°C in vacuum oven overnight.