Functionalised nanostructured carbons were obtained by template method using sucrose as carbon precursor and silica gel SG60 as structure directing agent. To introduce acid groups to carbon a different amount of phosphoric acid was added to sucrose (impregnation ratio 0-1) before filling the pores of silica gel. After carbonisation the template was removed by dissolution in HF. Carbons were characterised by SEM/EDX, nitrogen adsorption at 77 K and acid-base titration. Pore size distributions (PSD) indicated that the porous structure of carbons obtained at impregnation ratio of 0-0.75 is relatively homogeneous with mesopore mean size 3.1 nm and some microporosity. PSD significantly changes at IR= 1 showing additional larger mesopores with mean diameter of 8.2 nm. Acid-base titration showed that carbon obtained by template method without addition of phosphoric acid contains significant amount (1.75 mmol/g) of surface groups. Calculated proton affinity distributions evidence the presence of three types of surface groups that were assigned to carboxylic (pK=3.7), lactone/enol (pK= 7.6) and phenolic (pK= 10.2) groups. Addition of phosphoric acid to carbon precursor has led to 2.3-2.5 fold increase in the total amount of surface groups (up to 4.1-4.4 mmol/g). Proton affinity distribution indicates disappearance of carboxyl and lactone/enol groups and appearance of two new groups with pK= 2.2-2.4 and 6.6-6.9, which were assigned to the first and second dissociation constants of phosphate groups. It could be concluded that the functionalised nanostructured carbons can be obtained by combination of template synthesis with phosphoric acid activation.
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