Two CoAPO materials (CoAPO-34 and CoAPO-20) with relatively high Co2+/Al3+ substitution level were synthesised in either fluoride-free or fluoride-containing reaction mixture using piperidine as a structure-directing agent. Present investigation established that fluoride ions acted only as a mineralising agent and did not impart any structure-directing role. TG-DTG-DSCcurves differ considerably for CoAPO-34 and CoAPQ-20, thus indicating that thermal decomposition of piperidine proceeds in a different manner for these products.