Fig. 2

(a) XRD pattern of the original oval-like cobaltic MOF; (b) XRD pattern of HOCO; (c) FTIR profiles of the pristine oval-like Co-MOF and HOCO; (d) long-range Raman spectroscopies of Co₃O₄ NP and HOCO; (e) and (f) Raman spectroscopies at specific regions