The adsorption performance of ions onto the CelloZIFPaper offers further use for electrochemical sensing (Fig. ). Electrochemical measurements reveal significant changes in the current output of CelloZIFPaper upon metal adsorption (Figure ). Thus, CelloZIFPaper can be used as an electrode for metal detection. The preparation of the electrode is simple. CelloZIFPaper, prepared both with the ex-situ and the in-situ procedure 1:0.5 and 1:4 ratio (selected as a reference due to their ZIF content), were cut into rectangular-shaped pieces (1×2 cm 2 ). Then, aqueous solutions of the metal ions (Co 2+ , Cu 2+ , Fe 3+ , Cd 2+ , and Pb 2+ ) were poured dropwise on the electrodes and dried before immersing them into an electrolyte solution (Fig. ). The electrochemical measurements such as CV and LSV were conducted (Fig. ). The CelloZIFPaper electrode shows a significant shift in both current outputs, i.e., the anodic and cathodic, after the adsorption of metal ions. The adsorbed Pb 2+ ions show the most remarkable current output change, revealing high selectivity. The high selectivity of the CelloZIFPaper electrode toward Pb 2+ is mainly due to the precipitation as insoluble PbSO4. Tetrahedral metal ions such as Cu 2+ and Co 2+ ions can coordinate with Zn metal ions inside ZIF frameworks. These interactions are further supported by the potentiodynamic polarization test (PD, Figure ).