It demonstrates the use of cellulose as a more environmentally friendly alternative to replacing inorganic or synthetic polymer substrates for ZIFs (sub-class of MOFs)-based paper fabrication . We report the manufacturing of composite flat sheets consisting of ZIF-8 (or metal azolate framework-4, MAF-4) and different grades of cellulose, denoted as CelloZIFPaper, using Rapid Köthen flat sheet former. Both in-situ and ex-situ procedures are reported for the synthesis of CelloZIFPaper hybrid materials using TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)oxidized cellulose nanofibrils (TOCNF) as well as cellulose pulp (CP). The addition of CP facilitates the fabrication of flat sheets and allows the tuning of the structure of TOCNF-ZIF networks. The synthesis procedures are straightforward without needing a template or excessive harsh chemicals. They are mainly water-based and, in that respect, more environmentally friendly than other methods . The CelloZIFPapers reported herein were evaluated for the adsorption and electrochemical sensing of heavy metal ions (Fe 3+ , Cu 2+ , Pb 2+ , Co 2+ , and Cd 2+ ). In addition, this study is the first example of 'lab-on-MOF' for the electrochemical sensing of toxic metal ions.