Composite of PZT (lead zirconate titanate) and PLZT (lead lanthanum zirconate titanate) along an organic, renewable, conductive, and flexible matrix have been developed. The conductive paper was obtained through the reaction between the cellulose extracted from banana stem and functionalized MWCNT. This reaction was made in the presence of hydrogen (from H2SO4), which reduced the size of the cellulose by acid hydrolysis and promotes the interaction between its hydroxyls and the carboxyl groups of nanotubes. Afterward, the PZT particles were synthesized and grown up on the conductive paper by microwaves-assisted hydrothermal synthesis (MHS). The composite material was characterized by structure and morphology. Moreover, gas-sensing in the presence of methanol and electrical resistance as a function of temperature were also investigated. In this way, a simple, low-cost and successful synthesis was reported. Also, a promising flexible was obtained using a chemical transformation process from banana residue as source of cellulose.