Sustainable and biocompatible approaches have great concern, accordingly, green tea nanoparticles (GTNP) were synthesized and encapsulated with carboxymethyl cellulose (CMC) to prepare uniform bionanocomposite (CMC/GTNP). The structural properties of the prepared sorbents were investigated by several characterization techniques. The presence of OH, C-H, N-H, C--C and C-O-C groups in the functional structures of the 150-250 nm spherical particles without agglomeration demonstrated that modified polyphenolic materials were achieved. The polyphenolic content of green tea extract for synthesizing GTNP was determined as 34.12 +/- 0.52 mg GAE/g. Polyphenolic nanoadsorbents were utilized for CV adsorption and equilibrium adsorbent dosages were found as 8 mg (GTNP) and 6 mg (CMC/GTNP). Isotherms fitted Langmuir model and maximum adsorption capacities were 107.53 mg g- 1 for GTNP and 147.06 mg g- 1 for CMC/GTNP. The equilibrium time decreased from 150 min to 40 min by CMC incorporation. Since both adsorbent and CV molecule were positively charged, removal percentages reduced in acidic media. Adsorption rates exhibited a minor change in humic acid (HA) content and drinking water, while the anion-cation content and tap water showed a greater decrease. Weak reusabilities of adsorbents were attributed to the degeneration of active groups as a result of physicochemical reactions after each cycle. Adsorption of the samples for different dyes were explored and it was found that the affinity to cationic dyes were high, while they exhibited selectivity to CV in the presence of orange II. The proposed sorbents for CV adsorption with eco-friendly design have shown promising performances for sustainable applications.