*2.1. Materials*

Cellulose microfibrils (CMF) (~4.0 wt.%) from Cellulose Lab; trimesic acid (H3BTC), copper (II) acetate monohydrate, ethanol, and hydrochloric acid (HCl, 37%, *w*/*w*) from Sigma-Aldrich; methylene blue, ferric nitrate nonahydrate (Fe(NO3)3·9H2O), ferrous sulfate (FeSO4·7H2O), citric acid anhydrous, and sodium hydroxide (NaOH, 50%, *w*/*w*) from Fisher Scientific were used in this study. All other chemicals were of analytical grade and used without further purification.
