Oxidized cassava starch/polyvinyl alcohol-derived Ag-loaded carbon films with regulated structures for enhanced ethylene adsorption.

Ethylene accelerates ripening and senescence of climacteric produce, requiring efficient and regenerable adsorbents. Here, Ag-loaded carbonized composite films were prepared from oxidized cassava starch/polyvinyl alcohol/AgNO3 by electrospinning, tape casting, or freeze-drying, followed by carbonization, yielding Ag-loaded carbonization nanofiber film (CNF-Ag), Ag-loaded carbonization cast films (CCF-Ag) and Ag-loaded carbonization freeze-dried films (CFF-Ag). The forming method strongly influenced pore structure and Ag dispersion. CNF-Ag formed a porous nanofiber network with uniformly dispersed Ag nanoparticles (11 nm), the highest BET surface area, and the largest pore volume. It achieved the highest ethylene adsorption capacity of 207.1 cm3/g at 15 °C, outperforming CCF-Ag and CFF-Ag. Its average isosteric heat of adsorption was 34.9 kJ/mol, indicating strong interactions with ethylene. Cycling tests confirmed good thermal regeneration. FTIR, XPS, and DFT results showed that Ag sites dominated ethylene adsorption via π-complexation and electron transfer with the CC bond. This study highlights electrospinning as an effective strategy for constructing Ag-loaded carbon films for ethylene removal.