Spray deposition of sulfonated cellulose nanofibers as electrolyte membranes in fuel cells

Abstract Nanocellulose is a promising new membrane material for fuel cells, with much lower cost and environmental impact compared Nafion or Aquivion. It mechanically strong, an excellent hydrogen barrier has reasonable proton conductivity. Here, sulfonation of cellulose nanofibers performed to enhance the conductivity (up 2 × 10 ? 3 S cm 1 ) without compromising integrity, cells are fabricated 30 µm-thick “paper” membranes. The crossover current two orders magnitude than equivalent thickness, but power density rather low. Spray-coating used deposit 8 membranes directly onto electrocatalyst layer, in process analogous 3D printing additive manufacturing. resulting paper cell high (> 0.8 A (156 mW under standard measurement conditions (H /air; 80°C; 95% RH; 0.1 MPa), attributed decreased resistance. spray-painted calculated be ~ 50 $ m , which that Nafion, even taking into consideration economies scale. This concept electrochemical energy conversion paves way mass production affordable, recyclable cells. Graphic abstract