Utilization of mesoporous phosphotungstic acid in nanocellulose membranes for direct methanol fuel cells.

Nanocellulose (NC) composite membranes containing novel ternary materials including NC, imidazole (Im), and mesoporous phosphotungstic acid ( m -PTA) were successfully fabricated by a phase inversion method. The single-particle size of NC was 88.79 nm with a spherical form. A m -PTA filler with a mesopore size of 4.89 nm was also successfully synthesized by a self-assembly method. Moreover, the fabricated membrane NC/Im/ m -PTA-5 exhibited the best performances towards its proton conductivity and methanol permeability at 31.88 mS cm -1 and 1.74 × 10 -6 cm 2 s -1 , respectively. The membrane selectivity was 1.83 × 10 4 S cm -3 .