Fig. 2: Optimization of consecutive multimaterial printing strategy for the fabrication of biomimetic ionic hydrogel power sources (IHPS).
a Effect of different HEC and PEO contents on the apparent viscosity of the resultant HS inks. b Apparent viscosity of optimized IHPS inks at the shear rate ranging from 0.01 to 200 s−1. c Storage modulus and loss modulus as a function of the angular frequency of the optimized IHPS inks. d Effect of different inlet-outlet intersection angles on the switching interface and (e) switching length (mean ± s.d., n = 3) between two distinct inks inside the printhead. Statistical comparisons were conducted using one-way Analysis of Variance with Tukey’s tests to determine statistical significance among multiple groups. The levels of significance were established at **P < 0.01. f The photograph of the developed four-channel multimaterial printhead. g The photograph, (h) width (mean ± s.d., n = 8) and uniformity (mean ± s.d., n = 4) of consecutively-printed IHPS filaments when the air pressure varied from 80 kPa to 180 kPa while the moving speed, switching frequency, and nozzle-to-collect distance were fixed at 4.0 mm s−1, 1/4 Hz and 5.0 mm respectively. i The photograph, (j) width (mean ± s.d., n = 8) and uniformity (mean ± s.d., n = 4) of IHPS filaments when the moving speed varied from 2.0 mm s−1 to 5.0 mm s−1 while the air pressure, switching frequency, and nozzle-to-collect distance were fixed at 140 kPa, 1/4 Hz and 5.0 mm respectively. k Photograph, (l) Voc and Isc of the printed IHPS filaments with 1, 3, 5, and 10 units (mean ± s.d., n = 5). m Normalized current–voltage relations of the printed IHPS with various unit numbers connected in series or parallel. Voltage is normalized by the number of units in series, while current is normalized by the number of units in parallel. n The Nyquist plots of consecutively printed and manually assembled IHPS unit were compared. Source data are provided as a Source Data file.
