Fig. 3: Design principle of the architected lattice.
From: A bioinspired surface tension-driven route toward programmed cellular ceramics
a Schematic diagram of the liquid capture. Precursor solution (fluid 1) is captured inside a solid frame (solid 3) in air (fluid 2), where a is the frame length, r is the frame radius, k is the central angle corresponding to the interface arc of fluid 1 and solid 3, θ123 is the contact angle of the interface among fluid 1, fluid 2, and solid 3, and S12, S13, and S23 are the interface area of fluid 1 and fluid 2, fluid 1 and solid 3, and fluid 2 and solid 3, respectively. b The variation of contact angle along with the concentration. Error bars are standard deviation and include 6 independent measurements for each composition. Insets show the illustration and optical image of the contact angle among fluid 1, fluid 2, and solid 3, where σ23, σ12, σ13 are the interfacial tension of fluid 2-solid 3, fluid 1-fluid 2 and fluid 1-solid 3 respectively. c FE results of the dependence of α on the contact angle θ123 for precursor solution in air, where α is the ratio of S13 to S3 and S3 is the surface area of solid frame. Insets show the liquid distribution at the contact angle of 20° and 60°. d Theoretical and experimental results showing the influence of frame length a and radius r on the liquid capture. The blue and yellow regions respectively include the appropriate geometry parameters for successful liquid capture in unit cell and liquid arrangement in architected lattice from theoretical analysis. The red circle and blue cross icons indicate successful and failed liquid capture in the experiments, respectively. Inset shows the optical image of the experimental results (black dash line) with various frame lengths from 0.4 mm to 2.2 mm and the same radius of 0.1 mm. e The equilibrium point (star icons) shifts with the variation of frame radius (0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm). Inset shows the optical image of the experimental results. Scale bar, 5 mm. f Calculated results of the liquid height dependent on the frame radius, agreeing well with the experimental results. Error bars are standard deviation and include 5 independent measurements for each radius. g Optical image of the architected lattices with precursor solution filled in a programmed arrangement. The length of the unit cell is a, and the interval lengths are (i) 2a, (ii) 3a, and (iii) 4a, respectively. Scale bar, 5 mm. h Finite element analysis of the formation of the programmed liquid arrangement from (i) to (iv) under gravity for the architected lattice with an interval length of 3a.
