Bioinspired Photo-Responsive Liquid Gating Membrane

Abstract

Stomata in the plant leaves are channels for gas exchange between the plants and the atmosphere. The gas exchange rate can be regulated by adjusting the opening and closing of stoma under the external stimuli, which plays a vital role in plant survival. Under visible light irradiation, the stomata open for gas exchange with the surroundings, while under intense UV light irradiation, the stomata close to prevent the moisture loss of plants from excessive transpiration. Inspired by this stomatal self-protection behavior, we have constructed a bioinspired photo-responsive liquid gating membrane (BPRLGM) through infusing the photo-responsive gating liquid obtained by dissolving the azobenzene-based photo-responsive surfactant molecules (AzoC8F15) in N,N-Dimethylacetamide (DMAC) into nylon porous substrate, which can reversibly switch the open/closed states under different photo-stimuli. Theoretical analysis and experimental data have demonstrated that the reversible photoisomerization of azobenzene-based surfactant molecules induces a change in surface tension of the photo-responsive gating liquid, which eventually results in the reversible variation of substantial critical pressure for gas through BPRLGM under alternating UV (PCritical (off)) and visible (PCritical (on)) light irradiations. Therefore, driven by a pressure difference ΔP between PCritical (on) and PCritical (off), the reversible switches on the open/closed states of this photo-responsive liquid gating membrane can be realized under photo-stimuli. This bioinspired membrane with switchable open/closed liquid gating performance under photo-stimuli has the opportunity to be used in the precise and contactless control of microfluidics.

Self-Oscillating Liquid Gating Membranes with Periodic Gas Transport

“…Therefore, the pores can be reversibly sealed in a closed state and rapidly reconfigured under pressure-driven to generate an open state and liquid-lined pathway. The system shows a flexible and stable switching performance, which breaks through the limitations of traditional solid membrane materials in gas transport control [ 13 , 14 , 15 , 16 ].…”

Fluid manipulationviamultifunctional lubricant infused slippery surfaces: principle, design and applications

“…28 (d) The bioinspired photo-responsive gating membrane of BPRLGM. 130 (e) Schematics of liquid gating magnetoelastic porous membrane and self-driven liquid release. 27 In addition, the SLIPS, as a surface capable of generating electricity by water droplets, shows a good prospect for sustainable energy production.…”

“…This material can be reversibly switched between closed and open states under different photo stimuli. 130 Liu et al introduced the magnetic response into the liquid-based gating mechanism and designed a new system based on a liquid-gated magnetoelastic porous membrane with reversible meniscus-shaped deformation. 27 The advantage of this magneto responsive self-driven system is that it provides a general and convenient method for achieving active regulation of gas-liquid release.…”

“…(c) Illustration of the switchable mechanism of the CO 2 -CRSV 28. (d) The bioinspired photo-responsive gating membrane of BPRLGM 130. (e) Schematics of liquid gating magnetoelastic porous membrane and self-driven liquid release 27.…”

Non-Newtonian fluid gating membranes with acoustically responsive and self-protective gas transport control

“…Controlled gas release plays an important role in many fields, such as gas valves, 5,42 gas-related chemical reactions, 43,44 flexible actuators and robotics, 45,46 and biomedicine. 47–50 In this section, we propose a pressure-imposed strategy to achieve remote gas release regulation via acoustic modulation and explore the self-protective behaviour of the gating system during the instant gas invasion.…”