Self-folding microscale origami patterns are demonstrated in polymer films with control over mountain/valley assignments and fold angles using trilayers of photo-crosslinkable copolymers with a temperature-sensitive hydrogel as the middle layer. The characteristic size scale of the folds W = 30 μm and figure of merit A/ W (2) ≈ 5000, demonstrated here represent substantial advances in the fabrication of self-folding origami.

A hydrogel–dielectric‐elastomer system, polyacrylamide and poly(dimethylsiloxane) (PDMS), is adapted for extrusion printing for integrated device fabrication. A lithium‐chloride‐containing hydrogel printing ink is developed and printed onto treated PDMS with no visible signs of delamination and geometrically scaling resistance under moderate uniaxial tension and fatigue. A variety of designs are demonstrated, including a resistive strain gauge and an ionic cable.

Zinc‐based batteries are potential candidates for flexible energy storage due to their high capacity, low cost, and intrinsic safety. Hydrogel electrolytes with saturated aqueous solvents can provide remarkable electrochemical performance while retaining satisfactory flexibility for zinc‐based batteries. The past decades have witnessed their fast growth. However, the study of zinc‐based batteries with hydrogel electrolytes under extreme conditions is still in the early stages and many technical issues remain to be addressed. In this review, the physical and chemical properties of hydrogel electrolytes are discussed for application in zinc‐based batteries. Strategies towards hydrogel electrolytes and flexible zinc‐based batteries under extremely high/low temperatures or under deformation conditions and their behaviors are reviewed and analyzed. Moreover, design strategies for all‐around hydrogel electrolyte that are appropriate for use in all these extreme conditions are proposed. A perspective discussing the challenges and future directions of hydrogel electrolyte for zinc‐based batteries is also provided.

Hybrid spherical and wormlike amphiphilic block copolymer micelles are formed through evaporation-induced interfacial instabilities of emulsion droplets, allowing the incorporation of pre-synthesized hydrophobic inorganic nanoparticles within the micelle cores, as well as co-encapsulation of different nanoparticles. This encapsulation behavior is largely insensitive to particle surface chemistry, shape, and size, thus providing a versatile route to fabricate multifunctional micelles.

Shape programmable materials capable of morphing from a flat sheet into controlled three dimensional (3D) shapes offer promise in diverse areas including soft robotics, tunable optics, and bio-engineering. We describe a simple method of 'grayscale gel lithography' that relies on a digital micromirror array device (DMD) to control the dose of ultraviolet (UV) light, and therefore the extent of swelling of a photocrosslinkable poly(N-isopropyl acrylamide) (PNIPAm) copolymer film, with micrometer-scale spatial resolution. This approach allows for effectively smooth profiles of swelling to be prescribed, enabling the preparation of buckled 3D shapes with programmed Gaussian curvature.