In nature, many organisms are able to accommodate a complex living environment by developing biological wet adhesive surfaces with unique functions such as fixation and predation. Significantly, most of these outstanding functions originate from the specialized micro/nanostructures and/or chemical components of these natural organisms. To design artificial surfaces with remarkable wet adhesive properties, the underlying mechanisms of the fascinating adhesion phenomena are further explored and summarized to provide continuous inspiration. Herein, a systematic overview of biological wet adhesive surfaces and the corresponding artificial counterparts from the perspective of surface micro/nanostructures is provided. First, the research progress of the typical biological wet adhesive surfaces such as the octopus, tree frogs, and mayfly larvae is introduced. Then, the fundamental models of surface adhesion in natural organisms and the commonly used instruments for measuring adhesion force are discussed. Later, the corresponding artificial wet adhesive surfaces inspired by these representative organisms are highlighted. After that, the typical methods for fabricating these surfaces are briefly introduced. Finally, future challenges and opportunities to develop bioinspired multiscaled wet adhesive surfaces with controlled adhesion are presented.

Unique membrane structures endow membranes with controlled ion transport properties in both biological and artificial systems, and they have shown broad application prospects from industrial production to biological interfaces. Herein, current advances in nanochannel‐structured membranes for manipulating ion transport are reviewed from the perspective of membrane structures. First, the controllability of ion transport through ion selectivity, ion gating, ion rectification, and ion storage is introduced. Second, nanochannel‐structured membranes are highlighted according to the nanochannel dimensions, including single‐dimensional nanochannels (i.e., 1D, 2D, and 3D) functioning by the controllable geometrical parameters of 1D nanochannels, the adjustable interlayer spacing of 2D nanochannels, and the interconnected ion diffusion pathways of 3D nanochannels, and mixed‐dimensional nanochannels (i.e., 1D/1D, 1D/2D, 1D/3D, 2D/2D, 2D/3D, and 3D/3D) tuned through asymmetric factors (e.g., components, geometric parameters, and interface properties). Then, ultrathin membranes with short ion transport distances and sandwich‐like membranes with more delicate nanochannels and combination structures are reviewed, and stimulus‐responsive nanochannels are discussed. Construction methods for nanochannel‐structured membranes are briefly introduced, and a variety of applications of these membranes are summarized. Finally, future perspectives to developing nanochannel‐structured membranes with unique structures (e.g., combinations of external macro/micro/nanostructures and the internal nanochannel arrangement) for mediating ion transport are presented.

HighlightsWe clarified the three fire boundaries of LIBs corresponding to the fire triangle Batteries are prone to ignition with forced ignition sources Batteries are hard to autoignite when temperatures are low enough LIB ignition modes can be controlled by changing temperatures and ignition sources

Morphology greatly impacts the performance improvement of conducting polymers for signal detection, actuator microfabrication, and droplet manipulation applications. However, most of the previous methods cannot satisfy practical demands due to their intrinsic drawbacks. Here, a general strategy is developed for the fabrication of patterned conducting polymers with precisely controlled microstructures (e.g., polypyrrole microsuckers) by regulating the solid/liquid/gas triphase interface and electrochemical polymerization. By regulating the distance between the Pt plate and micropillar‐structured templates, the growth directions of the microsuckers on the pillar tops change from upward (+26 ± 5°) to downward (−32 ± 7°), and their positions to the pillar tops are changed from proximal to distal due to an adjustment in the solid/liquid/gas triphase interface. The influencing factors on the microsucker growth performance, such as the time and current of electrochemical polymerization, the shape and size of micropillars, the type of conducting polymers, are systematically investigated. Furthermore, the as‐prepared microsuckers can be used for transporting water droplets because of their adjustable adhesion to water, which linearly increased from 33.5 ± 2.3 to 61.1 ± 1.2 µN with an increase in the projected epitaxial length of the microsuckers from 3.38 ± 0.39 to 8.78 ± 0.79 µm.

Patterned conducting polymer films with unique structures have promising prospects for application in various fields, such as actuation, water purification, sensing, and bioelectronics. However, their practical application is hindered because of the limitations of existing construction methods. Herein, a strategy is proposed for the superhydrophobic-substrate-assisted construction of free-standing 3D microcavity-patterned conducting polymer films (McPCPFs) at micrometer resolution. Easy-peeling and nondestructive transfer properties are achieved through electrochemical polymerization along the solid/liquid/gas triphase interface on micropillar-structured substrates. The effects of the wettability and geometrical parameters of the substrates on the construction of McPCPFs are systematically investigated in addition to the evolution of the epitaxial growth along the triphase interface at different polymerization times. The McPCPFs can be easily peeled from superhydrophobic surfaces using ethanol because of weak adhesion and nondestructively transferred to various substrates taking advantage of the capillarity. Furthermore, sensitive light-driven McPCPF locomotion on organic liquid surfaces is demonstrated. Ultimately, a facile strategy for the construction of free-standing 3D microstructure-patterned conducting polymer films is proposed, which can improve productivity and applicability of the films in different fields and expand the application scope of superwettable interfaces.