Materials involving nanoconfinement of ionic liquids (ILs) have been pursued for functionalities and ionic devices. However, their complex synthesis, challenges to achieve long-range order, and laborious tunability limit their practical implementation. Herein, these challenges are addressed by complexing surfactants to ILs, yielding a facile, modular, and scalable approach. Based on structural screening, ionic complexation of di-n-nonylamine to the terminal sulfonic acid of 1-(4-sulfobutyl)-3-methylimidazolium hydrogen sulfate IL is selected as a proof of concept. Spontaneous homeotropic smectic order over micrometers is observed, with alternating ionic and alkyl layers. The 1 nm thick ionic layers involve 2D crystalline internal order up to 150 °C, strongly promoting anisotropic ion transport (σ || /σ ⊥ > 6500), and curiously, still allowing fluidity. High ionic conductivity of 35 mS cm −1 and mesoscopic diffusion coefficient of ≈10 −5 cm 2 s −1 at 150 °C along the ionic layers are observed. Fast anisotropic ion transport by simply complexing two components open doors to functional materials and applications.

Electrically driven dissipative gradients of superparamagnetic nanoparticles allow voltage-controlled magnetism and patterns.

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Hierarchical self-assemblies suggest routes for emerging structural complexities of soft matter towards multifunctional behaviors, however, involving challenges to design the balanced competing attractive and repulsive interactions required for the different length scales. Herein, self-assembly of zwitterionic amphiphiles were explored in the solvent-free state, where especially bis-n-tetradecylphosphobetaine shows temperature-driven reversible transition from low-temperature molecular-scale self-assemblies to high-temperature hierarchical self-assembly, combining colloidal and molecular order. The colloidal order results from layered molecular packing to 2D-nanoplatelets, which form well-defined oblique self-assemblies in several nanometer periodicity, allowing viscous fluidity upon shearing. The colloidal-scale structure emerges due to packing frustration between the tightly packed zwitterionic moieties and alkyl chains, and can be relieved by plasticizing with ionic liquids for purely smectic-A liquid crystallinity. Thus, even molecules with seemingly simple chemical structure can lead to structural hierarchy and tunable complexity by balancing the competing long-range electrostatics and short-range nanosegregations.