Nanostructured polyion complexes (PICs) are appealing in biomaterials applications. Yet, conventional assembly suffers from the weakness in scale-up and reproducibility. Only a few low-dimensional PICs are available to date. Herein we report an efficient and scalable strategy to prepare libraries of low-dimensional PICs. It involves a visible-light-mediated RAFT polymerization of ionic monomer in the presence of a polyion of the opposite charge at 5-50 % w/w total solids concentration in water at 25 °C, namely, polymerization-induced electrostatic self-assembly (PIESA). A Vesicle, multi-compartmental vesicle, and large-area unilamellar nanofilm can be achieved in water. A long nanowire and porous nanofilm can be prepared in methanol/water. An unusual unimolecular polyion complex (uPIC)-sphere-branch/network-film transition is reported. This green chemistry offers a general platform to prepare various low-dimensional PICs with high reproducibility on a commercially viable scale under eco-friendly conditions.

Analogous to cellulose, polymers whose monomer units possess both hydrogen donators and acceptors are generally insoluble in ambient water because of hydrogen bonding (HB). Herein we present stimuli-responsive long aqueous cylindrical vesicles (nanotubes) synthesized directly using HB-driven polymerization-induced self-assembly (PISA) under visible-light-mediated RAFT aqueous dispersion polymerization at 25 °C. The PISA undergoes an unprecedented film/silk-to-ribbon-to-vesicle transition and films/silks/ribbons formed at low DPs (∼25–85) of core-forming block in free-flowing aqueous solution. Pore-switchable nanotubes are synthesized by electrostatic repulsive perturbation of the HB association in anisotropic vesicular membranes via inserting minor ionized monomer units into the core-forming block. These nanotubes are synthesized at >35% solids, and tubular membranes are more sensitive than spherical counterparts in response to aqueous surroundings. This facile, robust, and general strategy paves a new avenue toward scale-up production of advanced intelligent nanomaterials.

Metal-organic frameworks (MOFs) have shown great promise in catalysis, mainly due to their high content of active centers, large internal surface areas, tunable pore size, and versatile chemical functionalities. However, it is a challenge to rationally design and construct MOFs that can serve as highly stable and reusable heterogeneous catalysts. Here two new robust 3D porous metal-cyclam-based zirconium MOFs, denoted VPI-100 (Cu) and VPI-100 (Ni), have been prepared by a modulated synthetic strategy. The frameworks are assembled by eight-connected Zr clusters and metallocyclams as organic linkers. Importantly, the cyclam core has accessible axial coordination sites for guest interactions and maintains the electronic properties exhibited by the parent cyclam ring. The VPI-100 MOFs exhibit excellent chemical stability in various organic and aqueous solvents over a wide pH range and show high CO uptake capacity (up to ∼9.83 wt% adsorption at 273 K under 1 atm). Moreover, VPI-100 MOFs demonstrate some of the highest reported catalytic activity values (turnover frequency and conversion efficiency) among Zr-based MOFs for the chemical fixation of CO with epoxides, including sterically hindered epoxides. The MOFs, which bear dual catalytic sites (Zr and Cu/Ni), enable chemistry not possible with the cyclam ligand under the same conditions and can be used as recoverable stable heterogeneous catalysts without losing performance.

The reaction of zirconium salts with meso-tetra(4carboxyphenyl)porphyrin (TCPP) in the presence of different modulators results in the formation of a diverse set of metal−organic frameworks (MOFs), each displaying distinct crystalline topologies. However, the synthesis of phase-pure crystalline frameworks remains challenging due to the concurrent formation of different polymorphs. The acidity and concentration of the modulator greatly influence the outcome of the MOF synthesis. By systematically varying these two parameters, selective framework formation can be achieved. In the present study, we aimed to elucidate the effect of modulator on the synthesis of zirconium-based TCPP MOFs. With the help of powder Xray diffraction and scanning electron microscopy, modulator candidates and the optimal synthetic conditions yielding phase-pure PCN-222, PCN-223, and MOF-525 were identified. 1 H nuclear magnetic resonance analysis, thermogravimetric analysis, and N 2 gas sorption measurements were performed on select MOFs to gain insight into the relationship between their defectivity and modulator properties.

In redox-active metal–organic frameworks (MOFs), charge transfer can occur by a redox hopping mechanism, i.e., electron hopping coupled with ion diffusion to balance electroneutrality. To elucidate the correlation between MOF structure and electron and ion diffusion, we prepared three ferrocene-doped MOF (Fc-MOF) films with different pore sizes (15–47 Å) immobilized on conductive substrates. By applying a theoretical model to the chronoamperometric responses of three Fc-MOFs, the electron and ion diffusion coefficients (D e ≈ 10–12–10–7 cm2 s–1; D i ≈ 10–16–10–12 cm2 s–1) and electron- and ion-transfer rate constants (k e‑hop ≈ 103–107 s–1; k i‑hop ≈ 10–3–101 s–1) were quantified independently. Increasing MOF pore size led to an increase in k i‑hop and a decrease in k e‑hop. The overall charge-transfer rate constant, k hop, increased when MOF pore size increased, confirming the ability to enhance charge-transfer rates through control of MOF pore size.