Block copolymer nanoparticles have been widely used for advanced materials. However, the stabilization is challenging. Herein, we present a method for convenient yet reliable synthesis of stabilized polyion complex (PIC) nanometer-sized spheres and micrometer-sized ultrathin lamellae and vesicles by taking advantage of the wavelength orthogonality of UV-induced disulfide exchange and visible light-initiated polymerization-induced electrostatic self-assembly (PIESA). Disulfide-containing PIC vesicles are synthesized at scale using this PIESA, undergoing a small sphere-to-larger sphere-tolamella-to-vesicle transition. As such, surface-neutralized and surface-charged micrometer-sized vesicles can be achieved. UV irradiation of the vesicles (5.0 mg/mL in water) in ambient air induces very fast exchange reaction of locally confined/enriched disulfide motifs, leading to cross-linking, shape transition, and cystamine salt release in 4 min. As such, cross-linked PIC spheres, lamellae, and vesicles can be achieved, in one pot, from one single vesicle precursor. The wavelength orthogonality is evident from disabled PIESA synthesis under UV light and ineffective postpolymerization functionalization under visible light. The cross-linked PIC spheres and micrometer-sized ultrathin lamellae and vesicles show outstanding shape/size stability and high reversibility in the solution-adaptive electrostatic hierarchical self-assembly and disassembly upon adding ethanol into aqueous dispersion and subsequent dialysis.

We report an updated polymerization-induced thermal self-assembly (PITSA) [Figg, C. A.; et al. Chem. Sci. 2015, 6, 1230]. The concept is validated using visible light initiated RAFT aqueous dispersion polymerization of diacetone acrylamide monomer at 25 – 70 °C. This PITSA formulation produces block copolymer lamellae at 25 °C while the copolymer morphology evolves from spheres to worms to vesicles during polymerization at 60 °C, which is above the lower critical solution chain length (LCSCL) of the core-forming block. Particle shape and size uniformity can be controlled by reaction temperature using a single photo-PISA formulation. Vesicles-to-lamellae and vesicles-to-worms transitions are achieved in situ upon cooling reaction dispersions (70 °C) to 25 °C, leading to the transformation of initially free-flowing liquids to physical hydrogels. Moreover, reversible thermoresponsive lamellae-to-vesicles-to-lamellae and worms-to-vesicles-to-worms transitions of as-synthesized nanoparticles are achieved in dilution in a heating–cooling cycle. This thermoresponsive photo-PISA formulation updates Figg’s PITSA protocol mainly in three aspects: (1) the absence of LCST limitation, (2) user-friendly control of particle shape and size uniformity by reaction temperature using a single photo-PISA formulation, and (3) reversible thermoresponsive transition of the ketone-functionalized vesicles to customer-guided lamellae or worms.

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Different metal−organic units were introduced into the {PMo 12 } polyoxometalate (POM) system to yield three porous coordination polymers with distinct characteristics, {Cu(pra) 2 } [{Cu-(pra) 2 } 3 {PMo 11 VI Mo V O 40 }] (1), [{Ag 5 (pz) 6 (H 2 O) 0.5 Cl}{PMo 11 VI Mo V O 40 }] (2), and [{Cu 3 (bpz) 5 (H 2 O)}{PMo 12 O 40 }](3) (pra = pyrazole; pz = pyrazine; bpz = benzopyrazine), via an in situ hydrothermal method. In comparison with the maternal Keggin cluster and most reported POM electrode materials, compounds 1−3 exhibit larger specific capacitances (672.2, 782.1, and 765.2 F g −1 at a current density of 2.4 A g −1 , respectively), superior cyclic stability (91.5%, 89.3%, and 87.8% of cycle efficiency after 5000 cycles, respectively), and boosted conductivity, which may be attributed to the introduction of metal−organic units. The result indicates that metal−organic units can effectively enhance the capacitance performance of POMs. This may be due to the fact that they provide additional redox centers, induce the formation of stable porous structures, and improve ion/electron transfer efficiency. Compounds 1−3 present excellent electrocatalytic activity in reducing peroxide (H 2 O 2 ) and oxidizing ascorbic acid (AA). In addition, compound 2 shows an outstanding sensing performance detection of AA and H 2 O 2 .

{P6Mo18} poly­(oxometalate) (POM) clusters have huge steric hindrance and limited active oxygen atoms, which make them difficult to combine with metal–organic units to form three-dimensional (3D) porous structures. Therefore, functionalization of such POMs has always been a bottleneck that is difficult to break through. In this study, {P6Mo18} POM was successfully grafted on a lock-like metal–organic chain to generate a multiporous coordination polymer, [{Na­(H2O)­(H2btb)}­{Cu4 I(H2O)­(pz)5Cl}­{H2Sr⊂P6Mo2 VMo16 VIO73}]·3H2O (1) (pz = pyrazine; btb = 1,4-bis­(1,2,4-triazole) butane). Meanwhile, a zero-dimensional (0-D) control compound with only btb ligands as counterions, (H4btb)­[H4Sr⊂P6Mo2 VMo16 VIO73]·3H2O (2), was also obtained via a hydrothermal reaction. Compound 1 represents the first basket-type 3D poly­(oxometalate) metal–organic framework (POMOF) assembly, which possesses interpenetrating pores and complex topology. 1-GO-CPE displays improved supercapacitor (SC) performance (the specific capacitance of 929.4 F g–1 at a current density of 3 A g–1 with 94.1% of cycle efficiency after 5000 cycles) compared with 2-GO-CPE and most reported POMOF electrode materials, which may be due to the outstanding redox capability of basket-POM, introduction of metal–organic chains, intersecting pores, and excellent conductivity of graphene. An asymmetric SC device with 1-GO-CPE as the negative electrode exhibits an energy density of 29.7 Wh kg–1 with a power density of 3148.2 W kg–1 and long-lasting cycling life. In addition, 1-GO-GCE as an electrochemical sensor responds to dopamine (DA) at a voltage of 0.40 V and shows lower detection limits (0.19 μM (signal-to-noise ratio (SNR) = 3)), higher selectivity, and good reproducibility in the linear range of 0.56 μM to 0.24 mM. The ability to accurately detect the content of DA in biological samples further proves the feasibility of the sensor in practical applications.