Stacked-layer heterostructure films of 2D thiophene nanosheets and electrochemically exfoliated graphene are constructed for ultrahigh-rate all-solid-state flexible pseudocapacitors and micro-supercapacitors with superior volumetric capacitance due to the synergetic effect of the ultrathin pseudocapacitive thiophene nanosheets and the capacitive electrochemically exfoliated graphene.

Entering a new phase: Mesogenic stoppers (purple) at the ends of the rod section of a switchable donor–acceptor [2]rotaxane induce the formation of a smectic A liquid‐crystalline (LC) phase over a wide temperature range. The bistable [2]rotaxane which contains a tetracationic cyclophane (blue), a tetrathiafulvalene unit (green), and a 1,5‐dioxynaphthalene unit (red) self‐assembles into a LC phase with a layer spacing of about 8 nm (see picture).

Two-station [2]rotaxanes in the shape of a degenerate naphthalene (NP) shuttle and a nondegenerate monopyrrolotetrathiafulvalene (MPTTF)/NP redox-controllable switch have been synthesized and characterized in solution. Their dumbbell-shaped components are composed of polyether chains interrupted along their lengths by (i) two pi-electron-rich stations-two NP moieties or a MPTTF unit and a NP moiety-with (ii) a rigid arylethynyl or butadiynyl spacer situated between the two stations and terminated by (iii) flexibly tethered hydrophobic stoppers at each end of the dumbbells. This modification was investigated as a means to simplify both molecular structure and switching function previously observed in related bistable [2]rotaxanes with flexible spacers between their stations and incorporating a cyclobis(paraquat-p-phenylene) (CBPQT4+) ring. The nondegenerate MPTTF-NP switch was isolated as near isomer-free bistable [2]rotaxane. Utilization of MPTTF removes the cis/trans isomerization that characterizes the tetrathiafulvalene (TTF) parent core structure. Furthermore, only one translational isomer is observed (> 95 < 5), surprisingly across a wide temperature range (198-323 K), meaning that the CBPQT4+ ring component resides, to all intents and purposes, predominantly on the MPTTF unit in the ground state. As a consequence of these two effects, the assignment of NMR and UV-vis data is more simplified as compared to previous donor-acceptor bistable [2]rotaxanes. This development has not only allowed for much better control over the position of the ring component in the ground state but also for control over the location of the CBPQT4+ ring during solution-state switching experiments, triggered either chemically (1H NMR) or electrochemically (cyclic voltammetry). In this instance, the use of the rigid spacer defines an unambiguous distance of 1.5 nm over which the ring moves between the MPTTF and NP units. The degenerate NP/NP [2]rotaxane was used to investigate the shuttling barrier by dynamic 1H NMR spectroscopy for the movement of the CBPQT4+ ring across the new rigid spacer. It is evident from these measurements that the rigid spacer poses a much lower barrier to the 1.0 nm movement of the CBPQT4+ ring from one station to another as compared with previous systems-a finding that is thought to be a result of the combination of fewer favorable interactions between the spacer and the CBPQT4+ ring and a relatively unimpeded path between the two NP stations. This example augers well for exploiting rigidity during the development of well-defined bistable [2]rotaxanes, which are unencumbered by the excesses of structural conformations that have characterized the first generations of molecular switches based on the donor-acceptor recognition motif.

Alternating copolymers consisting of phenyl‐capped bithiophene (red units) and oligo(ethylene glycol) hierarchically self‐assemble into nanosheets through polymer folding in some organic solvents. The lateral size of the nanosheet is controllable by temperature and concentration of the solution. The nanosheet surface can be chemically modified by using copper‐catalyzed Huisgen cycloaddition without disrupting the nanosheet structure.

Alkyl-chain-assisted self-assembled monolayers of pyridine-coordinated porphyrin rhodium chlorides were observed at the solid-liquid interface by scanning tunneling microscopy (STM). The resolved images at a molecular level were obtainable in the pure solution of pyridine-coordinated porphyrin rhodium chloride with four triacontyl groups [Rh(C300PP)(Cl)(Py)]. In the case of pyridine-coordinated porphyrin rhodium chloride with four octadecyl groups [Rh(C18OPP)(Cl)(Py)], the STM images were not obtainable in the pure solution of Rh(C18OPP)(Cl)(Py) but obtainable in the mixture containing Rh(C18OPP)(Cl)(Py) and free porphyrin C18OPP. On the basis of the mixed self-assembled monolayer analysis, the apparent difference in the adsorption free energy between Rh(CnOPP)(Cl)(Py) and CnOPP (deltaGapp) was calculated. The calculated deltaGapp values for C18OPP and C30OPP mixed systems were quite different. The disadvantage of the adsorption free energy of Rh(C18OPP)(Cl)(Py) makes it difficult to obtain molecularly resolved images of Rh(C18OPP)(Cl)(Py), and the large adsorption energy due to the long alkyl chains enabled us to obtain molecularly resolved images of Rh(C30OPP)(Cl)(Py).

A series of novel polymers, glycidyl 4‐functionalized 1,2,3‐triazole polymers (functionalized GTP) were synthesized by click functionalization of glycidyl azide polymer (GAP). Quantitative functionalization of the glycidyl polymer side groups was achieved due to the high reactivity of the azide–alkyne Huisgen cycloaddition under mild conditions. The polymers were characterized by 1H NMR, 13C NMR, IR, GPC, DLS, DSC, and TGA. We confirmed that the solubility, glass transition temperature, and decomposition temperature were controllable by changing the functional group attached at 4‐position of 1,2,3‐triazole group. Functionalized GTP expands not only the application field of GAP toward non‐explosive materials, but also the variety of poly(ethylene glycol) derivatives with different side groups.

A supramolecular organogel was prepared by mixing the glycidyl triazole polymers (GTP) functionalized with crown ether and secondary ammoniumion at the side groups. The polymers form an organogel above a concentration of 3 wt % via physical cross-links of the inclusion complex. The organogel responds to multiple stimuli, e.g., temperature, acid/base, and chemical species. The number of the effective cross-links estimated from the storage modulus and the affine network model suggests that some part of the binding sites could not work as the physical cross-links. Rheological measurement under large deformation showed that the storage modulus was constant up to 250% strain and larger than the loss modulus up to 600% strain. The high elasticity of the gel is attributable to the material design based on the high-molecular-weight flexible glycidyl polymers with many binding sites in the single polymer chain. The organogel also showed nice self-healing behavior. The molecular diffusion in the gel network was characterized by fluorescence correlation spectroscopy. Although the cross-link of the organogel has dynamic nature due to inclusion complexation, the diffusion behavior of the low-molecular-weight fluorescence tracer was similar to that observed in chemically cross-linked gels.

Side‐chain poly[2]catenanes at the click of a switch! A bistable side‐chain poly[2]catenane has been synthesized and found to form hierarchical self‐assembled hollow superstructures of nanoscale dimensions in solution. Molecular electromechanical switching (see picture) of the material is demonstrated, and the ground‐state equilibrium thermodynamics and switching kinetics are examined as the initial steps towards processible molecular‐based electronic devices and nanoelectromechanical systems.