Effective proton conducting sites and establishing proton channels are two critical factors in developing high-performance proton exchange membranes. This study first establishes a strategy in designing effective proton conducting channels for Nafion by using solution blowing of sulfonated polyethersulfone (SPES) nanofibers containing CC3, which is an emerging porous organic cage that possesses the advantages of dissolvable organic solvents and high proton conduction from its interconnected three-dimensional pore structure. Our strategy results in SPES nanofiber networks with CC3 uniformly involved in and composite membranes with Nafion-filled interfiber voids. Benefiting from such structural features, the composite membrane exhibits high proton conductivity (0.315 S cm −1 at 80 C and 100% RH), low methanol permeability (0.69 × 10 −7 cm 2 S −1 ), excellent water absorption, thermal and dimensional stability, and single-cell performance. This study provides not only a valuable reference for the application of CC3 but also a new idea for establishment of proton transfer channels. K E Y W O R D S high proton conductivity, porous organic cage CC3, proton exchange membrane, SPES nanofibers
In the breakthrough progress made in the latest experiment (Nature (2022) 606, 507), 2D C60 polymer was exfoliated from
the quasi-hexagonal bulk crystals. Bulk C60 polymer with quasi-tetragonal phase was found to easily form 1D fullerene
structure with C60 molecules connected by C−−C. Inspired by the experiment, we investigate the strain behaviors of 1D
and 2D C60 polymers by first-principles calculations. Some physical properties of these low dimensional C60 polymers,
including structural stability, elastic behavior, band alignment and carrier mobility, are predicted. Compared with
fullerene C60 molecule, 1D and 2D C60 polymers are metastable. At absolute zero temperature, 1D C60 bears a uniaxial
tensile strain less than 11.5%, and 2D monolayer C60 withstands a biaxial tensile strain less than 7.5%. At 300 K,
ab initio molecular dynamics (AIMD) confirm that they can withstand the strains of 9% and 5%, respectively. Strain
engineering can adjust the absolute position of the band edge. In the absence of strain, carrier mobility is predicted to
be µe=398 and µh=322 cm2V−1s−1 for 1D C60 polymer, and µe,x = 74/µe,y=34 cm2V−1s−1 and µh,x = 646/µh,y=1487 cm2V−1s−1 for 2D C60 polymer. Compared with other carbon based semiconductors, these C60 polymers exhibit high effective mass, resulting in low mobility
We intend to report an interesting phenomenon related to the different interfacial transfer processes between ellipsoidal-like ZnO (E-ZnO) and rod-like ZnO (R-ZnO) nanoheterojunctions witness by the nanosecond time-resolved transient photoluminescence (NTRT-PL) spectra. Fristly, E-ZnO and R-ZnO nanoarchitectures were fabricated via facilitating the electrochemical route; and then, they decorated it with dispersed Au nanoparticles (NPs) by the methods of ion-sputtering deposition, constituting Au/E-ZnO and Au/R-ZnO Schottky-heterojunction nanocomplex, which is characterized by SEM, XRD, Raman analysis, and UV-vis absorption spectra. Steady-state photoluminescence and NTRT-PL spectra of as-fabricated Au/E-ZnO and Au/R-ZnO nanocomposites were probed for interfacial charge transfer process under 266 nm femtosecond (fs) light irradiation. Simultaneously, a distinct diversification for the NTRT-PL spectra is observed, closely associating with oxygen vacancies (Vo), which is confirmed by X-ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR) spectra. Furthermore, Au NPs act as an “annular bridge” and “transit depot” for interfacial charge transfer through local surface plasmon resonance (LSPR) effect and Schottky barrier, respectively, which is identified by NTRT-PL and time-resolved PL (TRPL) decay spectrum. Moreover, this mechanism is responsible for the enhanced photoelectrochemical (PEC) performances of methyl orange (MO) photodegradation under UV light irradiation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.