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High-molecular-weight (e.g., 1000000 g mol −1 ) poly(ethylene oxide) (PEO) is a candidate polymer for CO 2 separation membranes because of its low cost and high CO 2 affinity. However, high-molecular-weight PEO membranes contain large crystallites, which cause structural defects. Here, we report defect-free, high-molecular-weight PEO membranes with good CO 2 separation performance prepared using amine-branched poly-(amidoamine) (PAMAM) dendrimers. PAMAM, obtained by twostep addition polymerization, acts as a filler in the all-polymer membranes. The intermolecular hydrogen bonding between the PEO and filler yields transparent, uniform membranes with improved mechanical strength. The primary amines in PAMAM facilitate CO 2 transport by increasing CO 2 solubility in the membrane. The PEO/PAMAM membranes show ∼6 times greater CO 2 /N 2 selectivity than that of neat PEO. The PEO/PAMAM membrane with 2.5 wt % PAMAM loading has a CO 2 permeability of 32.3 barrer and a CO 2 /N 2 selectivity of 42, representing the best gas separation performance of free-standing high-molecular-weight PEO-based membranes to date.

We report a one-step process for the synthesis and deposition of anatase, two-dimensional (2D), disk-shaped TiO2 (DS-TiO2) using titanium isopropoxide (TTIP), ethyl cellulose (EC), and solvents. The planar structure of EC plays a pivotal role as the sacrificing template to generate the 2D disk-shaped structure with a thickness of 1.5-3.5 μm, while a disk-like structure was well developed in the tetrahydrofuran (THF)/toluene mixed solvent. The quasi-solid-state dye-sensitized solar cells (qssDSSCs), fabricated with a nanogel electrolyte and a DS-TiO2 layer on a nanocrystalline (NC)-TiO2 photoanode, showed an energy conversion efficiency of 5.0% without any TiCl4 post-treatment, which is higher than that fabricated without DS-TiO2 (4.2%). When utilizing a poly((1-(4-ethenylphenyl)methyl)-3-butyl-imidazolium iodide) (PEBII) as the solid electrolyte, a high efficiency of 6.6% was achieved due to the combination of high mobility PEBII and a bifunctional DS-TiO2 layer with a 2D structure and anatase phase. The bifunctionality of the DS-TiO2 layer allows greater light scattering back into the device and provides additional surface area for improved dye adsorption, resulting in short circuit current density (Jsc).

A highly ionic conductive amphiphilic nanostructured polymer electrolyte with good flexibility is prepared based on a SBS-g-POEM block–graft copolymer. The performance of solid-state flexible supercapacitors based on the SBS-g-POEM electrolyte was much higher than that of the widely used conventional PVA/H3PO4 electrolyte.

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