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The efficiency of the electrochemical performance of the separator in supercapacitors (SCs) is primarily determined by the ion transport performance, which in turn depends on the pore size uniformity and electrolyte absorption. Cellulose separators with high electrolyte absorption are expected to exhibit outstanding ion transport; however, they remain largely unexplored. Here, we report the fabrication of cellulose separators that feature a hierarchically cross-linked network, and tightly stacked structures can achieve extremely low separator resistivity and enhanced ion transport properties. Compared with common separators, this work enables the investigation of ionic transport in greater detail. High electrolyte absorptivity is realized due to its uniform pore environment, high pore density, hydrophilicity, ultrathin thickness, and reduced impedance, which guarantees the excellent ion transport performance of the separator. The high thermal stability of regenerated cellulose enables the separator to preserve its structural integrity at temperatures as high as 200 °C, thereby ensuring the safety of supercapacitors. This work opens up the application of an ultrathin regenerated cellulose separator with enhanced ion transport performance in large-scale industrialized production with implications that can promote the development of safe and high-performance separators. [ABSTRACT FROM AUTHOR]

Salinity gradient cells are widely used in power generation from gradient concentration solutions of one electrolyte. High ionic flux sub‐micro channels membrane can offer a high current density for salinity gradient power generation with a significant power output. Herein, based on numerical simulation model with Poisson‐Nernst‐Planck‐Navier‐Stokes (PNP‐NS) equations, a high ionic flux sub‐micro channel model with assumption is introduced that measured current is contributed by Cl− ionic flux across the membrane. An ion channel system is built for experiment, in which a glass membrane with regular symmetric sub‐micro cylindrical channels and high effective channel area is applied, ion conductance and salinity gradient energy conversion property are tested. This PNP‐NS equations model simulation fits experiment well, its mechanism is also studied by the model. In addition, by mixing artificial sea water (0.5 m NaCl) and river water (0.01 mm NaCl), the output power density of this 50‐fold salinity gradient system can achieve 4.16 W m−2, and the highest output power density will be up to 7.91 W m−2 under a 0.5 m/0.001 m 500‐fold salinity gradient. This high ionic flux membrane shows a good performance for practical application in salinity gradient power generation. [ABSTRACT FROM AUTHOR]

The aim of this study is to realize the controlled construction and modulation of micro-/nanostructures of conductive composite materials (CCMs) in a facile way. Herein, interdigital electrodes are prepared by direct-ink-write printing co-blended inks made of ethyl cellulose and carbon nanotubes on cellulose paper. The cellulose nanofibers (CFs) are prepared by electrospinning cellulose acetate on to an aluminum foil, followed by deacetylation in NaOH/ethanol. All co-blended inks exhibit a typical non-Newtonian shear thinning behavior, enabling smooth extrusion and printing. The above electrodes and the conductive CF films with excellent thermal stability are assembled into a pressure sensor, which has a high sensitivity (0.0584 KPa−1) to detect the change in external loading pressure. The obtained porous CFs film is further endowed with conductivity by in situ polymerization of polypyrrole (PPy), which are uniformly distributed on the CFs surface as particles; a triboelectric nanogenerator is constructed by using the CF@PPy film as a tribo-positive friction layer to achieve efficient energy harvesting (output voltage = 29.78 V, output current = 2.12 μA). Therefore, the construction of CCMs with micro-/nanostructures based on cellulose derivatives have essential application prospects in emerging high-tech fields, such as green electronics for sensing and energy harvesting. [ABSTRACT FROM AUTHOR]

As over exposure of the earth to ultraviolet (UV) light and increased amount of petroleum-based plastic waste, biodegradable UV-blocking materials are desired for diverse sustainable applications. The corncob residue from xylitol production (CRXP), as a kind of lignocellulosic waste, is mainly composed of cellulose and lignin. Here, we developed a series of CRXP films through a top-down approach (i.e., tunable delignification and regeneration) without any additional additives. Regenerated films, prepared from treated CRXP with lignin contents of 4.4%–29.7%, had excellent UV-blocking capability: 68.6–99.2% for UVB (290–320 nm) and 47.1–98.2% for UVA (320–400 nm). Moreover, these films showed high optical transparency (50.6–86.6%), enhanced water vapor barrier property (2.17–2.76 × 10–11 g cm cm−2 s−1 mmHg−1), great surface hydrophobicity (water contact angle = 73.3°–86.6°), and good thermal stability. Overall, our sustainable UV-blocking films based on CRXP have potential applications in the fields of electronics, food packaging, windshields, and so forth. This study provides new insights into converting lignocellulosic waste directly to high value-added functional bioproducts. [ABSTRACT FROM AUTHOR]

Although biomimetic smart gating nanochannels have been explored extensively, research on practical applications of these systems is scarce. Here, we demonstrated an engineered track‐etched asymmetric porous polyethylene terephthalate (PET) membrane modified with redox‐active Cytochrome C (Cyt C), which served as a gatekeeper due to its redox‐responsive character and excellent anion selectivity. Due to the anion‐selectivity of the membrane, we further applied it in an energy conversion device to capture the electric power from a salinity gradient. In addition, its redox‐responsive property was utilized to realize the function of power switch in concentration cell, which is capable of out‐power density conversion from 0.24 W/m2 to 0.86 W/m2 reversibly. In addition, a theoretical model based on the Poisson and Nernst‐Planck equations has been employed to simulate and explain the experimental data and illustrate the mechanism of the ionic transport process. This work presents an important paradigm for the application of stimuli‐responsive nanochannels in salinity gradient energy conversion areas and opens new and promising routes in the fields of drug delivery and bioscience. [ABSTRACT FROM AUTHOR]

A new compound, [{Cu'(bim)}4{SiW12O40}] (1) (bim= l,2-bis(imidazol-l'-yl)ethane), was hydro-thermally synthesized and characterized by elemental analyses, IR, TG, and single-crystal X-ray diffraction. Compound 1 is an infinite 1-D chain composed of Cu-bim coordination polymers and [0C-SÍW12O40]4- polyanions. The electrochemical and electrocatalytic behaviors of l-modified car-bon paste electrode (1-CPE) have been studied. [ABSTRACT FROM AUTHOR]

A new organic–inorganic hybrid compound, [{Cu2(2,2′–bipy)2(pz)(gly)}2P2W18O62]·H2O (bipy = bipyridine, pz = pyrazine, gly = glycine) (1), has been hydrothermally synthesized and characterized by elemental analysis, IR, thermal gravimetric, and single- crystal X-ray diffraction. Compound1is an infinite one-dimensional (1-D) chain constructed from [P2W18O62]6−clusters andlinker exhibiting an alternating-type structure via equatorial terminal oxygens of the polyanion. The 1-D chains are further extended into 2-D layers and 3-D supramolecular network via weak interactions. The copper complex of1consists of three ligands, in which anin situglycine from pyrazine precursor was observed. Additionally, the electrochemical and electrocatalytic properties of1have been studied. [ABSTRACT FROM AUTHOR]

A Keggin-type polyoxometalate and potassium-sulfanilamide complex, [{K(C6H10N2O2S)2(H2O)}2(SiW12O40)2] · 2H3O+ · 10H2O (1), has been synthesized and characterized by elemental analyses, IR, TG, and single-crystal X-ray diffraction. Compound 1 exhibits infinite 1-D dimer chains which are constructed from Keggin units [α-SiW12O40]4− bridged by potassium-sulfanilamide fragments. These 1-D chains are linked via π–π interactions between benzene rings of the sulfanilamides to form 2-D layers, which are further packed into 3-D supramolecular assemblies through hydrogen bonds. The electrochemical and electrocatalytic behaviors of 1 have been studied in detail. [ABSTRACT FROM AUTHOR]

A 3-D complex K2[Ag2(biim)2]2P2W18O62 (biim = biimidazole) (1) has been hydrothermally synthesized and characterized by IR, thermogravimetric, and single-crystal X-ray diffraction. Single-crystal X-ray structural analysis reveals that 1 exhibits a 1-D wavelike chain constructed from µ3-bridging oxygen atoms of [P2W18O62]6− and [Ag2(biim)2]2+. The K+ link to six oxygen atoms of three P2W18 clusters and 12 equatorial terminal oxygen atoms of P2W18 clusters link to six K+, resulting in a 3-D framework with a relatively short Ag–Ag bond [2.836 Å]. The electrochemical behavior of 1 modified carbon paste electrode (1-CPE) has been studied. The results indicate that 1-CPE has remarkable stability. [ABSTRACT FROM AUTHOR]