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Heterogeneous structures in nacre‐mimetic 2D layered materials generate novel transport phenomena in angstrom range, and thus provide new possibilities for innovative applications for sustainable energy, a clean environment, and human healthcare. In the two orthogonal transport directions, either vertical or horizontal, heterostructures in horizontal direction have never been reported before. Here, a 2D‐material‐based laterally heterogeneous membrane is fabricated via an unconventional dual‐flow filtration method. Negatively and positively charged graphene oxide multilayers are laterally patterned and interconnected in a planar configuration. Upon visible light illumination on the bipolar nanofluidic heterojunction, protons are able to move uphill against their concentration gradient, functioning as a light‐harvesting proton pump. A maximum proton concentration gradient of about 5.4 pH units mm−2 membrane area can be established at a transport rate up to 14.8 mol h−1 m−2. The transport mechanism can be understood as a light‐triggered asymmetric polarization in surface potential and the consequent change in proton capacity in separate parts. The implementation of photonic–ionic conversion with abiotic materials provides a full‐solid‐state solution for bionic vision and artificial photosynthesis. There is plenty of room to expect the laterally heterogeneous membranes for new functions and better performance in the abundant family of liquid processable colloidal 2D materials. [ABSTRACT FROM AUTHOR]

Numerous reported bioinspired osmotic energy conversion systems employing cation‐/anion‐selective membranes and solutions with different salinity are actually far from the biological counterpart. The iso‐osmotic power generator with the specific ionic permselective channels (e.g. K+ or Na+ channels) which just allow specific ions to get across and iso‐osmotic solutions still remain challenges. Inspired by nature, we report a bioinspired K+‐channel by employing a K+ selective ligand, 1,1,1‐tris{[(2′‐benzylaminoformyl)phenoxy]methyl}ethane (BMP) and graphene oxide membrane. Specifically, the K+ and Na+ selectivity of the prepared system could reach up to ≈17.8, and the molecular dynamics simulation revealed that the excellent permselectivity of K+ mainly stemmed from the formed suitable channel size. Thus, we assembled the K+‐selective iso‐osmotic power generator (KSIPG) with the power density up to ≈15.1 mW/m2 between equal concentration solutions, which is higher than traditional charge‐selective osmotic power generator (CSOPG). The proposed strategy has well shown the realizable approach to construct single‐ion selective channels‐based highly efficient iso‐osmotic energy conversion systems and would surely inspire new applications in other fields, including self‐powered systems and medical materials, etc. [ABSTRACT FROM AUTHOR]

Numerous reported bioinspired osmotic energy conversion systems employing cation‐/anion‐selective membranes and solutions with different salinity are actually far from the biological counterpart. The iso‐osmotic power generator with the specific ionic permselective channels (e.g. K+ or Na+ channels) which just allow specific ions to get across and iso‐osmotic solutions still remain challenges. Inspired by nature, we report a bioinspired K+‐channel by employing a K+ selective ligand, 1,1,1‐tris{[(2′‐benzylaminoformyl)phenoxy]methyl}ethane (BMP) and graphene oxide membrane. Specifically, the K+ and Na+ selectivity of the prepared system could reach up to ≈17.8, and the molecular dynamics simulation revealed that the excellent permselectivity of K+ mainly stemmed from the formed suitable channel size. Thus, we assembled the K+‐selective iso‐osmotic power generator (KSIPG) with the power density up to ≈15.1 mW/m2 between equal concentration solutions, which is higher than traditional charge‐selective osmotic power generator (CSOPG). The proposed strategy has well shown the realizable approach to construct single‐ion selective channels‐based highly efficient iso‐osmotic energy conversion systems and would surely inspire new applications in other fields, including self‐powered systems and medical materials, etc. [ABSTRACT FROM AUTHOR]

Light-driven proton directional transport is important in living beings as it could subtly realize the light energy conversion for living uses. In the past years, 2D materials-based nanochannels have shown great potential in active ion transport due to controllable properties, including surface charge distribution, wettability, functionalization, electric structure, and external stimuli responsibility, etc. However, to fuse the inorganic materials into bio-membranes still faces several challenges. Here, we proposed peptide-modified WS 2 nanosheets via cysteine linkers to realize tunable band structure and, hence, enable light-driven proton transmembrane transport. The modification was achieved through the thiol chemistry of the –SH groups in the cysteine linker and the S vacancy on the WS 2 nanosheets. By tuning the amino residues sequences (lysine-rich peptides, denoted as KFC; and aspartate-rich peptides, denoted as DFC), the ζ-potential, surface charge, and band energy of WS 2 nanosheets could be rationally regulated. Janus membranes formed by assembling the peptide-modified WS 2 nanosheets could realize the proton transmembrane transport under visible light irradiation, driven by a built-in potential due to a type II band alignment between the KFC-WS 2 and DFC-WS 2. As a result, the proton would be driven across the formed nanochannels. These results demonstrate a general strategy to build bio-semiconductor materials and provide a new way for embedding inorganic materials into biological systems toward the development of bioelectronic devices. • The designed peptides could be well modified to WS 2 nanosheets through the cysteine linker. • The electronic band structures of the peptide-WS 2 nanosheets were verified through experiments and theoretical calculation. • The assembled bio-semiconductor membrane could realize the light-driven proton transmembrane transport. [ABSTRACT FROM AUTHOR]

Carbon/carbon composites pretreated by an argon plasma were coated by hydroxyapatite (HA) using a plasma spraying method. The morphology, the compositions of the coating and bond strength between HA and substrate were investigated by scanning electron microscopy, X-ray diffraction, infrared spectrometry and a scratching test. Results indicate that although the morphology and phase compositions of the HA coating are similar, the substrate critical load, above which apparent spallation of the coating occurs, was 14.0 and 8.9N with or without the pretreatment respectively, indicating that the argon plasma pretreatment improves the bond strength between the coating and the substrate. [New Carbon Materials 2013, 28(3): 215–221] [ABSTRACT FROM AUTHOR]