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Electrocatalytic performance of low-cost graphitic carbon nitride (g-C 3 N 4 ) is greatly limited by its conductivity. In this work, an innovative method, gamma irradiation technology, was used to efficiently synthesize g-C 3 N 4 /Pt nanoparticle (CN/Pt) nanocomposites, which can construct conductive channels between the nanostructure g-C 3 N 4 and supported platinum nanoparticles (PtNPs). Then, the as-prepared CN/Pt nanocomposites were applied in the oxygen reduction reaction (ORR) as an electrocatalyst, which shows a small Tafel slope and the fast four-electron transfer path in the ORR. The oxygen reduction performance over the CN/Pt nanocomposite is much superior to that of the commercial Pt/C and mostly reported in g-C 3 N 4 -based electrodes. Experimental results have confirmed the fast charge transfer between PtNPs and g-C 3 N 4 through a metal-support interaction, and using gamma irradiation technique to disperse PtNPs on g-C 3 N 4 proves to be an effective strategy to enhance the catalytic performance of g-C 3 N 4 in ORR. Therefore, gamma irradiation may possess great potential for preparing CN/Pt nanocomposites as a highly efficient ORR catalyst.

Realizing that one main factor affecting development of forward osmosis (FO) membrane was internal concentration polarization (ICP), graphene oxide (GO) with two-dimensional structure and oxidized carbon nanotubes (OCNTs) with one-dimensional structure were linked by oxygen-containing groups to form water channels in the polyamide layer. OCNTs and GO were used for producing reactions among oxygen-containing groups of nanoparticles and polymer chains, and oxygen-containing groups were fully exposed because GO and OCNTs restrained aggregation. Decrease of cross-linking degree for interfacial polymerization layer was confirmed due to reaction from GO/OCNTs/m-phenylene diamine/1,3,5-benzenetricarbonyl trichloride. Moreover, OCNTs formed an appropriate supporting effect for GO to improve hydrophilic properties, which was confirmed by transmission electron microscopy, scanning electron microscope and contact angle. Resulting membrane PA-GO-OCNTs showed high water flux (114 LMH and 84.6 LMH in the PRO (active layer facing draw solution) and FO (active layer facing feed solution) mode, respectively) and low solute flux (5.17 gMH and 3.4 gMH in the PRO and FO mode, respectively) under this condition that 0.5 M NaCl and deionized water were used as draw solution and feed solution respectively. It was worth mentioning that water flux of FO membrane was far higher than that in reported literatures while its structural parameter S was only 203 μm, which led to decrease of ICP., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Fibrous mats piled by nitrogen-doped porous carbon nanofibers with seeded TiO 2 are fabricated and punched directly into circles as lithium-ion battery anodes. The seeding structure is composed of semi-wrapped TiO 2 nanoparticles on carbon nanofibers (CNFs) coated with a thin layer of carbon. Synchronously, pores with various widths are formed on CNFs. As a freestanding anode, an initial discharge capacity of 615 mAh g -1 with a coulombic efficiency of 56% is reached, and 322 mAh g -1 is obtained after 100 cycles at a current density of 100 mA g -1 . This is assigned to the increasing number of active sites for the lithium ion from pores with various widths and improved conductivity originating from nitrogen doping. Superior rate performance (179 mAh g -1 at the current density of 2000 mA g -1 ) under various current densities compared with that of other counterparts is attributed to the structural stability originating from the seeding structure with the help of the C-O-Ti bond. An additional 800 cycles are displayed at the current density of 2000 mA g -1 , and superior stability is also exhibited.

N-Alkylated chitosan (NACS) may improve the haemostatic efficiency of chitosan (CS). To study its coagulation capability and function, a series of NACS with various carbon chain lengths and substitution degrees (SD) of alkyl groups were synthesized and characterized by FTIR, NMR, and elemental analysis. Haemolysis and toxicity assays revealed that NACS showed good biocompatibility. In vitro blood clotting tests indicated that NACS had better haemostatic activity than CS, of which N-octadecyl CS with 3.85% SD showed the best results. Blood plasma coagulation tests showed that NACS was not favourable for activating coagulation factors. Platelet adhesion, intracellular Ca 2+ , and CD62p measurements demonstrated that the coagulation properties of NACS were not related to platelet activation. Erythrocyte adhesion examination indicated that blood coagulation of NACS may be attributable to its effects on erythrocytes. This study suggests that NACS is an ideal candidate for clotting., (Copyright © 2017 Elsevier Ltd. All rights reserved.)