We address here the role of oxidation impurities on the structure of graphene oxide films at the air-water interface by specular neutron reflectivity (SNR). We study films of purified graphene oxide (PGO) and nonpurified graphene oxide in the close-packed state. Nonpurified graphene oxide is constituted by graphene oxide (GO) layers with oxidation impurities adsorbed on the basal plane, while in PGO sheets, impurities are eliminated. SNR measurements show that GO films are formed by well-defined bilayers constituted by 2-3 layers of GO stacked in contact with air and a second layer of impurities submerged in the aqueous subphase. In contrast, PGO films are formed by a single layer in contact with air. We show for the first time that impurities constitute a layer submerged in the aqueous subphase, decrease the elasticity, and favor the collapse of graphene oxide films. Our results allow designing the surface properties of GO trapped at fluid interfaces.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acsami.0c05649 | DOI Listing |
RSC Adv
January 2025
College of Food Science and Technology, Jiangsu Agri-animal Husbandry Vocational College Taizhou 225300 China
Bacterial infections are a major global health challenge, posing severe risks to human well-being. Although numerous strategies have been developed to combat bacterial pathogens, their practical application is often hindered by operational constraints. Photocatalytic materials have emerged as promising candidates for bacterial disinfection and food preservation due to their efficiency and sustainability.
View Article and Find Full Text PDFNanoscale Horiz
January 2025
Laboratory of Advanced Materials, Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Academy for Engineering & Technology, Advanced Coatings Research Center of Ministry of Education of China, Fudan University, Shanghai 200438, P. R. China.
A porous hedgehog-like CoO/NiO/graphene oxide (denoted as PHCNO/GO) microsphere was prepared by a facile solvothermal method, followed by an annealing treatment under argon atmosphere. Benefiting from the thin CoO/NiO nanosheets with a large specific surface area, abundant pores distributed between the CoO/NiO nanosheets, and GO firmly wrapped around the surface of PHCNO microspheres, the PHCNO/GO microspheres showed excellent lithium storage performance. The CoO/NiO nanosheets provided numerous active sites, achieving a high reversible specific capacity.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Peking University Shenzhen Graduate School, Shool of Chemical Biology and Biotechnology, Lishui Road, Nanshan District, -, Shenzhen, CHINA.
Regulating the coordination environment of active sites has proved powerful for tapping into their catalytic activity and selectivity in homogeneous catalysis, yet the heterogeneous nature of copper single-atom catalysts (SACs) makes it challenging. This work reports a bottom-up approach to construct a SAC (rGO@Cu-N(Hx)-C) by inlaying preformed amine coordinated Cu2+ units into reduced graphene oxide (rGO), permitting molecular level revelation on how the proximal N-site functional groups (N-H or N-CH3) impact on the carbon dioxide reduction reaction (CO2RR). It is demonstrated that the N-H moiety of rGO@Cu-NHx-C can serve as an in-situ protonation agent to accelerate the CO2-to-methane reduction kinetics, delivering a methane current density (163 mA/cm2) 2.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
School of Mechanical Engineering, Hebei University of Technology, Tianjin 300401, P. R. China.
Wirelessly driven flexible actuators are crucial to the development of flexible robotic crawling. However, great challenges still remain for the crawling of flexible actuators in complex environments. Herein, we reported a wireless flexible actuator synergistically driven by wireless power transmission (WPT) technology and near-infrared (NIR) light, which consists of a poly(dimethylsiloxane)-graphene oxide (PDMS-GO) composite layer, eutectic gallium-indium alloy (EGaIn), a PDMS layer, and a polyimide (PI) layer.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!