Well-defined molecular layers can be formed on the surface of nanocrystalline anatase TiO2 by photochemically grafting organic molecules bearing a terminal vinyl group. The molecular layers produced are shown to have minimal oxidation and are able to be patterned and uniformly grafted through optically thick nanocrystalline films. Stability tests show that the layers have excellent stability in deionized water at 80 degrees C, aqueous solutions at pH=1.0 and pH=10.3 at 65 degrees C, and acetonitrile for time scales approaching 1200 h. Degradation of the films in deionized water occurs using a AM1.5 full-spectrum solar simulator as an illumination source but is partially suppressed by filtering with a 400 nm UV blocking filter which blocks the above-bandgap light. A mechanism is proposed for the grafting reaction in which the surface hydroxyl groups trap photoexcited holes, facilitating reaction with the vinyl group.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/la901116c | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
In Situ Raman Spectroscopy for Early Corrosion Detection in Coated AA2024-T3.
Sensors (Basel)
December 2024
TDA Research Inc., Golden, CO 80403, USA.
Here we describe the synthesis and evaluation of a molecular corrosion sensor that can be applied in situ in aerospace coatings, then used to detect corrosion after the coating has been applied. A pH-sensitive molecule, 4-mercaptopyridin (4-MP), is attached to a gold nanoparticle to allow surface-enhanced Raman-scattering (SERS) for signal amplification. These SERS nanoparticles, when combined with an appropriate micron-sized carrier system, are incorporated directly into an MIL-SPEC coating and used to monitor the process onset and progression of corrosion using pH changes occurring at the metal-coating interface.
View Article and Find Full Text PDFOrganic Optocoupler with Simple Construction as an Effective Linear Current Transceiver.
Materials (Basel)
January 2025
ABB Corporate Technology Center, 13A Starowislna Str., 31-038 Krakow, Poland.
In this study, it is shown that an efficient organic optocoupler (OPC) can be fabricated using commercially available and solution-processable organic semiconductors. The transmitter is a single-active-layer organic light-emitting diode (OLED) made from a well-known polyparavinylene derivative, Super Yellow. The receiver is an organic light-emitting diode (OLSD) with a single active layer consisting of a mixture of the polymer donor PTB7-Th and the low-molecular-weight acceptor ITIC; the receiver operates without an applied reverse voltage.
View Article and Find Full Text PDFEffects of Beech Wood Surface Treatment with Polyethylenimine Solution Prior to Finishing with Water-Based Coating.
Polymers (Basel)
December 2024
Faculty of Forestry, University of Belgrade, 11030 Belgrade, Serbia.
The surfaces of beech wood samples were treated with polyethylenimine (PEI) solutions at three different concentrations-0.5%, 1% and 2%-and two molecular weights-low molecular weight (LMW) and high molecular weight (HMW). The effects of PEI surface treatment of wood were characterized by FT-IR spectroscopy, the penetration depth of PEI (EPI fluorescence spectroscopy), the bonding position of PEI (by SEM), the wetting and surface energy, and the water uptake.
View Article and Find Full Text PDFDimer Is Not Double: The Unexpected Behavior of Two-Floor Peptide Nanosponge.
Molecules
December 2024
Department of Chemical Science and Technologies, University of Rome "Tor Vergata", Via della Ricerca Scientifica, 00133 Rome, Italy.
Using the framework of an investigation of the stimuli-responsive behavior of peptide assembly on a solid surface, this study on the behavior of a chemisorbed peptide on a gold surface was performed. The studied peptide is a dimeric form of the antimicrobial peptide Trichogin GAIV, which was also modified by substituting the glycine with lysine residues, while the N-terminus octanoyl group was replaced by a lipoic one that was able to bind to the gold surface. In this way, a chemically linked peptide assembly that is pH-responsive was obtained because of the protonation/deprotonation of the sidechains of the Lys residues.
View Article and Find Full Text PDFFabrication of Compartmentalized Multienzyme Reactor for Colorimetric Biosensing of Glucose and Phenol with High Sensitivity.
ACS Appl Mater Interfaces
January 2025
College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, P. R. China.
Enzymatic cascade reactions are widely utilized in food security, environmental monitoring, and disease diagnostics, whereas their practical application was hindered due to their limited catalytic efficiency and intrinsic fragility to environmental influences. Herein, a compartmentalized dual-enzyme cascade nanoreactor was constructed in metal-organic frameworks (ZIF-8) by a shell-by-shell growth method. ZIF-8 provided a good microenvironment to maintain the activity of enzymes and protected them against harsh conditions.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!