In this report we present a UV-Vis spectroscopic study of the pH dependent optical properties of 4,4'-azobenzene dicarboxylic acid in aqueous solution. A combination of chemical (acid-base) and light stimuli is combined to demonstrate that the system undergoes two types of optical switching cycles. At neutral pH the azobenzene undergoes photo-induced cis-trans isomerisation. Upon pH reduction the UV-Vis spectra show changes consistent with aggregation of the azobenzene photo-switch. The photo-responsive behaviour is dependent on the pH and conformation of the azobenzene. The optical properties of the system are dependent on the mode of pH reduction and the isomeric cis/trans composition of the photo-switch, showing hierarchical control of self-assembly.
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http://dx.doi.org/10.1016/j.saa.2019.117576 | DOI Listing |
J Mater Chem B
January 2025
Department of Advanced Materials Science & Engineering, Hanseo University, Seosan, Chungnam 31962, Republic of Korea.
MXenes are a class of 2D transition metal carbides and nitrides (MXT) that have attracted significant interest owing to their remarkable potential in various fields. The unique combination of their excellent electromagnetic, optical, mechanical, and physical properties have extended their applications to the biological realm as well. In particular, their ultra-thin layered structure holds specific promise for diverse biomedical applications.
View Article and Find Full Text PDFDalton Trans
January 2025
Department of Chemistry, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Organoboron complexes have garnered significant attention due to their remarkable optical properties and diverse applications. However, synthesizing stable fused five-, six- and seven-membered organoboron complexes possess significant challenges. In this study, we successfully developed novel mono-nuclear (6-8 & 10) and di-nuclear (9) organoboron complexes supported by triaminoguanidine-salicylidene based -symmetric Schiff base ligands one-step condensation reaction with excess phenylboronic acid.
View Article and Find Full Text PDFNanoscale Adv
January 2025
Energy Masteries Laboratory, Physics Department, School of Sciences and Engineering, The American University in Cairo New Cairo 11835 Egypt
Laser surface alloying of Fe, Si, and C on aluminium is demonstrated using a Q-switched Nd:YAG laser as the source of energy. The fundamental wavelength of the laser beam was 1064 nm with an output energy of 100 mJ and a pulse duration of 10 ns. The exposure was conducted in repetitive mode with a frequency rate of 1 Hz.
View Article and Find Full Text PDFNanoscale Adv
January 2025
Department of Production Engineering, Faculty of Mechanical Engineering, University of Aleppo Aleppo Syria
Adverse reactions caused by waterborne contaminants constitute a major hazard to the environment. Controlling the pollutants released into aquatic systems through water degradation has been one of the major concerns of recent research. Bismuth-based perovskites have exhibited outstanding properties in the field of photocatalysis.
View Article and Find Full Text PDFNanoscale Adv
January 2025
Department of Chemical Engineering, The Ilse Katz Institute for Nanoscience and Technology, Ben-Gurion University of the Negev Beer Sheva 84105 Israel
Entropy-driven assembly of nematic liquid-crystal phases of cellulose nanocrystals (SCNCs) in aqueous suspensions results in the emergence of a cholesteric liquid crystalline phase (N* phase). We report that a solvated, non-adsorbing, highly branched natural polysaccharide, Gum Arabic (GA), strongly affects the assembly of the SCNCs and modifies the phase diagram: GA leads to significant crowding of the SCNC rods and induces a new liquid-liquid phase transition, where SCNC-rich and GA-rich droplets coexist. The solvated GA does not induce coagulation or gelation of the suspended SCNCs (at low concentrations of 1-3 wt% of GA).
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