Abstract
Nanoparticles rich in oxygen vacancies (such as ZnO1-x, SnO2-x, TiO2-x, CeO2-x) are major components of Photoreversible color-switching systems (PCSSs) and are utilized in many applications (ink-free paper printing, secure communication and smart fabrics). Despite this, it has been a challenge to develop smart coatings due to several factors (such as low durability and poor efficiency in charge separation). To solve these issues, we have synthesized oxygen deficient vanadium oxide (VOx) quantum dots with a size of ∼ 2 nm through solvothermal reaction by using l-ascorbic acid as a reducing agent, resulting in widened photoabsorption spectrum with a band gap of 2.15 eV. Oxygen deficient VOx, methylene blue and acrylic latex (VOx/MB/Ac2403) have been used to design PCSSs coating on AA2024-T3 metal alloy. The redox dyes can be photocatalytically reduced by visible laser light, resulting in remote printing of various designs on the smart coating in ∼ 120 s. When irradiated with blue light, the designs can be erased in ∼ 250 s caused by the VOx self-catalyzed oxidation, leading to high recyclability (more than 40 cycles), efficiency and durability. As a result, reprintable smart coatings offer a viable alternative to regular alloys in meeting the growing demands for security or camouflage.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have