Surface Engineering Quantum Dots at the Air-Water Interface
Quantum dots (QD) have been modified with surfactants of varying chain lengths. These QD-surfactants can form a stable monolayer at the air-water interface. A possible explanation for the different behaviors of modified QDs may be found in the roles of trioctylphosphine oxide on the QD surface. It has been shown that QD are submicron-sized structures that are able to confine excitons in one or more directions. Electron confinement in all three dimensions is called “quantum confinement,” and the particles QD with a main characteristic of discrete levels of energy not continuous such as in metals. Langmuir films are formed by spreading an amphiphilic molecule at the air-water interface and its interface properties are studied upon compression of the film. The main requirement of the molecule is that the solvent in which it is dissolved should be immiscible with water and fairly volatile.