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Perylene molecules have been successfully implanted onto borosilicate glass plates, forming fluorescent features of 420 nm in diameter, using a method involving laser induced molecular micro-jet ejection through a water layer. The technique utilises a polymer source film in which perylene molecules are dispersed, a borosilicate glass substrate as a target and a pulsed laser. The space gap between the source film and the target is filled with liquid water. Perylene molecules dispersed in the polymer source films are photo-excited using 4-ns laser pulses resulting in the ejection of the molecules from the source matrix after which they become implanted into the target after passing through the water layer. This new advanced implantation method, using a laser induced molecular micro-jet through water, gives fine spatial control for fixing functional organic molecules in a designated region on hard dielectric materials and will have application in the fabrication of molecular devices, molecular sensors, and opto-electronics.

Laser induced molecular implantation technique (LIMIT) has been used for site-controlled fabrication of pixel arrays of organic light-emitting diodes in a form of dots with a diameter of several micrometers. N,N'-Bis(3-methylphenyl)-N,N'-diphenylbenzidine (TPD) dots, which were implanted into the poly(3,4-ethylene dioxythiophene)–poly(styrene sulphonate) (PEDOT–PSS) layer, act as recombination centers between the hole- and electron-transport layers in the indium tin oxide (ITO)/PEDOT–PSS/TPDdots/tris(8-hydroxyquinoline) aluminum (Alq3)/Mg–Ag sandwich structure, and illuminate intense green light. We studied fluorescence spectra of the implanted TPD dots and the dependence of their size and morphology on the intensity of a laser pulse, as well as the electroluminescence resulted from the organic light-emitting device (OLED) arrays. The site-controlled fabrication of such small OLEDs opens up an opportunity for production of electroluminescent devices with ultrahigh resolution.

We demonstrated highly efficient solar hydrogen generation via water splitting by photovoltaic–photoelectrochemical (PV–PEC) tandem device based on GaAs/InGaAsP (PV cell) and WO3/BiVO4 core/shell nanorods (PEC cell). We utilized extremely thin absorber (ETA) concept to design the WO3/BiVO4 core/shell heterojunction nanorods and obtained the highest efficiencies of generation, separation and transfer of the photo-induced charge carriers that are possible for the WO3/BiVO4 material combination. The PV–PEC tandem shows stable water splitting photocurrent of 6.56 mA·cm−2 under standard AM1.5G solar light that corresponds to the record solar-to-hydrogen (STH) conversion efficiency of 8.1%.

We have developed a technique for the fabrication of hierarchically organized micro/nano-structures of TiO2 by means of anodic oxidation of Ti nanorods prepared by glancing angle deposition. The fabricated nanostructures consist of small TiO2 nanotubes that form brush-type shells around long central oxide cores. This multiscale organization of the nanostructures satisfies requirements for large and accessible surface area while providing direct path for electrons, which are desirable for photocatalytic applications.