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We recently developed a rapid single-step calcium phosphate (CaP) precipitation technique on several substrates using a laser-assisted biomimetic process (LAB process). In this process, ultraviolet (UV, λ  =  355 nm) pulsed laser irradiation has been applied to a substrate that is immersed in a supersaturated CaP solution. In the present study, the LAB process for CaP precipitation on a titanium substrate was successfully expanded to include not only UV but also visible (VIS, λ  =  532 nm) and near infrared (NIR, λ  =  1064 nm) lasers. Surface heating and plasma-mediated surface reactions (micro-deformation, oxidization, photoexcitation, and wetting) generated by UV, VIS, or NIR lasers are considered to be involved in the CaP precipitation on the titanium surface in the LAB process. The kinetics of these reactions and consequently of CaP precipitation were dependent on the laser wavelength and fluence. The higher laser fluence did not always accelerate CaP precipitation on the substrate; rather, it was found that an optimal range of fluence exists for each laser wavelength. These results suggest that for efficient CaP precipitation, a suitable laser wavelength should be selected according to the optical absorption properties of the substrate material and the laser fluence should also be adjusted to induce surface heating and plasma-mediated surface reactions that are favorable for CaP precipitation. [ABSTRACT FROM AUTHOR]

The dielectric constant is a keyparameter that determines both optical and electronic properties ofmaterials. It is desirable to tune electronic properties though dielectricengineering approach. Here, we present a systematic approach to tunecarrier mobilities of hybrid inorganic/organic materials where layeredtwo-dimensional transition-metal dichalcogenide TiS2iselectrochemically intercalated with polar organic molecules. By manipulatingthe dielectric mismatch using polar organic molecules with differentdielectric constants, ranging from 10 to 41, the electron mobilityof the TiS2layers was changed three times due to the dielectricscreening of the Coulomb-impurity scattering processes. Both the overallthermal conductivity and the lattice thermal conductivity were alsofound to decrease with an increasing dielectric mismatch. The enhancedelectrical mobility along with the decreased thermal conductivitytogether gave rise to a significantly improved thermoelectric figureof merit of the hybrid inorganic/organic materials at room temperature,which might find applications in wearable electronics. [ABSTRACT FROM AUTHOR]