Atomically precise cluster-based white light emitters\(^{\S }\)

Materials emitting white luminescence are receiving increasing attention due to their potential applications in electroluminescent devices, information displays and fluorescent sensors. To produce white light, one must have either three primary colors, blue, green and red or two colors, blue and orange. In this paper, we have used thiol/phosphine protected red luminescent silver nanoclusters (Ag NCs), $$[\hbox {Ag}_{29}(\hbox {BDT})_{12}(\hbox {PPh}_{3})_{4} ]^{3\hbox {-}}\, (\hbox {BDT}=1,\!3\hbox {-benzenedithiol})$$ , $$[\hbox {Au}_{\mathrm{x}}\hbox {Ag}_{29\hbox {-}\mathrm{x}}(\hbox {BDT})_{12} (\hbox {PPh}_{3})_{4}]^{3\hbox {-}}$$ and $$\hbox {Ag}_{29}(\hbox {LA})_{12}$$ ( $$\hbox {LA}= \hbox {lipoic acid}$$ ) as one of the fluorophores for white light emission. These clusters are mixed with blue luminescent silicon nanoparticles (Si NPs) and green luminescent fluorescein isothiocyanate (FITC). The mixtures show white luminescence with CIE coordinates of (0.31, 0.34), (0.33, 0.35) and (0.29, 0.31) which are in good agreement with pure white light (0.33, 0.33). The other clusters with yellow, blue, orange, etc., luminescence can also be used to make white light. This work provides a prospective pathway for white light emission based on atomically precise noble metal NCs. Synopsis Monolayer protected noble metal nanoclusters such as $$[\hbox {Ag}_{29}(\hbox {BDT})_{12}(\hbox {PPh}_{3})_{4}]^{3\hbox {-}}\, (\hbox {BDT}=1,3\hbox {-benzenedithiol})$$ , $$[\hbox {Au}_{\mathrm{x}}\hbox {Ag}_{29\hbox {-}\mathrm{x}}(\hbox {BDT})_{12} (\hbox {PPh}_{3})_{4}]^{3\hbox {-}}$$ and $$\hbox {Ag}_{29}(\hbox {LA})_{12}$$ ( $$\hbox {LA}= \hbox {lipoic acid}$$ ) are used as red luminophores which can produce white light emission when mixed with blue luminescent silicon nanoparticles (Si NPs) and green luminescent fluorescein isothiocyanate (FITC). The mixtures produce white luminescence with CIE (Commission Internationale d’Eclair) coordinates of (0.31, 0.34), (0.33, 0.35) and (0.29, 0.31), respectively. All-cluster-based white light emission is indeed possible.