Electrochemical synthesis of flat-[Ga 13−x In x (μ 3 -OH) 6 (μ-OH) 18 (H 2 O) 24 (NO 3 ) 15 ] clusters as aqueous precursors for solution-processed semiconductors
Published Web Location
https://doi.org/10.1039/c4tc01354a
Abstract
Electrochemical reduction is used to synthesize indium-gallium-hydroxide-nitrate nanoclusters which are shown to be promising precursors for thin-film transistors.
Flat-[Ga 13 (μ 3 -OH) 6 (μ-OH) 18 (H 2 O) 24 ](NO 3 ) 15 (Ga 13 ) and heterometallic [Ga 13−x In x (μ 3 -OH) 6 (μ-OH) 18 (H 2 O) 24 ](NO 3 ) 15 ( x = 5, 4) clusters were synthesized by the electrolysis of metal nitrate salt solutions to directly form, without purification, aqueous precursor inks for In x Ga 13−x O y semiconducting films in <2 h. Raman spectroscopy and 1 H-NMR spectroscopy confirm the presence of [Ga 13−x In x (μ 3 -OH) 6 (μ-OH) 18 (H 2 O) 24 (NO 3 ) 15 ] clusters. Bottom-gate thin-film transistors were fabricated using ∼15 nm-thick Ga 13−x In x O y films as the active channel layer, displaying turn-on voltages of −2 V, and on/off current ratios greater than 10 6 . The average channel mobility of the transistors fabricated from the cluster solutions generated by electrolysis was ∼5 cm −2 V −1 s −1 which was more than twice that of transistors fabricated from control solutions with the simple nitrate salt precursors of ∼2 cm −2 V −1 s −1 . Electrochemical cluster synthesis thus provides a simple and direct route to aqueous precursors for solution-processed inorganic electronics.
Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.