Single Source Precursor Chemical Vapor Decomposition Method to Fabricate Stable, Bright Emissive Aluminum Hydroxide Phosphors for UV-Pumped White Light-Emitting Devices

Aluminum hydroxides are considered to be a potential abundant, low-cost blue emissive material to construct UV-pumped white light-emitting diodes (WLEDs). In this work, a single-source precursor chemical vapor decomposition method is adapted to fabricate stable, strongly emissive aluminum hydroxide phosphors with photoluminescence quantum yield of up to 69% in solid state by thermal decomposing aluminum diacetate hydroxide (Al(OH)(Ac)₂) at temperatures (260–360 °C) in N₂ atmosphere. It exhibits layered, amorphous structure and its emission of aluminum hydroxide is enhanced by electron-donating surface hydroxyl groups and originates from F⁺ centers and carbon-related defects contributing to UV (388 nm) and blue (450–520 nm) spectral regions, respectively. Employing the as-fabricated aluminum hydroxides as blue phosphor and CuInS₂ nanocrystals as red phosphor, high color rendering and high-efficiency WLEDs with luminous efficiencies up to 37 lm W⁻¹ and high color rendering index of 91 are fabricated. This is the best performance reported so far for aluminum hydroxide based LEDs.