Cu:ZnInS/ZnS/ZnS:Al quantum dots (QDs) with a Cu-doped inner core and an Al-doped outer shell were synthesized in this work, exhibiting improved stability of luminescence, compared with Cu:ZnInS/ZnS/ZnS QDs. The X-ray diffraction patterns and photoluminescence spectra confirmed that the Al ions were doped into the ZnS shell. The stability of Cu:ZnInS/ZnS/ZnS:Al QDs under various thermal annealing temperatures was studied by steady-state and time resolved photoluminescence spectroscopy. The Cu: ZnInS/ZnS/ZnS:Al QDs had a relatively small reduction of 20% in photoluminescence lifetime from 167 ns under thermal annealing at 50 degrees C to 132.8 ns at 250 degrees C, compared to a 55% drop for the undoped ones, indicating less thermal effect on the photoluminescence of the QDs with an Al-doped shell. The Cu:ZnInS/ZnS/ZnS:Al QD-based light emitting diodes (LEDs) had a 3% luminescence enhancement under injection current of 10 mA for 30 h, compared to a 13% reduction for the undoped QDs, suggesting improved thermal stability of photoluminescence for the QDs with Al-doped shell. Finally, Cu:ZnInS/ZnS/ZnS:Al QD-based white LEDs with good color rendering index (>80.) and correlated color temperature (<4500 K) were fabricated by combining with green emitting CulnS(2)/ZnS QDs. The self-passivated QDs show promises for enhancing thermal stability of QD-based LEDs in the conserved energy lighting industry. (C) 2017 Elsevier Ltd. All rights reserved.