Sacrificial oxidation of a self-metal source for the rapid growth of metal oxides on quantum dots towards improving photostability

Abstract

A sacrificial oxidation of a self-metal source strategy to rapidly anchor metal oxides on individual QD surfaces for improved photostability was reported.

Surface Oxidation of Quantum Dots to Improve the Device Performance of Quantum Dot Light-Emitting Diodes

“…Higher EQE means less Joule heating produced by the nonradiative recombination pathway and less deterioration under operational conditions. In addition, according to our previous works, 22,25 the Al doping and oxidation treatment could improve the stability of QDs. Thus, the oxide layer produced by the Al doping and oxidation treatment also enhances the heat stability of QDs and resists the intrusion of water and air.…”

“…X-ray photoelectron spectroscopy characterization (Figure S10) also shows the difference in the Al 2p spectra between QDs without BPO treatment and with BPO treatment. After BPO treatment, the Al 2p peak shows a new peak that shifted to a lower binding energy, which means the appearance of Al–O . The presence of insulating Al 2 O 3 could inhibit the transfer of charge, which likes the role of poly­(methyl methacrylate) in Peng’s work .…”

“…After BPO treatment, the Al 2p peak shows a new peak that shifted to a lower binding energy, which means the appearance of Al− O. 25 The presence of insulating Al 2 O 3 could inhibit the transfer of charge, which likes the role of poly(methyl methacrylate) in Peng's work. 17 The electron current was slowed by the oxide layer, which was consistent with the reduction of average electron mobility.…”

“…The TFB layer was deposited by spin-coating on the ITO-glass/PEDOT:PSS substrate at 2000 rpm for 20 s using a chlorobenzene solution (8 mg mL –1 ) and annealed at 150 °C for 30 min. The QDs were all dispersed in n -octane (10 mg mL –1 ) and spin-coated onto the ITO-glass/PEDOT:PSS/TFB substrates at 2000 rpm for 20 s. To investigate the effect of Al doping and oxidation treatment, three types of QLEDs with the same architecture were fabricated using three different kinds of QDs: CdSe/CdS/ZnS QDs, CdSe/CdS:Al/ZnS:Al QDs, and CdSe/CdS:Al/ZnS:Al-BPO-1 h [benzoyl peroxide (BPO) treatment with 1 h] QDs. The ZnO layer was deposited by spin-coating an n -butyl alcohol solution (30 mg mL –1 ) at 3000 rpm and annealed at 70 °C for 30 min.…”

Degradation Dynamics of Quantum Dots in White LED Applications

“…The transition state search (TSS) module of the MedeA software is used to observe the energy changes between the initial and nal structures [38,43] . In the TSS module, we employ Nudged elastic band (NEB) method [43,44] to map the minimum energy path (MEP) between the initial and the nal systems by calculating the free energy (ΔG) barriers at different reaction stages. The stage closest to a saddle point is allowed to climb up into the saddle point (cNEB method) if the largest force on an atom is smaller than 1.0 eV Å −1 .…”