AgInS2-ZnS nanocrystals: Evidence of bistable states using light- induced electron paramagnetic resonance and photoluminescence

作者：Nobre Sonia S^*; Renard Olivier; Lombard Christian; Chevallier Theo; Pepin Donat Brigitte; Le Blevennec Gilles

来源：Physica Status Solidi-Rapid Research Letters, 2014, 8(4): 349-352.

DOI：10.1002/pssr.201308329

• nanocrystals
• photoluminescence
• electron paramagnetic resonance

The precursor (AgIn)(x) Zn2(1-x)(S2CN(C2H5)(2))(4) was used to prepared AgInS2-ZnS nanocrystals with different compositions (x = 0.4 and x = 0.7) and with different time of reaction (10 min and 75 min). The photoluminescence features of the nanocrystals were addressed by combining steady-state spectroscopy and light-induced electron paramagnetic resonance. Both techniques showed the contribution of at least two components for the emission, previously assigned to surface and intrinsic states. Light-induced electron paramagnetic resonance allowed detection of the photocreation both of irreversible paramagnetic species that are likely responsible for the nano-crystals degradation assigned to surface states and of reversible paramagnetic species assigned to intrinsic states. Moreover, reversible bistable paramagnetic states were observed. This Letter provides a scheme that might be useful in addressing the well-known problem of aging of the nanocrystals.

• 出版日期2014-4
• 单位中国地震局