title: Tunable light emission by exciplex state formation between hybrid halide perovskite and core/shell quantum dots: Implications in advanced LEDs and photovoltaics.
abstract: We report the first observation of exciplex state electroluminescence due to carrier injection between the hybrid lead halide perovskite (MAPbI3-xClx) and quantum dots (core/shell PbS/CdS). Single layers of perovskite (PS) and quantum dots (QDs) have been produced by solution processing methods, and their photoluminescent properties are compared to those of bilayer samples in both PS/QD and QD/PS configurations. Exciplex emission at lower energies than the band gap of both PS and QD has been detected. The exciplex emission wavelength of this mixed system can be simply tuned by controlling the QD size. Light-emitting diodes (LEDs) have been fabricated using those configurations, which provide light emission with considerably low turn-on potential. The "color" of the LED can also be tuned by controlling the applied bias. The presence of the exciplex state PS and QDs opens up a broad range of possibilities with important implications not only in tunable LEDs but also in the preparation of intermediate band gap photovoltaic devices with the potentiality of surpassing the Shockley-Queisser limit.
authors: Institute of Advanced Materials (INAM), Universitat Jaume I, 12006 Castelló, Spain.
authors: Rafael S
authors: RS
authors: Sanchez
authors: Institute of Advanced Materials (INAM), Universitat Jaume I, 12006 Castelló, Spain.
authors: Mauricio Solis
authors: 0000-0003-0759-0907
authors: MS
authors: de la Fuente
authors: UMDO, Instituto de Ciencia de los Materiales, Universidad de Valencia, 46071 Valencia, Spain.
authors: Isaac
authors: 0000-0002-2773-8801
authors: I
authors: Suarez
authors: UMDO, Instituto de Ciencia de los Materiales, Universidad de Valencia, 46071 Valencia, Spain.
authors: Guillermo
authors: G
authors: Muñoz-Matutano
authors: UMDO, Instituto de Ciencia de los Materiales, Universidad de Valencia, 46071 Valencia, Spain.
authors: Juan P
authors: 0000-0003-3683-0578
authors: JP
authors: Martinez-Pastor
authors: Institute of Advanced Materials (INAM), Universitat Jaume I, 12006 Castelló, Spain.
authors: Ivan
authors: 0000-0003-2508-0994
authors: I
authors: Mora-Sero
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry*; D003116:Color; D004563:Electrochemistry / Q000295:instrumentation; D008027:Light; D049449:Luminescence; D036103:Nanotechnology / Q000295:instrumentation*; D010087:Oxides / Q000737:chemistry*; D045663:Quantum Dots / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D010087:Oxides; C059910:perovskite; D014025:Titanium
keywords: Physics; exciplex state formation; light emitting devices (LEDs); perovskites; photovoltaics; quantum dots