title: Highly efficient large-area colourless luminescent solar concentrators using heavy-metal-free colloidal quantum dots.
abstract: Luminescent solar concentrators serving as semitransparent photovoltaic windows could become an important element in net zero energy consumption buildings of the future. Colloidal quantum dots are promising materials for luminescent solar concentrators as they can be engineered to provide the large Stokes shift necessary for suppressing reabsorption losses in large-area devices. Existing Stokes-shift-engineered quantum dots allow for only partial coverage of the solar spectrum, which limits their light-harvesting ability and leads to colouring of the luminescent solar concentrators, complicating their use in architecture. Here, we use quantum dots of ternary I-III-VI2 semiconductors to realize the first large-area quantum dot-luminescent solar concentrators free of toxic elements, with reduced reabsorption and extended coverage of the solar spectrum. By incorporating CuInSexS2-x quantum dots into photo-polymerized poly(lauryl methacrylate), we obtain freestanding, colourless slabs that introduce no distortion to perceived colours and are thus well suited for the realization of photovoltaic windows. Thanks to the suppressed reabsorption and high emission efficiencies of the quantum dots, we achieve an optical power efficiency of 3.2%. Ultrafast spectroscopy studies suggest that the Stokes-shifted emission involves a conduction-band electron and a hole residing in an intragap state associated with a native defect.
authors: Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, via Cozzi 55, Milano I-20125, Italy.
authors: Francesco
authors: F
authors: Meinardi
authors: Center for Advanced Solar Photophysics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.|UbiQD, Los Alamos, New Mexico 87544, USA.
authors: Hunter
authors: H
authors: McDaniel
authors: Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, via Cozzi 55, Milano I-20125, Italy.
authors: Francesco
authors: F
authors: Carulli
authors: Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, via Cozzi 55, Milano I-20125, Italy.
authors: Annalisa
authors: A
authors: Colombo
authors: Theoretical Division &Center for Advanced Solar Photophysics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: Kirill A
authors: KA
authors: Velizhanin
authors: Center for Advanced Solar Photophysics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: Nikolay S
authors: NS
authors: Makarov
authors: Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, via Cozzi 55, Milano I-20125, Italy.
authors: Roberto
authors: R
authors: Simonutti
authors: Center for Advanced Solar Photophysics, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: Victor I
authors: VI
authors: Klimov
authors: Dipartimento di Scienza dei Materiali, Università degli Studi di Milano-Bicocca, via Cozzi 55, Milano I-20125, Italy.
authors: Sergio
authors: S
authors: Brovelli