Send to

Choose Destination
J Phys Chem Lett. 2019 May 27. doi: 10.1021/acs.jpclett.9b01405. [Epub ahead of print]

Band Alignment Boosts Charge-Carrier Collection in Sn-Based Perovskite over Pb Counterparts.


The diverse elemental compositions endow metal halide perovskites with tailorable electronic structures and broad optoelectronic applications. For Sn-based perovskites, their bandedge positions, which govern interfacial charge-carrier transport, are less well studied than their Pb counterparts. In this work, the valence band maximum (VBM) of CsSnBr3 was experimentally and theoretically determined to be -5.2 eV, to which Au forms a good contact. The conduction band minimum (CBM) of CsSnBr3 at -3.4 eV is matched by 1,3,5-tris(4-phenylquinolin-2-yl)benzene (TQB), an organic electron transport material and a ligand to Sn(II). Thanks to proper band alignment, the device structure Al/TQB/CsSnBr3/Au constitutes a photodetector responsive to the entire visible spectrum without a bias voltage, and outperforms Pb-based devices under similar conditions. Our results highlight the advantage of combined experimental and theoretical tools in understanding intrinsic material properties and guiding device fabrication.

Supplemental Content

Full text links

Icon for American Chemical Society
Loading ...
Support Center