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arXiv · 1906.02432

Enhanced Photovoltaic Performance of Perovskite Solar Cells by Co-Doped Spinel Nickel Cobaltite Hole Transporting Layer

Apostolos Ioakeimidis·Ioannis T. Papadas·Dimitris Tsikritzis·Gerasimos S. Armatas·Stella Kennou·Stelios A. Choulis
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Abstract

Solution combustion synthesized hole transport layer of co-doped spinel nickel cobaltite were fabricated using doctor-blading technique for planar inverted perovskite solar cells. Perovskite solar cells incorporating Co-doped spinel nickel cobaltite shown an increase in device performance parameters compared to un-doped spinel nickel cobaltite, leading to PCE of 16.5%. X-ray photoelectron spectroscopy measurements revealed the tendency of Cu cations to replace preferably the surface Ni atoms changing the surface stoichiometry of spinel nickel cobaltite inducing a cathodic polarization. Ultraviolet photoelectron spectroscopy measurements unveiled the increase of the ionization potential by 0.1 eV for co-doped spinel nickel cobaltite film compare to undoped spinel nickel cobaltite-based hole transporting layer. We attribute the enhanced PCE of inverted perovskite solar cells presented due to improved hole extraction properties of co-doped spinel nickel cobaltite hole transporting layer.

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Apostolos Ioakeimidis, Ioannis T. Papadas, Dimitris Tsikritzis, Gerasimos S. Armatas, Stella Kennou, Stelios A. Choulis. 2019-06-06. Enhanced Photovoltaic Performance of Perovskite Solar Cells by Co-Doped Spinel Nickel Cobaltite Hole Transporting Layer. https://doi.org/10.1063/1.5079954

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