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Zn–Ni–Co–O wide-band-gap p-type conductive oxides with high work functions

  • A. Zakutayev (a1), J.D. Perkins (a1), P.A. Parilla (a1), N.E. Widjonarko (a2), A.K. Sigdel (a3), J.J. Berry (a4) and D.S. Ginley (a4)...


Co3O4-based spinels are a new class of wide-band-gap p-type conductive oxides with high work functions. We examined the structures, conductivities, work functions, and optical spectra of quaternary Zn–Ni–Co–O thin films across the entire spinel region of the ZnO–NiO–Co3O4 diagram using a high-throughput combinatorial approach. We found that the conductivity of as-deposited films is maximized (100 S/cm) and optical absorption (at 1.8 eV) is minimized in different regions of the diagram, while the work function of annealed films is high and relatively constant (5.8 ± 0.1 eV). These properties made Zn–Ni–Co–O thin films applicable as p-type interlayers in solar cells. As an example, amorphous Zn–Co–O hole transport layers had good performance in bulk heterojunction organic photovoltaic devices.


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Address all correspondence to A. Zakutayev


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Zn–Ni–Co–O wide-band-gap p-type conductive oxides with high work functions

  • A. Zakutayev (a1), J.D. Perkins (a1), P.A. Parilla (a1), N.E. Widjonarko (a2), A.K. Sigdel (a3), J.J. Berry (a4) and D.S. Ginley (a4)...


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