Highly Conducting p-Type Transparent LnCuOS (Ln = La and Nd) and p-n Junction by Using Ink

The development of high performance p-type transparent conducting oxides (TCOs) remains as the greatest challenge to the achievement of advanced future optoelectronics including transparent electronics. In this work, we proposed and succeeded in designing a novel chemical solution method to prepare highly conducting p-type oxychalcogenides LnCuOS (Ln = La and Nd). Not only is our proposed chemical solution process much more economically efficient, versatile, and safer than all the currently available methods, but also the synthesized NdCuOS demonstrates the record high intrinsic p-type conductivity of 11.4 S cm(-1) for oxychalcogenides. The large improvement in the electrical conductivity is attributed to our synthesis process, leading to high Cu vacancies. The good phase stability of our highly Cu-deficient film was also proven by our computational calculation. At the same time, thin films of LnCuOS were also prepared via spin-coating methods for the first time. As the nanoparticles were used for spin-coating, the fabricated thin films are rather dense and smooth. Moreover, the strong photoluminescence (PL) peaks also indicate its great potential to be used in many future optoelectronics. The great performance demonstrated by the fabricated p-n junctions indicates the good opportunity to be integrated in devices like transparent electronics.