Systematic investigation of chemical substitution in BaSnO$_{\mathrm{3}}$ using the combinatorial approach

BaSnO$_{\mathrm{3}}$ has been regarded as a possible material for photo-catalysis, dielectric capacitors, and transparent conductors. We are systematically investigating the effect of chemical substitution for A and B sites in BaSnO$_{\mathrm{3\thinspace }}$using a high-throughput methodology. We have thus far investigated the effect of substituting La and Sr for the Ba-site and Pb and Bi for the Sn-site. The composition spread films were prepared on MgO, SrTiO$_{\mathrm{3}}$ and LaAlO$_{\mathrm{3}}$ using combinatorial pulsed laser deposition. The lattice parameters and band-gap energies were found to continually change as a function of the concentration of each substitutional dopant. We find that the band gap can be tuned from 2.8 eV for BaSn$_{\mathrm{0.05}}$Pb$_{\mathrm{0.95}}$O$_{\mathrm{3}}$ to 4.5 eV for Ba$_{\mathrm{0.05}}$La$_{\mathrm{0.95}}$SnO$_{\mathrm{3}}$. Especially for Ba$_{\mathrm{1-x}}$La$_{\mathrm{x}}$SnO$_{\mathrm{3\thinspace }}$with x in the range of 0.05 \textless x\textless 0.5, we consistently observe resistivity as low as 0.23 m$\Omega $cm at room temperature while maintaining optical transparency with a typical bandgap of \textasciitilde 4 eV. The effect of crystalline defects on electrical properties will also be discussed.