Overcoming Phase?Purity Challenges in Complex Metal Oxide Photoelectrodes: A Case Study of CuBi ₂ O ₄

The widespread application of solar-water-splitting for energy conversion depends on the progress photoelectrodes that uphold stringent criteria from photoabsorber materials. After investigating almost all possible elemental and binary semiconductors, search must be expanded to complex Yet, high structural control these materials will become more challenging with an increasing number elements. Complex metal-oxides offer unique advantages as photoabsorbers. However, practical fabrication conditions when using glass-based transparent conductive-substrates low thermal-stability impedes use common synthesis routes high-quality metal-oxide thin-film photoelectrodes. Nevertheless, rapid thermal processing (RTP) enables heating at higher temperatures than stabilities substrates, circumventing this bottleneck. Reported here is approach overcome phase-purity challenges in metal-oxides, showing importance attaining a single-phase multinary compound by exploring large growth parameter spaces, achieved employing combinatorial study CuBi2O4, prime candidate photoabsorber. Pure CuBi2O4 are synthesized after studying relationship between crystal-structures, conditions, RTP, properties over range thicknesses. Single-phase exhibit fill-factors, photoconversion efficiencies, longer carrier lifetimes, increased stability nonpure These findings show impact approaches alongside radiative techniques toward discovering highly efficient