In this study, we demonstrate interface engineering to develop an efficient and stable p-type Cu2O photoanode for solar water oxidation in both neutral and strongly basic electrolyte solutions. The use of ITO/TiO2/Ga2O3 as back contact layers and Al2O3/Au/NiFe as front layers effectively addressed challenges associated with poor minority carrier transport and high charge recombination. The champion Cu2O photoanode achieved a photocurrent density of 8.65 mA cm -2 at 1.23 V vs. RHE, the highest so far reported for an oxide light absorber. Our findings highlight the importance of selective contact design in enabling efficient minority charge carrier collection, thereby demonstrating the viability of using p-type semiconductors as the photoanode for PEC oxidation reactions. Future research could build on these insights to explore alternative oxidation reactions or enhance the durability and the catalytic activity of photoanodes in water oxidation, paving the way for high-performance PEC systems for solar energy conversion.