Scalable synthesis of delafossite CuAlO2 nanoparticles for p-type dye-sensitized solar cells applications

Highlights: • Scalable synthesis method for CuAlO2 nanoparticles described. • High cathodic photocurrents observed compared to previous reports. • Particle size analyzed using TEM and WPPM. -- Abstract: Delafossite CuAlO2 nanoparticles were prepared using an easily scalable method under controlled partial oxygen pressure (pO2) of 10−5 atm at 775 °C. Transmission electron microscopy showed a uniform particle size of 35 nm, agreeing well with the calculated particle size distribution obtained using the Whole Powder Pattern Method (WPPM) via the PM2K software package. Higher cathodic photocurrents (Jsc = 0.954 mA/cm2 under AM1.5 sun) were observed in p-type dye sensitized solar cells (DSSCs) fabricated using these CuAlO2 nanoparticles compared to the previous reports on delafossite CuBO2 (B = Al, Ga) nanoparticles. Enhanced current efficiency in these solar cells is attributed to the nano-sized particles and narrow particle size distributions of nanocrystalline delafossite CuAlO2