CuO could also be a good candidate in solar energy conversion due to many properties: high absorption coefficient, narrow bandgap in the visible region, which is expected to give high conversion efficiency, being nontoxic, stable, good electrical conductance, simple manufacturing process, and so on. A more direct way to convert solar energy to electricity is to use CuO as an absorber in solar cells. The efficiency of solar cells based on CuO is far lower than that of leading chalcogenide systems such as CIS or CIGS. Still, due to its low cost, abundant resource, and simple preparation process, it was shown that the efficiency of only several percent in cells based on CuO is good enough to make commercial solar cells. Unlike its counterpart Cu2O, CuO is used less for solar cells as the achieved efficiency for Cu2O is higher. Several reports on CuO solar cells are rare, but recent results show promising achievements, which shows that further development of CuO nanomaterials-based solar cells has a bright future. Kidowaki et al. Prepared solar cells based on CuO nanoparticles/C60 junction, which provided the efficiency of 1.8 × 10−6%, fill factor of 0.25, of 0.18 × 10−3 mA cm−2 and of 0.04 V. A crystallite size of CuO was determined to be 3.4 nm, and higher crystallinity of CuO would increase the efficiency of the CuO/C60 solar cells. Or more recently, using the solvothermal method, Chandrasekaran prepared CuO nanoparticles using the solvothermal method and used the product to make a solar cell with an efficiency of 0.863%, compared with other reported values. Up to now, the record efficiency of solar cells based on copper oxide is about 2%, while the theoretical value is about 20%, so an efficiency of several percent is achievable. If you are looking for high quality, high purity, and cost-effective copper oxide, or if you require the latest price, please email contact mis-asia.