New method for effective production of hydrogen peroxide for fuel cells

Scientists have used sunlight to turn seawater (H2O) into hydrogen peroxide (H2O2), which can then be used in fuel cells to generate electricity. It is the first photocatalytic method of H2O2 production that achieves a high enough efficiency so that the H2O2 can be used in a fuel cell.

In the new study, the researchers led by Shunichi Fukuzumi at Osaka University, developed a new photoelectrochemical cell, which is basically a solar cell that produces H2O2. When sunlight illuminates the photocatalyst, the photocatalyst absorbs photons and uses the energy to initiate chemical reactions (seawater oxidation and the reduction of O2) in a way that ultimately produces H2O2.

After illuminating the cell for 24 hours, the concentration of H2O2 in the seawater reached about 48 mM, which greatly exceeds previous reported values of about 2 mM in pure water. Investigating the reason for this big difference, the researchers found that the negatively charged chlorine in seawater is mainly responsible for enhancing the photocatalytic activity and yielding the higher concentration.

Overall, the system has a total solar-to-electricity efficiency of 0.28%. (The photocatalytic production of H2O2 from seawater has an efficiency of 0.55%, and the fuel cell has an efficiency of 50%.)

Read more at Phys.org

Image Credit: Adobe Stock

-jk-