Batteries for Producing Hydrogen Peroxide from Air

Researchers at the Indian Institute of Science (IISc) have made a significant breakthrough in the production of hydrogen peroxide (H2O2), a versatile chemical compound widely used in various industries. Traditionally, industrial production of H2O2 has been costly and energy-intensive due to the use of rare and precious metal catalysts. However, the team at IISc has developed an innovative onsite production method that not only generates H2O2 but also has the capability to degrade harmful industrial pollutants such as toxic dyes.

The key to this new approach lies in the utilization of a zinc-air battery, where the process of oxygen reduction leads to the formation of H2O2. Professor Aninda J Bhattacharyya, from the Interdisciplinary Centre for Energy Research (ICER) and Solid State and Structural Chemistry Unit (SSCU) at IISc, highlights the advantages of using zinc as the primary element in this battery. Zinc is abundant, cost-effective, and readily available in India, making it a sustainable choice for this innovative production strategy.

In a metal-air battery configuration, zinc serves as the anode while ambient air acts as the cathode. During the discharge of the battery, oxygen from the surrounding air undergoes reduction at the cathode, resulting in the production of H2O2. This electrochemical process offers a controlled method for generating H2O2, as explained by Bhattacharyya, who emphasizes the importance of regulating the oxygen reduction reaction to prevent the formation of water instead of H2O2.

The team has successfully achieved this control by employing metal-free catalysts based on carbon, as mentioned by Asutosh Behera, the first author of the study and a PhD student at SSCU. While inexpensive catalysts typically favor the formation of water over H2O2, the researchers have introduced specific chemical modifications to enhance the selectivity towards H2O2 production. By incorporating oxygen functional groups into the catalysts, the reaction pathway can be directed towards the desired outcome of H2O2 synthesis.

One of the key advantages of this novel approach is the direct production of H2O2 using a battery system, eliminating the need for additional steps or processes. Bhattacharyya highlights the simplicity of the method, stating that by adjusting the voltage levels, the battery can be tailored to exclusively generate H2O2. This innovative technology not only offers a more sustainable and cost-effective method for H2O2 production but also holds promise for addressing environmental challenges by facilitating the degradation of industrial pollutants.