Development of a Robust Polymer Electrolyte Membrane Electrolyzer for H2 Synthesis
Abstract
The production of hydrogen (H2) as an enabling fuel from abundant sources such as sea and/or fresh water has become the priority for reduction of long-term operational demands. Hydrogen fuel is unique because it has energy density of 120 MJ/kg (34 kWh/kg), which is three times greater than diesel or gasoline. The standard commercial method of hydrogen production involves the utilization of polymer electrolyte membrane (PEM) electrolyzers in the membrane electrode assemblies (MEAs). The #gold standard# platinum black (Pt/C) is used as a cathode catalyst, which is very expensive, thus the clean synthesis of hydrogen is not commercially cost efficient. The hydrogen evolution reaction (HER) is the cathodic reaction in electrochemical water splitting where highly efficient and ultra-stable electrocatalysts are crucial to increase the rate of the reaction and the long-term stability of the cathode. A potential design solution is to construct an innovative PEM electrolyzer using earth abundant metals in the form of nanocrystals as cathode catalysts with equivalent or better catalytic efficiency and durability than that available with Pt-based hydrogen production. An overarching goal of this grant is to synthesize and characterize unique, photon-absorbing semiconductor nanocrystals (NCs) that can be integrated into a PEM electrolyzer as a photocathode to facilitate cost effective and scalable hydrogen production from seawater. We propose to use plasmonically-active chalcogenide- doped metal oxide NCs, which are capable of absorbing abundant low energy solar photonsto enhance their HER kinetics. The proposed NCs will be synthesized using earth abundant metals, therefore the hydrogen production will be highly cost efficient relative to Pt. The research objectives include high purity hydrogen production by water electrolysis under solar light enhancement to achieve the following figures of merit: (1) >600 g hydrogen produced in 24 hours, (2) an ~50% MEA efficiency at >2.0 A/cm2 current density, (3) operating capability under high humidity and temperature conditions, and (4) generationof hydrogen from both sea and fresh water. Thus, a new frontier in scientific research and development including large-scale production of hydrogen from renewable sources will be opened through the selection and fabrication of a previously unknown cathode-containing, non-precious metal electrocatalyst. This opening will unfold the process of construction of a lab-scale PEM electrolyzer prototype for hydrogen electrosynthesis. Therefore, as a part of the Naval Expeditionary Energy (Code 331) mission, our research will aim to fulfill the efforts to de-risk and make resilient future energy ecosystems through high quality hydrogen production.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 13, 2024
- Source ID
- N000142412387
Entities
People
- Rajesh Sardar
Organizations
- Indiana University
- Office of Naval Research
- United States Navy