Optimization of Bimetallic Nanoparticle Structure for Water and Energy Applications

Sustainability in water treatment and energy conversion processes requires materials that are designed to be high‐performance and durable yet cost‐effective. Increasingly, there is a need for novel, advanced materials that are able to address current and future challenges in the fields of water and energy. These challenges include better removal of recalcitrant water contaminants and the development of technologies that use and convert energy more efficiently. There continues to be an opportunity to use nanostructured and nanosized particles to simultaneously address the need for improved selectivity, activity, and stability in reactive environments. Our research interests in this area focus on the development of bimetallic nanoparticles for electrocatalysis and reactive water treatment applications. We aim to control and optimize nanoparticle formation through the use of two specific ligand families: phosphonate chelators and synthetic, metal‐specific peptides. We develop nanoparticle materials for specific electrochemical or chemical reactions through variation of bimetallic composition, morphological structure, extent of oxide/oxyhydroxide phases, and ligand concentration and molecular structure. We also work to develop structure‐function relationships by correlating performance metrics to high energy x‐ray characterization and microscopy data. In this seminar, I will discuss some of our on‐going work on two different bimetallic systems: phosphonate‐stabilized FeNi nanoparticles and peptide‐stabilized PdAu nanoparticles. Thus far, we have seen that through simple changes in synthesis parameters, we are able to optimize the FeNi nanoparticle material for methanol electrooxidation, nitrogen electroreduction to ammonia, and degradation of a textile dye water contaminant. Previous work on peptide‐stabilized Pd nanoparticles is now being extended to the PdAu system, where electrochemical performance appears to be influenced by the peptide sequence used during particle synthesis.

For further information please contact Samuel Stavis, 301-975-2844, samuel.stavis [at] nist.gov (samuel[dot]stavis[at]nist[dot]gov)