Research

Molecular hydrogen is a clean, carbon-free energy carrier. To generate hydrogen in an inexpensive way, we utilize polymer-supported metal complexes which are composed of earth-abundant elements and soluble in neutral water. The goal of the project is to split water into hydrogen electrochemically at fast rates and with low energy requirements (overpotential) in buffered neutral aqueous solutions.

Metallopolymers' field sits at the interface of organic chemistry, polymer chemistry, and organometallics. Polymers are grown from a metal complex decorated with one or two initiator sites using controlled radical polymerization (CRP) techniques such as atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain transfer (RAFT) polymerization. Metal complexes possess unique functions such as catalysis, and polymeric "arms" show complementary action and provide crucial properties to the system such as solubility and processability.

[2Fe-2S] metal complex designed for electrocatalytic hydrogen evolution has the same motif as in the active site of the [FeFe]- hydrogenase enzyme. These catalytically active complexes are functionalized with initiators for polymerization.

Elemental sulfur is a byproduct of the hydrodesulfurization process in the petroleum refining industry which generates underutilized sulfur mountains. We synthesized amine functional sulfur prepolymers which were then reacted with an epoxy-functional POSS cage complex to prepare crosslinked sulfur polymers.

There is significant interest in the use of semiconductor nanocrystals as photocatalysts for the production of fuels (e.g., H₂) from sunlight, the primary active layer in photovoltaic, etc. II-VI semiconductor materials, such as CdSe have been the most extensively studied because they enable composition- and size-dependent tunability of absorption and emission properties in the broad range of the electromagnetic spectrum. In this project, II-VI semiconductor nanocrystals were synthesized starting from the simplest form (i.e., quantum dots) followed by more complex heterostructured motifs (e.g., nanorods, metal-tipped nanorods).

Silica aerogel project is my "old but gold" project for thermal insulation systems. Silica aerogels are light, low density, and porous materials and have low thermal conductivity (<20 mW/m.K). Aerogels are made via sol-gel chemistry and subsequent supercritical CO₂ drying to retain the porous structure. These techniques enable aerogels to have unique properties including low thermal conductivity. One of the major challenges in this project has been improving optical and mechanical properties without sacrificing thermal properties.

My presentation at Virtual Georgia Tech Postdoc Talk Competition in Polymer Research (2021). Link

A recorded talk for 24th Annual GC&E Virtual Conference on "Biomimetic Metallopolymers for Electrocatalytic Hydrogen Generation in Water".