(6u) Imitating Nature’s Approach: Molecular Engineering of Organic Materials for Energy and Sensing

My research interests and area of expertise sit at the interface of soft materials science and device fabrication for applications in energy, human health, and environmental sustainability. While conventional electronic devices are composed of hard materials, the pliability and chemical reactivity of organic materials may enable game-changing solutions to pressing scientific challenges. Here, I present two examples of molecular engineering of organic materials for (1) mechanically robust organic photovoltaics (OPVs) and (2) bio-inspired selective chemical sensors.

First, I will discuss the relationships between mechanical deformability and charge transport in polymeric systems, and the rational design principles that afford intrinsically stretchable OPVs. Organic photovoltaics hold promises to produce devices with performance approaching that of silicon-based electronics, but with the mechanical stability of conventional plastics. However, obtaining this “plastic” deformability and high photovoltaic performance has proven challenging. In addition, the mechanical fragility of many high performing conjugated polymers limits their applicability for large-area, low-cost, and printable devices. Using mechanical, spectroscopic, photovoltaic device-based measurement, I demonstrate the impact of molecular structure and solid-state packing on bulk mechanical properties, allowing for the co-optimization of OPVs towards the “best of both worlds.”

Second, I will also discuss the designs of two novel chemical sensors—based on single-walled carbon nanotubes (SWCNTs) or complex liquid colloids—that translate molecular and biological recognition into sensory systems for environmental and health monitoring. Although selectivity underpins the utility of any sensing platform, obtaining a selective and practical sensor is often elusive. To address this challenge, I integrate bio-inspired molecular receptors into the sensing platforms to impart high selectivity and responsiveness. Specifically, a heme-inspired iron porphyrin provides controllable sensitivity towards carbon monoxide in SWCNT-based gas sensors, and carbohydrate-lectin binding allows for the detection of Escherichia coli bacteria using complex emulsions. These nature-inspired examples serve as an important step in demonstrating the possibility of translating chemical principles to practical devices.

Teaching Interests:

I believe that the success of the students is the most important accomplishment of the teacher. Throughout my studies, I have had impactful mentors whose goals were to guide me toward the best possible path. I am dedicated to pay this debt forward to my students and future mentees.

Between my undergraduate and graduate trainings in chemical engineering at UC Berkeley and UC San Diego, my research in polymeric soft materials, and my postdoctoral training at MIT, I am confident that I can teach anything within the chemical engineering curriculum. I have a particular passion for the core courses (fluid dynamics, heat and mass transfer, and thermodynamics) as well as courses related to polymeric materials and chemical synthesis. I have taught a graduate level course in intermolecular and surface forces that sits at the interface of my research interest and my formal training in chemical engineering. In addition, I served as a TA for the undergraduate introductory class to polymer science.

Mentorship is a critical facet of my educational mission. As a graduate student at UC San Diego, I have mentored 9 undergraduate students, all of whom became co-authors on at least one papers. At MIT, I am currently the primary mentor of 3 graduate students and have mentored 3 other who have graduated with their Ph.D. I aim to continue mentoring students as a professor.

Selected Publications