Switched on: Chemistry major finds passion in creating microscopic circuits

Josh Walker '20 didn’t come to Longwood thinking about molecular electronics, but that’s all he’s doing these days. The chemistry major, a rising senior, is spending the summer working with Dr. Ben Topham, assistant professor of chemistry, on a long-running project aimed at creating electronic circuits using single molecules in place of regular components like diodes and resistors. Walker is part of the PRISM summer research initiative—highly competitive, paid summer research work with a Longwood professor.

We caught up with Walker to find out more about the circuitry he’s investigating.

How did you get involved in PRISM?

I enjoy research in general—I did an honors enhancement for a class and really enjoyed that experience—but wanted to do more research in an environment where I could focus on just that one project. I heard about PRISM and explored different projects, but took special note of Dr. Topham’s because single-molecule electronics is so interesting.

Tell us about the project.

In electronic devices, there are all sorts of components like switches and diodes. We are looking at designing single molecules to act like those components we are familiar with, in essence creating extraordinarily small electronic circuits.

The way we do that is by building molecules on a computer and then running them through testing software that can predict how they would perform when connected to electrodes.

Where do these molecules come from?

Well, we could just invent them ourselves but we do a lot of research into ones other chemists have designed, and our goal is to enhance them as much as we can to make the best-performing one. We do a lot of brainstorming and testing of different variations. It’s a constant process of building molecules and looking at data.

Have you had any success?

We have found some trends in the switches we’ve made, and we’ve added substituents of other groups of atoms around the molecules that have different properties, so we’ve been able to find some trends that give us a good direction to explore.

Do you have any career goals or plans after graduation?

I’m not totally sure yet—trying to keep my options open. I’m looking at grad schools but will also apply to industry jobs. I’m interested in molecular electronics, food chemistry and pharmaceuticals.

Onto the important questions: What is your favorite thing to do in Farmville?

I like to fish, and there are good places for that around the area.

Favorite thing to eat at D-Hall?

Chicken patties, for sure.