Matt Law, Ph.D. | FUN 2025

Matt Law, Ph.D.

Assistant Professor, Department of Chemistry

University of California, Irvine

Speech Title:

Developing quantum dot solids for next-generation photovoltaics

Abstract:

Colloidal semiconductor quantum dots (QDs) are attractive building blocks for next-generation solar photovoltaics (PV). In this talk, I will highlight recent progress in understanding, improving, and controlling charge transport within mesoscale assemblies of lead salt QDs, with the aim of achieving simultaneously efficient carrier multiplication (CM) and charge extraction to produce record-efficiency single-junction PV. I begin by discussing QD film fabrication, charge transport physics, and evidence that the carrier diffusion length is short and limited by electronic states in the QD band gap. Efforts to improve carrier mobility by enhancing inter-dot electronic coupling, passivating surface states, and implementing surface doping will be presented. Engineering the inter-QD matrix to produce QD/inorganic or QD/organic nanocomposites is introduced as a powerful way to optimize coupling, remove surface states, eliminate hysteretic charge trapping and ion motion, and achieve long-term environmental stability for high-performance, robust QD films that feature good CM efficiency. Prospects for overcoming the diffusion-limited recombination that seems to constrain diffusion length are discussed, as well as the possibility of band-like transport through extended electronic states and the importance of utilizing QD superlattices for this purpose.

Bio:

Professor Matt Law joined the Chemistry Department at the University of California, Irvine in 2008. He received his Ph.D. in Chemistry from the UC Berkeley in 2005, where he investigated the synthesis, properties, and device applications of oxide nanowires under the direction of Peidong Yang. For this work, he was named a 2005 Young Investigator by the Division of Inorganic Chemistry of the American Chemical Society and was awarded the 2006 IUPAC Prize for Young Chemists. His postdoctoral research with Arthur Nozik at the National Renewable Energy Laboratory focused on the development of quantum dot solar cells and photoelectrochemical water splitting devices. Matt’s research interests are driven by the challenges of energy conversion and storage and the conservation of global biodiversity. His research group focuses on the development of new materials and devices for solar energy conversion, including nanostructured solar cells, earth-abundant thin-film photovoltaics, and solar fuels production. Matt received the DOE Early Career Award in 2010 and was named a Sloan Fellow, a Distinguished Assistant Professor for Research at UCI, a UCI Chancellor’s Fellow, and a Thomson Reuters Highly Cited Researcher (2002 – 2012). He has published ~50 papers (cited more than 16,000 times) and holds eight patents in the areas of nanoscience and photovoltaics.