Two New Fellows to Help Guide NREL Research

The Energy Department’s National Renewable Energy Laboratory (NREL) recently named Dr. Maria Ghirardi and Dr. Angelo Mascarenhas to its Research Fellows Council, the laboratory’s top advisory council comprised of internationally recognized NREL scientists and engineers.

Along with the 10 current members of the Research Fellows Council, Dr. Ghirardi and Dr. Mascarenhas will advise NREL executive management on the strategic direction of science and technology research at the laboratory.

Dr. Ghirardi is a principal scientist at NREL, a research associate professor at the Colorado School of Mines, and a Renewable and Sustainable Energy Institute (RASEI) Fellow.

She is involved in both basic and applied research and has had extensive experience working with photosynthetic organisms. Dr. Ghirardi’s work at NREL involves photobiological hydrogen production and covers metabolic, biochemical, and genetic aspects of algal metabolism. She co-discovered a sulfur-deprivation process, which allows sustained hydrogen production from algae. In addition, Dr. Ghirardi’s team identified three enzymes required for the assembly of [FeFe]-hydrogenases, which led to the development of a bacterial system for the production of large quantities of active algal hydrogenase enzyme, a major breakthrough in research.

Her team also initiated the use of molecular dynamics to create computational simulations of oxygen and hydrogen gas diffusion through the hydrogenase enzyme, which led to the identification of two access pathways for oxygen to the catalytic site of the enzyme. This approach is now extensively used by groups in Europe to engineer oxygen tolerance into [NiFe]-hydrogenases. In collaboration with Dr. Matt Wecker from Genebiologics, Dr. Ghirardi developed a new selection method to isolate algal mutants with improved hydrogen producing capability, and made improvements in hydrogen photoproduction resulting from both physical and genetic manipulations.

Dr. Ghirardi also reported that algae can produce dramatically more hydrogen via the sun when the gas-phase to liquid-phase volume ratio in a bioreactor is increased. The observation helped bump up algae as major players in the search for the best alternative fuel of the future. Recently, her group has focused on the development of hybrid systems involving a synthetic charge-separation device coupled to biological hydrogenase enzymes. This project is currently led by her colleague, NREL senior scientist Paul King.

“I am honored to be selected as a NREL fellow, and my main objective as a fellow is to bring more visibility to my group’s research within NREL and DOE,” Dr. Ghirardi said. “I believe that photobiology has the potential to lead to the development of optimized organisms to produce a range of biofuels and to provide new insights regarding the basic processes of photosynthesis that can serve as the model for development of photochemical processes.”

Dr. Mascarenhas, group leader of the Material Sciences Group, counts among his career highlights finding a new way to produce a vibrant green color – essential to formulating a cost-effective, energy-efficient white LED light that could revolutionize indoor lighting in the years to come. Faced with the same roadblocks stymying other labs, Dr. Mascarenhas followed a different path – flipping over the formula NREL had used to make multi-junction solar cells. Dr. Mascarenhas is a recognized leader in the characterization and physics of semiconductors, particularly those with interesting optoelectronic properties. He has provided fundamental insights on the electronic properties of semiconductor alloys for potential use in photovoltaics and solid-state lighting.

His research on the consequences of spontaneous lateral composition modulation on the optical properties of short-period superlattices helped pioneer this novel field. Recently, Dr. Mascarenhas introduced the study of dilute bismide alloys as an analogous counterpart of dilute nitride alloys, which has significant implications for photovoltaics as well as the field of spintronics – an emerging field of nanoscale electronics involving the detection and manipulation of electron spin. He also helped build and staff NREL’s state-of-the-art, multimillion dollar spectroscopy lab.

“Being named an NREL fellow is a privilege,” Dr. Mascarenhas said. “I hope the recognition will help steer and guide the research direction of the next generation of NREL scientists.” Dr. Mascarenhas has authored more than 280 scientific publications, has three issued patents with seven more filed, and is a RASEI Fellow.