CEMS research under the Energy theme is very broad, spanning both conventional and renewable energy resources, and device-level to systems-levels efficiency optimization. Advanced semiconductors for solar cells are actively pursued, as are critical atom-efficient pathways for hydrocarbon (e.g. natural gas) utilization, and electrochemical approaches to convert electricity to fuels. Robust thermal barrier materials for combustion engines is another emphasis. Process systems research focuses on unique, multiplexed opportunities afforded by the electrification of the chemical industry. Sub-categories under the Energy theme include: