Resumo: This presentation has two parts: (i) the first part provides an overview of recent activities in the U.S. to develop clean hydrogen as an effective decarbonization tool and (ii) the second part of the presentation summarizes the R&D work at the University of California San Diego (UCSD) to develop a superior-performance, high-durability and low-cost solid oxide cell technology for production and use of hydrogen. In the U.S., the U.S. Department of Energy (DOE) has recently produced a National Clean Hydrogen Strategy and Roadmap for facilitating large-scale production processing, delivery, storage, and use of clean hydrogen. The Department has significantly increased support and funding in clean hydrogen areas, especially clean hydrogen electrolysis, has developed the Hydrogen Energy Earthshot goal (”1 1 1”: $1 per 1 kilogram in one decade) and has planned to establish Regional Clean Hydrogen Hubs around the country. At UCSD, the effort on solid oxide cell technology has focused on the development of electrolysis cells (SOECs) for hydrogen production and fuel cells (SOFCs) for power generation. This effort aims at addressing several technological issues in current SOEC/SOFC design, engineering, manufacturing, and operation and developing advanced innovative concepts. Selected results of this R&D work at UCSD on SOEC/SOFC technology will be presented.