Innovative selective solar absorber for high vacuum flat panel Daniela De Luca, Antonio Caldarelli, Eliana Gaudino, Paolo Strazzullo, Marilena Musto, Umar Farooq, Emiliano Di Gennaro and Roberto Russo EPJ Web Conf., 287 (2023) 05017 Published online: 18 October 2023 DOI: 10.1051/epjconf/202328705017