▎ 摘　　要

NOVELTY - A black body absorbing coating comprises an infrared reflective layer, a barrier layer, a graphene material absorption layer, an auxiliary absorption layer, and an anti-reflection layer, which are arranged in the opposite direction of incidence of light. The barrier layer is nickel oxide. The auxiliary absorption layer is chromium oxide. USE - Black body absorbing coating for photothermal conversion component used in solar water heater (all claimed). ADVANTAGE - The black body absorbing coating has wider absorption band, high light utilization rate, photothermal conversion efficiency, and adhesive force, and excellent smoke resistance. The photothermal conversion component has high efficiency due to the presence of the black body absorbing coating. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for photothermal conversion component, which comprises a heat conducting plate, the black body absorbing coating layer coated on the heat conducting plate, and a liquid heat exchange medium arranged under the heat conducting plate.