Stable Open-Shell Aromatic Oxalic Acid Radical for Efficient Pho-tothermal Conversion

It has been reported that the intrinsic open-shell quinone radical electronic ground state is commonly present in classic narrow bandgap donor-acceptor organic semiconductors. Among them, aromatic inorganic acid radicals are one of the important categories of classical narrow bandgap donor-acceptor type organic semiconductors and display unique physical properties and electronic ground states. Generally, the conjugated planes play a crucial role in stabilizing multi-radical electronic systems. In this paper, we are the first to design, synthesize, and report fully planar graphene-like two-dimensional aromatic oxalic acid radical IDF-O8 based on the aromatic inorganic acid radical system, and study the physical properties of this aromatic high spin pan. In this graphene-like structure, the electron-withdrawing group of ketones can effectively delocalize radical electrons and achieve stability. In addition to exhibiting strong spin signals, the temperature of IDF-O8 reached 147 °C in aggregated state under the irradiation of 808 nm (1.2 W cm-2). This work provides a novel planarized radical design strategy and has great potential in seawater desalination.