Metalloligand Nickel Bis(Dithiolene) Based Metal–Organic Frameworks for Efficient Photocurrent and Photothermal Conversion

Nickel bis (dithiolene) complexes are strong sunlight absorbers with high thermal- and photostability and are nonluminescent, resulting in remarkable photothermal properties. Nevertheless, nickel-bis (dithiolene) -based metal–organic frameworks (MOFs) have rarely been reported as photothermal and photocurrent agents. Herein, nickel-bis (dithiolene-dibenzoic acid) Ni (C2S2 (C6H4COOH) 2) 2, as a new functional redox-reversible "non-innocent" metalloligand, was innovatively assembled into two MOFs, Zn2Ni (C2S2 (C6H4COO) 2) 2 (H2O) 2·2DMF and Cd2Ni (C2S2 (C6H4COO) 2) 2 (H2O) 2·2DMF (1 and 2, DMF = N, N-dimethylformamide). Under one-sun illumination (0. 1 W cm–2, 300–2500 nm), the temperature of the MOFs sharply increased to 69. 6 and 69. 3 °C from room temperature in 300 s, concomitant with induced photocurrents of 7. 0 and 6. 5 μA for 1 and 2. The considerable performance is due to charge transfer, as revealed by cyclic voltammetry (CV) and solid-state UV/vis–NIR spectroscopy. This study not only provides insights into the development of photothermal and photoconductivity materials but also paves the way for designing functional materials with appealing applications.