In order to investigate photothermal response of the molecular heaters under the light irradiation, 0.30 mmol of CoCl2•6H2O or 0.14 mmol of DHBDC were dissolved separately in 5 mL of DMF, followed by withdrawing of 1 mL solution and heated photothermally under 520 nm or 660 nm light for 30 min (maximum temperature was set to 150 °C). Next, for the stability test, either the molecular heaters or purified Co-DHBDC synthesized through conventional heating were put under the photothermal heating conditions in presence of 520 nm or 660 nm light with minimum and maximum temperature set between 100-120 °C, and the reaction was monitored for 1-2 h.