Target design and synthesis of three naphthyl-functionalized Copper(II) coordination compounds for their photothermal properties

Abstract

In order to achieve a light-harvesting system with excellent photo-thermal conversion property, three naphthyl(NT)-functionalized Copper(II) coordination compounds have been designed and isolated. They are characterized by IR, Powder XRD, UV, and TGA. Single-crystal X-ray structural analysis reveals that {[Cu4(bpy)4(1-NTAA)5](BF4)3∙3(CH3OH)∙H2O}∞ (1) has 1D chain structure, {[Cu2(1-NTAA)4(CH3CN)2]∙2(CH3CN)} (2) and {[Cu2(2-NTA)4(CH3CN)2]∙2.5(CH3CN)} (3) have similar paddle-wheel structures. Utilizing the introduction of NT-groups into copper(II) centers, all three compounds exhibit good solid-state optical absorption in a nearly full solar spectral region. The coordination polymer 1 exhibits the quickest temperature rising (nearly 2 ℃/min from the very beginning), the highest temperature increment (12 ℃) and equilibrium temperature (40 ℃) over the other two compounds in the photothermal conversion experiments. Those results point out the direction of molecular design for enhancing photothermal conversion performance.