Two Terbium Metal–Organic Frameworks Showing Fluorescence Sensing and Proton Conductivity
Tai-Lin Ren, Miaomiao Wang, Tian-Zheng Xiong, Xiao-Nuan Zhang, Yan Peng, He‐Rui Wen, Sui‐Jun Liu
Abstract
Two new terbium-based metal–organic frameworks, {[Tb(ADBA)(CH 3 COO)(H 2 O)]·H 2 O} n ( MOF 1 ) and [Tb(ADBA)(HCOO)(DMF)] n ( MOF 2 ) (H 2 ADBA = 4,4′-(9,10-anthracenediyl) benzoic acid), were synthesized by the solvothermal method. Structural analysis indicates that the Tb III ions in MOFs 1 and 2 are coordinated to acetic and formic acids, respectively, leading to differences in the structures. Fluorescence measurements show that both MOFs 1 and 2 are fluorescence sensors for Al 3+ and Ga 3+ with fluorescence enhancement and a blue shift. The detection limits of MOF 1 are 0.067 μM for Al 3+ and 0.093 μM for Ga 3+, and the detection limits of MOF 2 are 0.064 for Al 3+ and 0.086 μM for Ga 3+ . The proton conductivity measurements of MOFs 1 and 2 indicate that the proton conductivities of MOFs 1 and 2 increase in resistance with increasing humidity. MOF 1 is more sensitive to humidity with a maximum conductivity of 1.07 × 10 –5 S·cm –1 under 40 °C and 98% RH. Therefore, MOFs 1 and 2 are potential multifunctional MOF materials.