An ultrastable Zr-MOF for fast capture and highly luminescence detection of Cr2O72− simultaneously in an aqueous phase

Abstract

Herein, using the modulator synthesis approach, a zirconium-based metal–organic framework (Zr-MOF), [Zr₆O₄(OH)₄L₄(H₂O)₂(HCOO)₄]·9DMF·12H₂O (JLU-MOF50, L = H₂MDCPB = 5′-methyl-[1,1′,3′,1′′-terphenyl]-4,4′′-dicarboxylic acid, DMF = N,N-dimethylformamide), with pcu topology was successfully synthesized and structurally characterized. JLU-MOF50 exhibits excellent chemical stability in both acidic and alkaline aqueous solutions. Due to the missing linker sites, high porosity (BET surface area of 1101 m² g⁻¹), and excellent luminescence property, JLU-MOF50 possesses dual functionalities, which exhibits not only a commendable trapping capacity (92 mg g⁻¹) and an adsorption rate (32.5 mg g⁻¹ min⁻¹), but also high detection sensitivity and selectivity for Cr₂O₇²⁻ in an aqueous phase. It is worth mentioning that the K_SV value of JLU-MOF50 towards Cr₂O₇²⁻ can reach up to 4.99 × 10⁴ M⁻¹, which is one of the highest values reported to date for MOF materials. Based on the aforementioned properties, JLU-MOF50 is a good candidate for fast capture and highly luminescence detection of Cr₂O₇²⁻ simultaneously in an aqueous phase.