Visual sensing Ni2+ in real samples with test paper based on a new dinuclear terbium complex

Abstract

Nickel (Ni) is an essential metal element widely used in industrial production and daily life; however, long-term human exposure to nickel may lead to skin allergies, damage to genetic material, and even the possible induction of cancer. Therefore, the development of an accurate, rapid, and convenient method for detecting Ni²⁺ is of importance. In this work, rare earth dinuclear complex Tb-TFBA is designed and its precise structure is analyzed by single crystal analysis. Experimental results show that Tb-TFBA possesses strong anti-interference capabilities, short response time (20 s), and an extremely low detection limit (LOD = 0.1 nM); the LOD is significantly lower than the minimum detection value of the national safety standards for drinking water (20 nM, GB 5749-2022). Furthermore, a portable sensing device of test paper is developed based on Tb-TFBA. The device achieves specific visual detection of Ni²⁺ in real samples, which is portable and easy to use in daily life.