Comprehensive and Innovative Experimental Study on Determination of Ferrous Ion by Spectrophotometry with a Novel 1,10-Phenanthroline Schiff Base Chromogenic Reagent
QI Dong-Lai, ZHAO Zhuo**
School of Chemistry,Tiangong University,Tianjin 300387,China
Abstract This study conducted comprehensive innovation research on the traditional analytical chemistry experiment of ferrous ion(Fe2+) determination by spectrophotometry using 1,10-phenanthroline as chromogenic agent for undergraduates.A novel Schiff base chromogenic reagent,3-(1,10-phenanthroline-5-imino)-4-hydroxybenzoic acid(abbreviated as PIHBA) was synthesized,and its chromogenic performance for Fe2+ was tested.Experimental results showed that PIHBA exhibited superior chromogenic capability compared to 1,10-phenanthroline,rapidly forming stable orange-red complexes with Fe2+ at room temperature.The maximum absorption wavelength of the complex caused a red shift to 520 nm and the molar absorption coefficient increased to 1.3×104 L·mol-1·cm-1.Furthermore,the results of the control and identification experiments demonstrated that PIHBA had high selectivity and sensitivity to Fe2+ with a detection limit of 0.045 mg/L.This research project deeply integrates organic chemistry with analytical chemistry,enhancing the effectiveness of experimental teaching.The innovative study not only boosts students’ interest in theoretical knowledge and laboratory practice,but also deepens their understanding of the intrinsic connections between material structures and chemical properties,thereby fostering innovative thinking.
QI Dong-Lai, ZHAO Zhuo. Comprehensive and Innovative Experimental Study on Determination of Ferrous Ion by Spectrophotometry with a Novel 1,10-Phenanthroline Schiff Base Chromogenic Reagent[J]. Chinese Journal of Chemical Education, 2026, 47(16): 57-64.
