Indexed by:期刊论文

Date of Publication:2019-06-01

Journal:CHEMICAL RESEARCH IN CHINESE UNIVERSITIES

Included Journals:SCIE

Volume:35

Issue:3

Page Number:370-376

ISSN No.:1005-9040

Key Words:Photoelectrochemical probe; Ru(II) bipyridyl complex; Hg2+ detection; Nanocomposite

Abstract:A biomolecule-free photoelectrochemical(PEC) probe(denoted as Ru-1) was designed, synthesized and coupled with TiO2 nanoparticles(NPs) for the highly sensitive and selective PEC detection of Hg2+, a model analyte with hypertoxicity to both human health and ecosystem. The probe Ru-1 was designed with Ru(II) bipyridyl complex as the chromophore, thiocyanate ligand as the recognition unit, and carboxylate group as the linkage site to connect Ru-1 to TiO2 nanoparticles. Under irradiation, Ru-1 shows strong affinity to TiO2 and good photophysical properties of strong visible light absorption, slow electron-hole(e-h(+)) recombination, and fast photoelectron injection to TiO2 nanoparticles via the pi-bridge of 4-(2,2'-bipyridin)-4-yl-thiophene moiety. However, the specific coordination of Hg2+ with Ru-1 via the thiol moiety in the thiocyanate enlarges the band gap of the complex and reduces the photocurrent significantly. The synergistic interaction between TiO2 nanoparticles and the Ru-1 complex led to a selective PEC sensing strategy for Hg2+ detection. Detectable linear ranges from 10(-12) g/mL to 10(-7) g/mL and from 10(-7) g/mL to 10(-3) g/mL were obtained without the interference from possibly co-existed metal ions. The good analytical performances indicate the chemical probe based biomolecule-free PEC platform may offer a new route for the detection of biologically and environmentally important small molecules.