title: Using Perovskite Nanoparticles as Halide Reservoirs in Catalysis and as Spectrochemical Probes of Ions in Solution.
abstract: The ability of cesium lead halide (CsPbX3; X = Cl(-), Br(-), I(-)) perovskite nanoparticles (P-NPs) to participate in halide exchange reactions, to catalyze Finkelstein organohalide substitution reactions, and to colorimetrically monitor chemical reactions and detect anions in real time is described. With the use of tetraoctylammonium halide salts as a starting point, halide exchange with the P-NPs was performed to calibrate reactivity, stability, and extent of ion exchange. The exchange of CsPbI3 with Cl(-) or Br(-) causes a significant blue-shift in absorption and photoluminescence, whereas reacting I(-) with CsPbBr3 causes a red-shift of similar magnitudes. With the high local halide concentrations and the facile nature of halide exchange in mind, we then explored the ability of P-NPs to catalyze organohalide exchange in Finkelstein like reactions. Results indicate that the P-NPs serve as excellent halide reservoirs for substitution of organohalides in nonpolar media, leading to not only different organohalide products, but also a complementary color change over the course of the reaction, which can be used to monitor kinetics in a precise manner. The merits of using P-NP as spectrochemical probes for real time assaying is then expanded to other anions which can react with, or result in unique, classes of perovskites.
authors.affiliation: Department of Chemistry, Syracuse University , Syracuse, New York 13244, United States.
authors.forename: Tennyson L
authors.initials: TL
authors.lastname: Doane
authors.affiliation: Department of Chemistry, Syracuse University , Syracuse, New York 13244, United States.
authors.forename: Kayla L
authors.initials: KL
authors.lastname: Ryan
authors.affiliation: Department of Chemistry, Syracuse University , Syracuse, New York 13244, United States.
authors.forename: Laxmikant
authors.initials: L
authors.lastname: Pathade
authors.affiliation: Department of Chemistry, Syracuse University , Syracuse, New York 13244, United States.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Cruz
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973, United States.
authors.forename: Huidong
authors.initials: H
authors.lastname: Zang
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973, United States.
authors.forename: Mircea
authors.initials: M
authors.lastname: Cotlet
authors.affiliation: Department of Chemistry, Syracuse University , Syracuse, New York 13244, United States.
authors.forename: Mathew M
authors.initials: MM
authors.lastname: Maye
keywords: CsPbX3; Finkelstein; anion exchange; chemical assay; colorimetric; lead halide; nano; perovskite; spectrochemical