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Updated: Oct 3, 2026

Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
Discrimination of methylammonium from organic ammonium ions using ion-selective electrodes based on
1Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Okayama 700-8530, Japan. katsu@pheasant.pharm.okayama-u.ac.jp
Abstract:
Calix[4]-bis-2,3-naphtho-crown-6 can be used to discriminate between methylammonium and other organic ammonium ions. An electrode based on this ionophore, potassium tetrakis(p-chlorophenyl)borate (20 mol% relative to the ionophore) as an ionic additive and bis(2-ethylhexyl) sebacate as a solvent mediator in a poly(vinyl chloride) membrane matrix, displayed higher selectivity for methylammonium than for various other organic ammonium ions. However, there was considerable interference by inorganic cations, especially Cs+. Similar calix[4]arene-crown-6 conjugates, such as calix[4]-bis-1,2-benzo-crown-6, calix[4]-bis-crown-6, 1,3-dioctyloxy-calix[4]arene-crown-6, 1,3-diisopropoxy-calix[4]arene-crown-6 and 1,3-dimethoxy-calix[4]arene-crown-6 were less effective in discriminating methylammonium.
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