We propose a general approach for the achievement of optical sensors, where ammonia can be rapidly identified and detected through visible fluorescence changes. Here, a tetraphenylethylene derivative with carboxyl groups named TPE-2CA (4,4ʹ-(1,2-Diphenylethene-1,2-diyl) dibenzoyl acid) was applied in the sensor. The AIE (aggregation-induced emission) property of tetraphenylethylene structure provides the samples with excellent luminescent performance in aggregated state. The reaction between carboxyl groups and ammonia causes the shifts on luminescence spectra of the samples. Consequently,...