The colorimetric and coulometric dual-mode sensing strategies based on electrochromic Prussian blue (PB) device are proposed for reading out the potentiometric responses of the solid-contact ion-selective electrodes (ISEs). The mechanism is that the transformation between the bleached state and the colored state for the PB-based electrochromic device is modulated by using the solid-contact Ca²⁺-ISE with changing the ion activities under the control of a constant potential, and a transient current related to the oxidation-reduction reaction of PB is also obtained. Results show that the concentration range of 1.0 × 10⁻⁶-1.0 × 10⁻² Ca²⁺ can be qualitatively and semi-quantitatively detected through observing the color change via the naked eye or analyzing the red-green-blue (RGB) values by a smartphone and the corresponding integrated charges of the PB-based electrochromic device under the control of the applied potential. These proposed readout strategies are not only free from the influences of colored and turbid samples, but also can keep the inherent selectivity for the solid-contact Ca²⁺-ISE, since the signal detection based on the PB-based electrochromic device and the ion recognition based on the solid-contact Ca²⁺-ISE are separately placed. This work provides a simple, fast, and visual readout strategy for solid-contact ISEs, and expands the sensing concepts for reading out the potentiometric responses.

提出了基于电致变色普鲁士蓝（PB）器件的比色和库仑双模传感策略，用于读取固体接触离子选择电极（ISE）的电位响应。机理是PB基电致变色器件的漂白态和着色态之间的转变是通过使用固体接触Ca ²⁺ -ISE来调节的，在恒定电位的控制下改变离子活性，以及​​瞬态还获得了与PB的氧化还原反应有关的电流。结果表明，浓度范围为1.0 × 10 ^-6 -1.0 × 10 ^-2 Ca ²⁺可以通过肉眼观察颜色变化或通过智能手机分析红-绿-蓝（RGB）值以及应用控制下的PB基电致变色器件的相应积分电荷来定性和半定量检测潜在的。这些建议的读出策略不仅不受有色和混浊样品的影响，而且可以保持对固体接触 Ca ²⁺ -ISE 的固有选择性，因为基于 PB 基电致变色装置和离子的信号检测基于固体接触Ca ²⁺ -ISE的识别被分开放置。这项工作为固体接触 ISE 提供了一种简单、快速和可视的读出策略，并扩展了读出电位响应的传感概念。