The real-time detection and monitoring of chloride ion concentrations play important roles in broad industrial applications, including wearable health care device, environmental pollutant control and infrastructure corrosion monitoring. The development of all-solid-state micro-fabricated electrochemical sensors has enabled the miniaturisation of these testing devices. This study reviewed the micro-fabricated electrochemical chloride sensors developed since 1970s, together with a brief summary regarding the progression of miniaturised electrochemical sensors in the past half century. Three major types of electrochemical chloride sensors with specific ion-selectivity have been discussed, the potentiometric sensors (including both ion-selective electrodes and chemical FETs), the chronopotentiometric sensors and the voltammetric sensors. In addition, colorimetric sensors, an emerging low-cost, portable, fast diagnose sensor technique has been included in this review. Four critical sensor performances have been reviewed and compared systematically, the sensibility (chloride concentration range), selectivity, lifetime and applicable pH ranges. The future perspectives for engineering applications proposed in this review will benefit the further development of integrated multi-functional sensors, as well as new instrumental testing methods.

中文翻译：

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微型电化学氯离子传感器：从现在到将来。

氯离子浓度的实时检测和监控在广泛的工业应用中起着重要作用，包括可穿戴医疗设备，环境污染物控制和基础设施腐蚀监控。全固态微制造电化学传感器的发展使这些测试设备得以小型化。这项研究回顾了自1970年代以来开发的微型电化学氯化物传感器，并简要概述了过去半个世纪中微型电化学传感器的发展。讨论了具有特定离子选择性的三种主要类型的电化学氯化物传感器：电位传感器（包括离子选择电极和化学FET），计时电位传感器和伏安传感器。此外，比色传感器是一种新兴的低成本，便携式，快速诊断传感器技术，已包含在本文中。传感器的四个关键性能已得到系统地审查和比较，灵敏度（氯化物浓度范围），选择性，寿命和适用的pH范围。本文中提出的工程应用的未来前景将有利于集成多功能传感器的进一步发展以及新的仪器测试方法。