论文标题
pH敏感的超薄氧化物液金属系统：了解基本感应机制
pH-Sensitive Ultra-thin Oxide-Liquid Metal System: Understanding the Fundamental Sensing Mechanism
论文作者
论文摘要
研究了液体金属（Eutectic Gainsn）的pH响应，以吊坠滴的形式进行了研究，并获得了4至10的pH范围内92.96 mV的敏感性。 Unlike the fundamental limit of pH sensitivity of 59.1 mV in an electrolyte-site binding surface, the super-Nernstian pH sensitivity originated from a spontaneous electrochemical reaction associated with an enhanced ionic exchange at the ultra-thin (1-3 nm) Ga2O3-electrolyte interface which is purely driven by thermodynamics, rendering to the lowest system energy possible involving gallate and双 - 气离子。通过引入离子交换因子X来解释超核PH敏感性，并发现pH敏感性与Pourbaix pH ph-potital配方之间的直接联系来得出统一的Nernst方程。发现Nernstian灵敏度为59.1 MV仅是用于对称离子交换（X = 1）反应的，而不对称离子交换可能导致敏感性远远超出了Nernst敏感性。我们的发现具有很大的科学意义，可以重新定义固态电化学传感器中离子传感机制的常规概念，并推动基于2D的基于氧化物的电化学传感器的未来发展。
The pH response of liquid metal (eutectic GaInSn) in the form of a pendant drop is investigated and the sensitivity of 92.96 mV in the pH range from 4 to 10 is obtained. Unlike the fundamental limit of pH sensitivity of 59.1 mV in an electrolyte-site binding surface, the super-Nernstian pH sensitivity originated from a spontaneous electrochemical reaction associated with an enhanced ionic exchange at the ultra-thin (1-3 nm) Ga2O3-electrolyte interface which is purely driven by thermodynamics, rendering to the lowest system energy possible involving gallate and bi-gallate ions. A unified Nernst equation is derived by introducing an ion-exchange factor x to explain superNernstian pH sensitivity and found a direct link between pH sensitivity and Pourbaix pH-Potential formulations. It is found that Nernstian sensitivity of 59.1 mV occurs only for symmetric ion exchange (x=1) reaction, whereas asymmetric ion exchanges could result in sensitivity far beyond the Nernst sensitivity. Our findings have great scientific significance, which could redefine the conventional concept of the ion sensing mechanism in a solid-state electrochemical sensor and push forward the future development of the 2D oxide-based electrochemical sensor.
