The detection of some environmental pollutants remains still a great challenge and the current methods suffer from low sensitivity, reproducibility and require sophisticated instruments. Here, a simple, sensitive and pH‐responsive electrochemical sensor for the detection of hydroquinone (HQ) was developed based on a pH‐responsive block copolymer polystyrene‐b‐poly(acrylic acid) (PS‐b‐PAA) and graphene oxide (GO) composite film (PG) modified glassy carbon electrode (GCE). The electrochemical behaviors of HQ at the modified GCE (PG/GCE) electrode were studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The peak current of the PG/GCE electrode toward HQ was significantly enhanced at pH 7.0 and greatly suppressed below pH 6.0, which are caused by swelling and shrinking of pH‐responsive block copolymer and the synergistic effect with GO. The PG/GCE exhibited a reversible “On/Off” switch for the HQ electrochemical behaviors between pH 4.0 and pH 7.0. When the pH of the medium is 7.0, the PG complex film on the PG/GCE is in the “On” state, the linear detection range of HQ is from 16 μM to 104 μM with a detection limit as low as 0.34 μM. Furthermore, the PG/GCE can also successfully detect the HQ concentration of the lake water sample with satisfactory recovery, indicating that the pH‐responsive block copolymer/GO‐functionalized sensor provided a powerful avenue for simple, sensitive and convenient detection of HQ, which can be translated into practical application.

中文翻译：

---

基于聚苯乙烯-b-聚（丙烯酸）和氧化石墨烯复合膜的可逆pH响应型对苯二酚电化学传感器

某些环境污染物的检测仍然是一个巨大的挑战，目前的方法灵敏度低，可重复性差并且需要复杂的仪器。这里，用于检测对苯二酚的简便，灵敏及pH响应电化学传感器（HQ）的开发是基于pH响应嵌段共聚物聚苯乙烯-聚对b -聚（丙烯酸）（PS- b-PAA）和氧化石墨烯（GO）复合膜（PG）修饰的玻碳电极（GCE）。通过循环伏安法（CV）和电化学阻抗谱（EIS）研究了HQ在修饰的GCE（PG / GCE）电极上的电化学行为。PG / GCE电极向HQ的峰值电流在pH 7.0时显着提高，并在pH 6.0以下大大抑制，这是由于pH响应嵌段共聚物的溶胀和收缩以及与GO的协同作用所致。PG / GCE在pH 4.0和pH 7.0之间针对HQ电化学行为表现出可逆的“开/关”开关。当介质的pH值为7.0时，PG / GCE上的PG复合膜处于“开启”状态，HQ的线性检测范围为16μM至104μM，检测极限低至0.34μM。此外，