Abstract Herein alkali metal (Na/K) doped graphitic carbon nitride (g-C3N4) was fabricated using a facile one-pot route. The as synthesized three materials; bulk g-C3N4 (CN-B), K doped g-C3N4 (K-CN-300) and Na doped g-C3N4 (Na-CN-x) were well characterized using various characterization techniques. CN-B, K-CN-300 and Na-CN-x modified glassy carbon electrode were used as electrochemical nitrite sensor. Among them Na-CN-300 showcased impressive electrochemical current response under optimized condition. The Na doping into CN-B enhanced the electrochemical response of CN-B towards nitrite detection. The fabricated sensor exhibits excellent electrochemical performance and gave linear response for nitrite concentration range of 10 μM to 2 mM with LOD of 1.9 μM. Moreover the sensor displayed impressive selectivity, sensitivity and reproducibility, which are qualities of a good sensor material. In an attempt to fabricate disposable electrochemical sensor, Na-CN-300 was applied on a screen printed electrode and its stability was tested for 30 days. The proposed sensor was deployed for detection of nitrite in real samples (water and food), representing its possibilities for real-time analysis.

中文翻译：

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碱金属 (Na/K) 掺杂的石墨氮化碳 (g-C3N4)，用于水和食品样品中亚硝酸盐的高选择性和灵敏电化学检测

摘要 本文采用简便的一锅法制备了碱金属 (Na/K) 掺杂的石墨氮化碳 (g-C3N4)。合成了三种材料；使用各种表征技术对块体 g-C3N4 (CN-B)、K 掺杂 g-C3N4 (K-CN-300) 和 Na 掺杂 g-C3N4 (Na-CN-x) 进行了很好的表征。CN-B、K-CN-300和Na-CN-x修饰的玻碳电极用作电化学亚硝酸盐传感器。其中 Na-CN-300 在优化条件下展示了令人印象深刻的电化学电流响应。掺杂到 CN-B 中的 Na 增强了 CN-B 对亚硝酸盐检测的电化学响应。制造的传感器表现出优异的电化学性能，并在 10 μM 至 2 mM 的亚硝酸盐浓度范围内提供线性响应，LOD 为 1.9 μM。此外，该传感器显示出令人印象深刻的选择性、灵敏度和再现性，这是良好传感器材料的品质。在尝试制造一次性电化学传感器时，将 Na-CN-300 应用于丝网印刷电极并测试其稳定性 30 天。所提出的传感器用于检测实际样品（水和食物）中的亚硝酸盐，代表了其实时分析的可能性。