The mercury ion (Hg²⁺) is regarded as one of the toxic cations that is extremely harmful and dangerous to human health and the environment. With this growing awareness, it is imperative that facile and rapid sensing systems developed for the detection of Hg²⁺. Due to excellent sensitivity and selectivity, graphene quantum dots (GQDs), a zero-dimensional carbon nanomaterial, are attracting the attention of researchers as promising candidates as fluorescent probes for Hg²⁺ detection. This study aimed at conducting an in-depth review of recent advances into GQD-based materials as fluorescent probes in Hg²⁺ sensing. This systematic review was carried out by covering three main databases, namely, Scopus and Science Direct as the dominant databases, followed by Google Scholar as the supporting database. GQD-based materials encompassing bare GQDs, N-GQDs, B, N-GQDs, N, S-GQDs, N, K-GQDs, RhB-GQDs, Cys-GQDs, PEHA-GQD-DPA, Gly-GQDs, Mn(II)-N-GQDs, NH₂–Ru@ SiO₂-NGQDs and FA-GQDs were discussed thoroughly with regard to their synthesis strategies, along with their potential application in the detection of Hg²⁺. The doping of heteroatoms is envisaged to enhance the quantum yield and selectivity of bare GQDs. This review might unlock a wide range of opportunities for the application of various GQD-based materials as an adaptable, feasible and scalable approach to the detection of Hg²⁺.

汞离子（Hg ²⁺）被认为是对人类健康和环境极其有害和危险的有毒阳离子之一。随着这种意识的增强，开发用于检测 Hg ^{2+ 的}简便快速的传感系统势在必行。由于出色的灵敏度和选择性，石墨烯量子点 (GQD)，一种零维碳纳米材料，作为检测Hg ^{2+ 的}荧光探针的有前途的候选材料，正吸引着研究人员的注意。本研究旨在深入回顾基于 GQD 的材料作为 Hg ^{2+ 中的}荧光探针的最新进展感应。本次系统评价覆盖了三个主要数据库，即Scopus和Science Direct作为主导数据库，其次是Google Scholar作为支持数据库。基于 GQD 的材料包括裸 GQD、N-GQD、B、N-GQD、N、S-GQD、N、K-GQD、RhB-GQD、Cys-GQD、PEHA-GQD-DPA、Gly-GQD、Mn( II)-N-GQDs、NH ₂ –Ru@SiO ₂ -NGQDs 和 FA-GQDs 就它们的合成策略以及它们在检测 Hg ²⁺中的潜在应用进行了深入讨论. 杂原子的掺杂旨在提高裸 GQD 的量子产率和选择性。这项审查可能会为应用各种基于 GQD 的材料作为一种适应性强、可行且可扩展的方法来检测 Hg ²⁺提供广泛的机会。