Gold is one of the potential toxic heavy metals. In the present study, Au³⁺ was detected and removed by newly-designed fluorescent microspheres (MF-CDs), i.e. melamine formaldehyde microspheres incorporated with N and S co-doped carbon dots (N,S-CDs). N,S-CDs played the role as sensing unites and melamine formaldehyde microspheres (MF) as carriers. When MF-CDs were attempted as the fluorescence probe, enhanced fluorescence sensing performance towards Au³⁺ was achieved with wider linear range (0.05 μM - 2 μM) and lower limit of detection (31 nM) compared to the N,S-CDs probe. In addition, when MF-CDs were used as the adsorbent, the adsorption capacity towards Au³⁺ reached up to 1 mmol g^-1, about ten times more than that of MF. Moreover, the Au³⁺ adsorbed on the MF-CDs could be in-situ transferred to gold nanoparticle (AuNP), forming the immobilized nanocatalyst, i.e. MF-CDs-AuNP, which could further assist the reduction of 4-nitrophenol with acceptable reusability. This study paved an avenue to design the multifunctional materials for simultaneous detection, removal and recycling of environmental concerned pollutants.

金是潜在的有毒重金属之一。在本研究中，Au ³⁺被新设计的荧光微球（MF-CD）检测并除去，即掺有N和S共掺杂碳点（N，S-CD）的三聚氰胺甲醛微球。N，S-CD充当传感单元，三聚氰胺甲醛微球（MF）作为载体。当尝试将MF-CDs用作荧光探针时，与N，S-CDs探针相比，在更大的线性范围（0.05μM-2μM）和较低的检测限（31 nM）下，获得了对Au ³⁺增强的荧光传感性能。。此外，当使用MF-CDs作为吸附剂时，其对Au ³⁺的吸附容量达到1 mmol g ^-1大约是MF的十倍。此外，吸附在MF-CDs上的Au ³⁺可以原位转移到金纳米颗粒（AuNP）上，形成固定化的纳米催化剂，即MF-CDs-AuNP，它可以进一步协助4-硝基苯酚的还原，并具有可接受的可重复使用性。这项研究为设计多功能材料以同时检测，去除和回收环境相关污染物铺平了道路。