Pt1/Ni6Co1 layered double hydroxides/N-doped graphene for electrochemical non-enzymatic glucose sensing by synergistic enhancement of single atoms and doping

The development of novel single-atom catalysts is important for highly efficient electrochemical catalysis and sensing. In this work, a novel Pt single atoms (SAs) supported on Ni6Co1 layered double hydroxides/nitrogen-doped graphene (Pt1/Ni6Co1LDHs/NG) was constructed for electrochemical enzyme-free catalysis and sensing towards glucose. The loading of Pt single atoms increases with doping of Co atoms that generate more anchoring sites for Pt SAs. The resulting Pt1/Ni6Co1LDHs/NG exhibits low oxidative potential of 0.440 V with high sensitivity of 273.78 µA·mM−1·cm−2 toward glucose, which are 85 mV lower and 15 times higher than those of Ni(OH)2, respectively. Pt1/Ni6Co1LDHs/NG also shows excellent selectivity and great stability during 5-week testing. Theoretical and experimental results show that the boosted performance of Pt1/Ni6Co1LDHs/NG originates from its stronger binding energy with glucose and the synergistic effect of Pt SAs, Co doping, and NG. This work provides a general strategy of designing highly active SACs for extending their application in electrochemical sensing.