Structuring Au nanoparticles on two-dimensional MoS2 nanosheets for electrochemical glucose biosensors

Two-dimensional (2D) bioelectronics is an emerging field of research which fuses the advantages of 2D nanomaterials with those of nanobiotechnology. Due to the various physical and chemical properties present in layered counterparts of 2D materials, including high charge density, large surface area, remarkable electron mobility, ready electron transport, sizeable band gaps and ease of hybridisation, they are set to become a versatile tool to fabricate sensitive and selective novel biodevices, which might offer an unique advantages to tackle key energy, medical and environmental issues. Current 2D bioelectronics research is focused on the design of simple-to-use and cheaper biodevices, while improving their selectivity, sensitivity and stability. However, current designs generally suffer from a lack of efficiency, relatively low sensitivity, slow electron transfer kinetics, high background charging current and low current density arising from poor mass transport. Here, we report a nanoparticle-structured MoS2 nanosheet as an ideal semiconductor interface, which is able to form a homogenous layer on the electrode surface for the assembly of gold nanoparticles. This not only enhances electrocatalytic reactions, but also provides excellent electrochemical properties such as high faradic-to-capacitive current ratios, high current density and electron mobility, and faster mass transport, due to the dominance of radial diffusion. The MoS2/Au NPs/GOx bioelectrode exhibits a linear response to glucose from 0.25 to 13.2mM, with a detection limit of 0.042µM (S/N=3) and sensitivity of 13.80µA/µM/cm2. •Structuring of gold nanoparticles on two-dimensional molybdenum disulfide (MoS2) nanosheets in a one-step reaction.•MoS2 as a semiconductor, which is an ideal candidate to form homogenous layer on the electrode surface for the structuring of Au NPs.•The fabrication of an electrochemical biosensor based on MoS2 nanosheets is demonstrated.•Design interface could potentially provide significant improvements in biocatalysis and nanotechnology by exploiting this biocatalytic interface with a variety of redox enzymes.