High-quality molybdenum disulfide nanosheets with 3D structure for electrochemical sensing

MoS2 ultrathin nanosheets are successfully synthesized via a facile strategy, one-step pyrolysis of ammonium molybdate, thiourea and layered g-C3N4 template. Possessing hierarchical porous structure and large pore volume as well as good conductivity, MoS2 ultrathin nanosheets demonstrates significantly improved electrocatalytic activity toward oxidation of AA, DA, and UA. [Display omitted] •MoS2 ultrathin nanosheets are achieved via a facile strategy, one-step pyrolysis of ammonium molybdate, thiourea and layered g-C3N4 template.•The sacrificial template (g-C3N4) plays a significant role in this synthetic process, which brings ultrathin structure and three-dimensional porous network for MoS2 materials.•The MoS2 ultrathin nanosheets sample displays significantly improved electrocatalytic performance toward oxidation of AA, DA, and UA, manifesting enlarged peak separation and increased peak current.•Meantime, simultaneous determination of these biomolecules is achieved in a wide concentration rang with high sensitivity, selectivity, stability and good reproducibility on modified electrode of the MoS2 nanosheets. An electrochemical sensor has been developed for simultaneous detection of dopamine (DA), uric acid (UA) and ascorbic acid (AA) based on pure MoS2 nanosheets modified electrode. The MoS2 nanosheets are achieved via a facile strategy, one-step pyrolysis of ammonium molybdate, thiourea and layered g-C3N4 template. Possessing hierarchical porous structure and large pore volume as well as good conductivity, MoS2 nanosheets demonstrates significantly improved electrocatalytic activity toward oxidation of AA, DA, and UA. In the coexisting system, the peak separation of AA–DA, DA–UA and AA–UA is 208.3mV, 128.0mV and 336.3mV, respectively, which is much larger than for other MoS2-based catalyst. On the basis of large potential separation and high current response, selective and sensitive simultaneous determination of AA, DA, and UA was successfully accomplished by DPV, displaying a linear response from 5 to 1200μM, from 1 to 900μM, and from 1 to 60μM with a detection limit (S/N=3) of 0.82, 0.15, and 0.06μM. This work highlights the importance of Mo-edge sites of MoS2 and hierarchical porous structure for efficient catalysis.