Fabrication of high-performance non-enzymatic sensor by direct electrodeposition of nanomaterials on porous screen-printed electrodes

• A high-performance sensor was fabricated by screen printing and electrodeposition. • The screen-printed electrode was rendered porous by blending CaCO 3 in carbon paste. • Electrodeposition achieved consistent distributions of graphene and Ni nanoparticles. • The chemical state of Ni nanoparticles were unified to Ni(OH) 2 by electro-oxidation. • The sensor attained a highly linear detection with a 83% lower standard error. Screen-printed sensors can be easily fabricated and have advantages of cost-effectiveness, low instrument demand, and decentralized fabrication. However, they often suffered from low reproducibility and conductivity, restraining them from practical applications. This study demonstrated a high-performance sensor with large surface area, high conductivity, wide detection range, and consistent catalytic kinetics using screen printing and electrodeposition. The large surface area was achieved by blending sacrificer into carbon paste to fabricate porous electrodes. Two steps of electrodeposition decorated the porous electrode surface with graphene and nickel nanoparticles to enhance conductivity and enable catalytic reactions of lactate. Electrodeposition achieved consistent size and spatial distributions of graphene and Ni nanoparticles, enabling high conductivity and reactivity. The deposited nickel nanoparticles were a mixture of Ni 2+ and Ni 3+ derivatives, resulting in a high variation in response currents. By oxidizing the Ni-derivatives NPs to a uniform state of nickel hydroxide, the sensor attained a highly linear detection with an 83% lower standard error. Additionally, the improved sensor had an impressive linear detection range from 0.5 to 60 mM. The fabrication was easy to follow and had a minimum demand for the instrument, making it particularly valuable for practical applications in regions with limited resources.