Hybrid-power wireless electrochemical platform coupled to screen-printed electrode module for natural water monitoring

The aim of this paper is to present a practical hybrid-power method for wireless chemical sensor of radio-frequency identification. Radio-frequency carrier is divided into dual-direction signal chain and single-direction power chain where 3-W wireless power transfer with ∼71% efficiency is possible. This feature is further enhanced by introducing a power management unit (PMU) coupled to a super capacitor. The hybrid of wireless power transfer and self-powered PMU provides a high-power window and a low-EMI window as long as 120 s. They contribute to powerful operations and high-performance measurements. A wireless electrochemical platform and a screen-printed electrode module are prepared to validate the proposed method. The electrode module is modified with multiple materials for pH sensing and stripping determinations of Cd(II) and Pb(II). The proposed method is evaluated by different means as scanning electron microscope, electrical measurement, cyclic voltammetry and stripping technique. Furthermore, it is used for natural water monitoring, and shows good stabilities and satisfying analytical properties in a 7-day period.