Generating Huge Magnetocurrent by Using Spin-Dependent Dehydrogenation Based on Electrochemical System

Abstract

Systems featuring large magnetocurrent (MC) at room temperature are attractive owing to their potential for application in magnetic field sensing. Usually, the magnetic materials are exploited to achieve large MC effect. Here, we report a huge MC of up to 150% in a nonmagnetic system based on the electrochemical oxidation of hydrazine at room temperature. The huge MC is ascribed to the spin-dependent N–H bond cleavage and reformation through dehydrogenation during the oxidation of hydrazine. Specifically, the N–H bond cleavage generates singlet radical pairs. An external magnetic field can accelerate the spin evolution from singlet to triplet in spin-correlated radical pairs by perturbing spin precessions. Increasing the amount of triplet radical pairs can largely reduce the N–H bond recovery and significantly enhance the oxidation current of hydrazine. As a consequence, the spin-dependent bond formation through dehydrogenation can provide a new approach to generate huge MC in electrochemical cells.