Graphitic C6N6-supported Dual Cu/Zn Single-Atom Catalyst Mimicking Allosteric Regulation for Intelligent Switching Biosensing

Self-adaptability is highly envisioned for artificial devices such as robots with chemical noses. To this end, seeking catalysts with reversibly switchable functions is promising but generally hampered by mismatched initial valence state of transition metal active centers and electronic structures. Herein, we report a graphitic C6N6-supported dual Cu/Zn single-atom catalyst with a synergistic effect (Cu/Zn-C6N6). It could not only rely on the Cu(I)/Cu(II) redox reaction with promotion from Zn to exhibit a remarkable superoxide dismutase-like (SOD) performance, but also activate Cu(I)/Cu(0) redox reaction to highly switch a marginable peroxidase-like (POD) activity, in which the initial oxidation state was transformed by a photoreduction. The multiformity of the cycles between different valence states for the same catalytic active center makes the reaction activity capable of being reversible switch, the switch efficiency can reach more than 90%. As a proof-of-concept application, Cu/Zn-C6N6 was further confined to a microfluidic chip and applied to a single-interface biosensor with reversibly switched ability in detecting xanthine and glucose in vitro.