context: Inspired by the superior ORR and OER electrocatalytic activities as well as excellent faradaic redox performance of the DBHF fibers, hybrid Zn batteries were fabricated. In the HZB, the DBHF fibers act as the cathode, Zn nanosheets on carbon cloth serve as the anode and a mixed solution of 6 M KOH and 0.2 M Zn(Ac)2 serves as the electrolyte. The charge/discharge performance of the hybrid Zn battery is investigated. As displayed in Fig. 6a, a smooth and flat voltage plateau at ∼1.21 V is detected in the initial discharging process, which indicates the ORR process of a typical Zn–air battery. In the subsequent charging process, the two voltage plateaus at ∼1.85 V and ∼2.05 V correspond to the M–O oxidation and the OER process, respectively. During the second discharge process, two voltage plateaus appear at ∼1.74 V and ∼1.21 V corresponding to the reduction reaction of M–O–OH and the ORR process, respectively. The charge/discharge results are in good agreement with the CV curves (Fig. S7†). Both results demonstrate that the fabricated hybrid battery is able to reversibly store and deliver charges via double sets of electrochemical reactions. They are the ORR/OER reactions in the Zn–air battery and the M–O/M–O–OH redox reaction in the Zn-ion battery assembled in one battery. Such a combination of complementary strength leads to a powerful hybrid Zn battery based on the Zn–air and Zn-ion systems.
answer: DBHF fibers