| The alkaline Zn/MnO2 battery are widely used in civil and industrial fields due to its large capacity, high specific energy, wide working temperature range, good leak-proof performance, long storage life and high integrated cost-effective. Manganese dioxide is often used as a cathode material for an alkaline Zn/MnO2 battery due to its good electrochemical properties, favorable cost structure and low toxicity. However, at high discharge rates, the utilization rate of the manganese dioxide cathode is low. For example, only 30-40% of the active material in an alkaline Zn/MnO2 battery is utilized in a high power electronic device. Therefore, how to improve the utilization of manganese dioxide is one of the key issues to make the traditional alkaline Zn/MnO2 batteries more effective at high discharge rates.In this paper, we have done some research for these problems. The contents and contributions are as following:(1) Two types of high-power mesoporous manganese dioxide battery materials were successfully prepared by using SBA-15 and KIT-6 as the hard templates, respectively, and manganese nitrate solution as the manganese source. The results showed that the MnO2 prepared using SBA-15 as the template is in the same perfect hexagonally mesostructured arrays as the channels of the SBA-15 mother mold and has a surface area of 112 m2·g-1; the MnO2 prepared using KIT-6 as the template is characterized by Ia3d cubic structure and has a surface area of 83 m2·g-1. From cyclic voltammograms two anodic peaks are observed at potentials of-480 mV and 220 mV, in addition, the area of the oxidation peak is larger than that of the reduction peak, which suggests that the reversibility of the two types of mesoporous MnO2 is better. Compared to the commercial electrolytic manganese dioxide (EMD), the discharge capacity of SBA-15-MnO2 increased by 74.98%,119.74% and 146.19% at constant currents of 50,250 and 500 mA·g-1, respectively, while the discharge capacity of KIT-6-MnO2 increased by 63.58%,95.14% and 100.23%.(2) We synthesized two types of non-metallic element doped mesoporous manganese dioxide battery materials by in situ doping non-metallic elements sulfur or selenium. The electrochemical performance test showed that the best doping element is selenium and the best doping amount is 5%. Compared to pre-doped, the discharge capacity of SBA-15-MnO2 reaches 506.25,430.25 and 376.2 mA·h·g-1, respectively, increased by 17.65%,24.98% and 28.94% at constant currents of 50,250 and 500 mA·g-1; while the discharge capacity of KIT-6-MnO2 reaches 516.25,465.97 and 378.2 mA·h·g-1, respectively, increased by 28.33%,52.41% and 59.38%.(3) In this paper, we also synthesized two types of metallic element doped mesoporous manganese dioxide battery materials by in-situ doping metal elements nickel, lead, cerium and magnesium. The electrochemical performance test showed that the best doping element is magnesium and the best doping amount is 5%. Compared to pre-doped, the discharge capacity of SBA-15-MnO2 reaches 510.26,454.86 and 401.2 mA·h·g-1, respectively, increased by 18.58%, 32.13% and 37.51% at constant currents of 50,250 and 500 mA·g-1; while the discharge capacity of KIT-6-MnO2 reaches 560.6,466.66 and 410.2 mA·h·g-1, respectively, increased by 39.36%, 52.64% and 72.86%.In this paper, two types of doped mesoporous manganese dioxide battery materials were prepared by in-situ doping. Mesoporous manganese dioxide have no significant impact on crystal form, morphology and structure, when the doping amount of less than 10%, regardless of doping non-metallic elements selenium, or a doped metal element magnesium. However, doped mesoporous manganese dioxide exhibited more excellent electrochemical performance. This provides a new approach for improving the high-power discharge performance of alkaline Zn/MnO2 battery cathode materials.
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