Pulsed laser deposition of manganese oxide thin films for supercapacitor applications
Pulsed laser deposition of manganese oxide thin films for supercapacitor applications
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DOI：
10.1016/j.jpowsour.2011.06.045
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发表时间：
2011-10
影响因子：
9.2
通讯作者：
Dongfang Yang
中科院分区：
文献类型：
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作者：
Dongfang Yang
采用脉冲激光沉积（PLD）技术，在不同衬底温度和氧气压力下，在硅片和不锈钢衬底上生长了锰氧化物薄膜。通过适当选择PLD工艺中的温度和氧气压力等工艺参数，成功制备了纯晶相Mn 2 O3、Mn 3 O 4和非晶相MnOx。在0.1M Na_2SO_4水溶液中，用电化学循环伏安法研究了不同扫描速率下锰氧化物的赝电容行为。结果表明，晶态Mn 2 O3相的比电流和比电容最高，而晶态Mn 3 O 4膜的比电流和比电容最低。非晶态MnOx薄膜的比电流和比电容值低于Mn_2O_3但高于Mn_3O_4。在1 mVs-1扫描速率下，厚度为120 nm的Mn 2 O3薄膜的比电容达到210 Fg-1，具有良好的稳定性和循环耐久性。这项工作表明，PLD是一个非常有前途的技术，筛选高性能的活性材料的超级电容器应用，由于其良好的灵活性和能力，易于控制的化学组成，微观结构和相的材料。
Thin films of manganese oxides have been grown by the pulsed laser deposition (PLD) process on silicon wafer and stainless steel substrates at different substrate temperatures and oxygen gas pressures. By proper selection of processing parameters such as temperature and oxygen pressure during the PLD process, pure crystalline phases of Mn2O3, Mn3O4as well as amorphous phase of MnOxwere successfully fabricated as identified by X-ray diffraction. The pseudo-capacitance behaviours of these different phases of manganese oxides have also been evaluated by the electrochemical cyclic voltammetry measured in 0.1M Na2SO4aqueous electrolyte at different scan rates. Their specific current and capacitance determined by electrochemical measurements were compared and the results show that crystalline Mn2O3phase has the highest specific current and capacitance, while the values for crystalline Mn3O4films are the lowest. The specific current and capacitance values of the amorphous MnOxfilms are lower than Mn2O3but higher than Mn3O4. The specific capacitance of Mn2O3films of 120nm thick reaches 210Fg−1at 1mVs−1scan rate with excellent stability and cyclic durability. This work has demonstrated that PLD is a very promising technique for screening high performance active materials for supercapacitor applications due to its excellent flexibility and capability of easily controlling chemical composition, microstructures and phases of materials.