本研究透過簡單的電化學沉積以及退火技術，成功的在碳布上製備出ORR與OER催化活性均表現優異的雙功能空氣陰極。實驗中，我們進行多部分的研究，從篩選材料、改變退火溫度、摻雜第二種金屬、確認摻雜後退火溫度，最後到比較不同La濃度對性質影響，並選出適當的摻雜濃度進而組裝成電池。並透過SEM、EDS、XRD、Raman、XPS、TEM來分析表面特徵，電化學以及電池性質測試則藉由雙頻恆電位/電流/交流阻抗儀進行量測。
根據SEM結果得知，電沉積Co源並經由退火後會使表面結構改變，產生奈米片狀結構，XRD以及Raman分析則確認此結構為尖晶石Co3O4，而藉由適當的鑭摻雜則可取代部分Co3+，導致有更高的比表面積，進而有更多的催化活性位點，增進電子效益提升導電性，並藉XPS分析探討鑭摻雜濃度對於取代Co3+對性質之影響。
電化學量測結果顯示，在0.1 M KOH氧氣環境下，La0.025-Co/CC-350薄膜有著良好的ORR與OER性能，經LSV氧氣還原反應量測，半波電位達到0.85 V，Tafel斜率值為21.5 mV/dec；而析氧反應在10 mA cm-2電流密度時，過電壓為0.33 V，Tafel斜率值為41.2 mV/dec；CV量測電雙層電容值為99.2 mF/cm2。因此，我們將性質優異的La0.025-Co/CC-350作為空氣陰極，對電極為鋅，電解液為6 M KOH與0.2 M醋酸鋅，經過全電池量測後，開路電壓為1.42 V，得到比電容為789 mAh/gzn、能量密度為903 Wh/kg，並經充電及放電各10分鐘，循環300次後(100小時)，電壓間隙僅增加0.02 V；而鋅空氣電池理想觸媒Pt/C+RuO2比電容為736 mAh/gzn、能量密度為908 Wh/kg，長時間充放電則無法達到300次循環，再次證明本研究之雙功能觸媒的優異性。

A bifunctional Zn-air battery air cathode with excellent catalytic activity for both ORR and OER was successfully fabricated on carbon cloth through simple electrochemical deposition and annealing techniques. The experiment can be divided into multiple sections, from screening materials, changing the annealing temperature, doping the second metal, confirming the annealing temperature after doping, comparing the effect of different La concentrations on the properties, and finally selecting the appropriate doping concentration to assemble into a zinc air battery. The surface features were analyzed by SEM, EDS, XRD, Raman, XPS, and TEM. The electrochemical and battery properties were measured by electrochemical testing.
According to the SEM results, the electrodeposition of the Co source and annealing change the surface structure, resulting in a nano-flake structure. XRD and Raman analysis confirm that this structure is Co3O4 spinel. By partially replaced Co3+ by lanthanum at appropriate doping amount, the La-doped Co3O4 led to a higher specific surface area for more catalytically active sites, which is expected to enhance electrode surface reaction and improves electrical conductivity. XPS analysis was used to explore the effect of lanthanum doping concentration on the electrode properties of Co3O4.
The electrochemical measurement results showed that the La0.025-Co/CC-350 film had good ORR and OER performance in the 0.1 M KOH electrolyte purged with flowing oxygen to keep oxygen environment. The half-wave potential reached 0.85 V and the Tafel slope value was 21.5 mV/dec. When the oxygen evolution reaction was conducted at a current density of 10 mA cm-2, the overpotential of 0.33 V and the Tafel slope value of 41.2 mV/dec were achieved. The double-layer capacitance value measured by CV was 99.2 mF/cm2. Therefore, we selected La0.025-Co/CC-350 with excellent electrode properties as the cathode and zinc foil as the anode to assemble of zinc-air battery in an electrolyte with 6 M KOH and 0.2 M zinc acetate. The full battery showed the open circuit voltage of 1.42 V, the specific capacity of 789 mAh/gzn, and the energy density of 903Wh/kg. For a cyclic stability test at charging and discharging for 10 minutes each, the zinc-air battery had energy gap of 0.88 V after 300 cycles (100 hours) with only a 0.02 V increase. The Pt/C+RuO2 is an ideal model catalyst for the air cathode of zinc-air battery with the specific capacity of 736 mAh/gzn and the energy density of 908 Wh/kg, but it cannot sustain the 300-cycle charge and discharge stability test. At last, this work has achieved a bifunctional La-doped Co3O4 air cathode for zinc-air battery, which is superior to the model Pt/C+RuO2 air cathode.

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