在本研究中利用高分子聚乙烯吡咯烷酮(PVP)、氧化石墨烯(GO)、有機配位體5-氨基四唑以及硝酸鈷在一步簡易水熱法的條件下合成鈷金屬有機骨架/摻氮還原氧化石墨烯之氧氣還原/氧氣氧化雙功能之電觸媒。從穿透式及掃描式電子顯微鏡可看出成功將金屬有機骨架生成於氮摻雜還原氧化石墨烯上，其粒徑大小約20~30 nm；更進一步透過拉曼圖譜及X光電子繞射鑑定可以確認鈷金屬有機骨架/氮摻雜還原氧化石墨烯奈米材料結構。為了改善觸媒催化效果，將鈷金屬有機骨架/氮摻雜還原氧化石墨烯在混合氣(95%Ar+5%H2)下500℃鍛燒三個小時，透過氫氣處理有效提升摻氮還原氧化石墨烯的還原程度，同時將導電性不佳中孔洞金屬有機骨架分解成鈷金屬/氧化鈷/四氧化三鈷/摻氮還原氧化石墨烯的結構(CoNRGO)，其顆粒大小約50~60 nm。所得具最佳電催化特性之CoNRGO，其氧氣還原反應及氧氣產生反應之起始電位分別為 0.85 V與1.55 V (V vs. RHE)。其雙功能電催化指標 ΔE之最低值為0.83 V，且穩定性勝過商用觸媒。進一步將CoNRGO組裝成液態及全固態鋅空氣電池，顯示其具有良好的可充放電特性及高功率密度(液態鋅空氣電池為111 mW cm-2、全固態鋅空氣電池為79 mW cm-2 )與高能量密度(全固態鋅空氣電池為563 Wh kg-1)。在實際應用中，兩種型態電池皆能使LED燈發亮。據此，本研究提出一創新且簡易的方式製得以金屬有機骨架為犧牲模板之雙功能氧氣電催化觸媒，並成功將其實際應用於鋅空氣電池中。

In this study, at first, the Co-based MOFs embedded in nitrogen-doped reduced graphene oxide (MOFs/NRGO) was synthesized as an effective electrocatalyst for ORR/OER by a facile one-step hydrothermal reaction in a mixture of graphene oxide (GO) solution, polyvinylpyrrolidone, cobalt nitrate, and organic ligands 5-amino-1H-tetrazol. From TEM and SEM analyses, it was found that the MOFs nanoparticles with an average size of about 20-30 nm have been decorated successfully on the surface of NRGO nanosheets. Also, from the XRD and Raman analyses, the formation of MOFs/NRGO could be confirmed. Secondly, the MOFs/NRGO was further pyrolyzed in Ar/H2 (95/5) atmosphere. The result showed that hydrogen gas could enhance the reduction degree of NRGO and made the MOFs turn into Co/CoO/Co3O4/NRGO (CoNRGO) with an average size of about 50-60 nm at a relatively low temperature. Its onset-potentials for ORR and OER were 0.85 V and 1.55 V (V vs. RHE), respectively. Also, it showed the lowest ΔE of 0.83 V and better stability than commercial catalysts. Furthermore, CoNRGO was used to assemble the liquid-type and all-solid-state Zn-air batteries which could power a LED light and exhibited good rechargeability, high power densities and high energy density. Accordingly, this work provided a facile and effective strategy for the fabrication of MOF-derived bifunctional oxygen catalysts and the resulting CoNRGO could be successfully utilized in Zn-air batteries.

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