多孔隙雙金屬銅/鈷有機金屬骨架(Cu/Co-MOF)薄膜主要由銅摻雜的Co-MOF (Co2(6-mercaptonicotinate)2, CUK-2)與少量的鈷摻雜Cu-MOF ([Cu2(6-mercaptonicotinic acid)(6-mercaptonicotinate)]·NH4)組成，藉由下列六步驟的長晶機制鍵結在導電基材上：(i)錨定一層6-mercaptonicotinate (6-MNA)修飾層至基材；(ii) 硫醇基去質子化；(iii) 形成金屬−硫鍵；(iv) 6,6'-dithiodinicotinic acid (H2dtdn)釋出去質子化6-MNA；(v) 形成金屬-硫、金屬-氮或金屬-氧鍵；(vi) MOF晶體結構的展延。透過此方法可在沒有其他干擾物（包含客體分子、黏合劑或MOF衍生物）的情況下，量測MOF材料自身的本質電催化特性。使用碳布作為導電基材時，碳布中的碳纖維可作為一維導電核心，包覆其上的雙金屬Cu/Co-MOF薄膜可作為電催化外殼，可建立核/殼結構的階層式電荷傳輸路徑。雙金屬Cu/Co-MOF薄膜同時具備了由Co-MOF所提供的高孔隙度，也擁有Cu-MOF所提供的高導電度，此協同效應使雙金屬Cu/Co-MOF擁有較佳的本質電催化特性。在三維結構的Co-MOF中含有大量的一維彈簧狀(−Co−S−)n鏈作為活性位點，而二維Cu-MOF中含有許多二維蜂巢狀(−Cu−S−)n平面作為快速電子傳導路徑。因此，使用最佳雙金屬Cu/Co-MOF(9.96%)作為對電極之染敏電池相較於純Co-MOF(9.93%)、純Cu-MOF(9.36%)、白金(9.25%)之電池有更突出表現。在三種氧化−還原對（I−/I3−、Co(II/III)和Cu(I/II)錯合物）中可觀察到雙金屬Cu/Co-MOF出色的電催化劑活性，揭示了非導電、導電或雙金屬MOF應用於各種電化學系統的無限潛力。

A mesoporous film of bimetallic Cu/Co-MOF, mainly composed of Cu-doped Co2(6-mercaptonicotinate)2 (CUK-2, denoted as Co-MOF hereafter) with minor particles of Co-doped [Cu2(6-mercaptonicotinic acid)(6-mercaptonicotinate)]·NH4 (Cu-MOF), was covalently bonded to a conducting substrate via a six-step crystal-growth mechanism: (i) anchoring a modification layer of 6-mercaptonicotinate (6-MNA) on a substrate; (ii) deprotonation of thiol; (iii) formation of metal−S bonds; (iv) releasing of deprotonated 6-MNA from H2dtdn; (v) coordination of metal−S, metal−N or metal−O bonds; (vi) extension of MOF building block. The evaluation of the intrinsic electro-catalytic ability of solely MOF particles can be thereby afforded without other interferences, including guest molecules, binders, or MOFderivatives. When the coating was on a CC substrate, a hierarchical charge transfer pathway was established by the core/shell structure of carbon fiber/MOF; where each carbon fiber in CC acted as a 1D conducting core, covered by a bimetallic Cu/Co-MOF film as an electro-catalytic shell. In a bimetallic Cu/Co-MOF film, an improved intrinsic electro-catalytic ability was obtained due to the synergetic effect of large active sites and facile charge-transfer; the former was supplied by numerous springcoil-like 1D (−Co−S−)n chains in the mesoporous 3D Cu-doped Co-MOF particle, the latter was provided by many 2D (−Cu−S−)n honeycomb-like plains in highly conductive 2D Co-doped Cu-MOF. Accordingly, the cell coupled with an optimal bimetallic Cu/Co-MOF (9.96%) as the counter electrode outperformed the cells coupled with pristine Co-MOF (9.93%), pristine Cu-MOF (9.36%), and Pt (9.25%) electrodes. The outstanding electro-catalyst activity of bimetallic Cu/Co-MOF was observed in three redox mediators (I−/I3−, cobalt(II/III), and copper(I/II) complex), revealing the infinite potential of non-conductive, conductive, or bimetallic MOF for various electrochemical systems.

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