乙腈(Acetonitrile, AcCN)是一廣泛被應用於各種領域(如: 製藥、液相層析、電解液等)高價值的化學品，而利用觸媒將甲烷(methane)轉化為乙腈之方法尚未被探討。本研究以不同固體氮源(melamine, melem, g-C3N4)合成氮化鎵(GaN)，探討因不同固體氮源及鎵的前驅物(氧化鎵、硝酸鎵)合成之 GaN 對甲烷轉乙腈反應性之影響。結果顯示，無論使用何種固體氮源，皆可以合成出活化甲烷的必要活性物質 GaN，但相較於使用 melamine、melem 作為固體氮源，以 g-C3N4 合成出之 GaN 觸媒擁有著極為良好的鎵分散性以及最多的 CN-活性物質，且擁有最佳的觸媒表現(乙腈之產率較高)。此外，當合成 GaN 時，提升 g-C3N4 的添加量(提高前驅物 N/Ga 重量比)，可以使 Ga 分散性愈好以及提高殘留於觸媒中的 CN-活性物質量，而反應性也隨之提升。經由測試商業用之 GaN 行甲烷轉化反應得知，雖然仍可以觀察到甲烷轉化成的 C2 產物，但乙腈的產量微乎其微，因此我們認為，欲將甲烷直接轉化成乙腈，除了活化甲烷所需要的 GaN 外，仍可能有其餘的活性點位。我們進行一系列的觸媒物化性鑑定，如 XRD、BET、XAS、XPS、FTIR、Air- IR、CH4-IR、RAMAN、TGA、EA、Air-TPSR，於本文中進行探討。

Acetonitrile (AcCN) is a valuable chemical with many applications such as pharmaceuticals, liquid chromatography, electrolyte, and platform chemical. The production of AcCN from methane with catalysis method has not be developed yet. This study investigated the mixtures of Ga (β-Ga2O3 or gallium nitrate hydrate) and N (melamine (C3N6), melem (C3N5), or g-C3N4) precursors in the modified solid-state pyrolysis and applied their derived GaN catalysts in the nonoxidative conversion of methane to acetonitrile (AcCN). Except the effect of different nitrogen sources and nitrogen precursor amount (N/Ga precursor weight ratio = 0.5, 1, 2) was discussed, we also found the indispensable active sites in as-synthesized GaN for producing AcCN. Commercial GaN showed almost no activity for producing AcCN, the main product with as-synthesized gallium nitrides. However, we still can observe C2 species, the main nonoxidative products, during the reaction for all of these catalysts. We suggested that the active phase for activating methane, which was GaN, was successfully synthesized. Moreover, there is another important active specie for generating AcCN. Possibly from the mobile N species on the surface.

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