State Key Laboratory of Clean and Efficient Coal Utilization, Taiyuan University of Technology
Key Laboratory of Coal Science and Technology, Taiyuan University of Technology, Ministry of Education
State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences
School of Chemistry and Environmental Science, Shangrao Normal University

甲酸 (FA) 因其H含量较高 (4.4%)、易产H2、可经小平台化合物合成等优势受到广泛关注，而γ-Mo2N/C对FA沿H2和CO2路径分解具有非常高的选择性，产生CO极少，显示出较高的应用价值。基于此，本研究采用对苯二胺和钼酸铵水溶液经前驱体制备γ-Mo2N/C催化剂，并对其FA分解性能进行了原位评价，采用热重分析 (TG)、X射线衍射 (XRD)、傅里叶变换红外光谱 (FT-IR)、扫描电镜 (SEM)、透射电镜 (TEM) 等表征手段对催化剂的结构和表面官能团进行了分析，利用DFT对FA在γ-Mo2N (200) 晶面的吸附构型进行了计算，在此基础上，对催化剂性能及FA在其表面的分解机理进行了研究。结果表明，γ-Mo2N/C在较低温度下即可表现出极高的催化活性，提高γ-Mo2N在C载体上的分散性能有效改善FA转化率。对苯二胺与钼酸铵的物质的量比为4∶1时，催化性能最佳，在160 ℃、100 h的FA分解实验中，催化剂性能稳定、H2选择性高(N2 40 mL/min, CO<5.0×10−5)。而DFT计算表明，FA中O−H键的H原子与γ-Mo2N/C (200) 晶面上N原子结合的可能性更大，而C=O键的O原子更有可能与γ-Mo2N/C (200) 晶面上Mo原子结合。上述结果有助于明确FA在γ-Mo2N/C作用下的分解机理，也显示出非贵金属催化剂γ-Mo2N/C在FA分解制H2方面潜在的应用前景。

Formic acid (FA) has received much attention due to its high hydrogen content (4.4%), easy H2 production and synthesis from small platform compounds. γ-Mo2N/C is very selective for the decomposition of FA along the H2 and CO2 pathways, generating very little CO and showing high application value. In this study, γ-Mo2N/C catalysts were prepared using aqueous p-phenylenediamine and ammonium molybdate solutions as precursors, and their FA decomposition performance was evaluated in-situ. The adsorption conformation of FA on the crystalline surface of γ-Mo2N (200) was calculated by DFT, and on this basis, the catalyst performance and the decomposition mechanism of FA on its surface were investigated. The results showed that γ-Mo2N/C exhibited very high catalytic activity at low temperatures and that improving the dispersion of γ-Mo2N on the C carrier was effective in improving the FA conversion. The best catalytic performance was achieved at a molar ratio of 4∶1 between p-phenylenediamine and ammonium molybdate, and the catalyst showed stable performance and high H2 selectivity (N2 40 mL/min, CO<5.0×10−5) in the FA decomposition experiments at 160 ℃ and 100 h. DFT calculations showed that the H atom of the O−H bond in FA was more likely to bind to the N atom on the crystalline surface of γ-Mo2N/C (200), while the O atom of the C=O bond are more likely to bind to Mo atoms on the γ-Mo2N/C (200) crystal plane. The above results help to clarify the mechanism of FA decomposition under the action of γ-Mo2N/C and show the potential application of the non-precious metal catalyst γ-Mo2N/C in the decomposition of FA for H2 production.

路军, 王美君, 王志青, 董立波, 余钟亮, 常丽萍. γ-Mo2N/C催化剂的合成及其甲酸脱氢性能研究[J]. 燃料化学学报（中英文）, 2024, 52(1): 76-86.

LU Jun, WANG Meijun, WANG Zhiqing, DONG Libo, YU Zhongliang, CHANG Liping. Synthesis of γ-Mo2N/C catalysts and its performance on formic acid dehydrogenation[J]. Journal of Fuel Chemistry and Technology, 2024, 52(1): 76-86.