A series of vanadium-substituted Cs salt of heteropoly compounds (HPC) from different vanadium-containing precursors were synthesized to investigate the preferable vanadyl species for oxidation of isobutane to methacrylic acid (MAA) under oxygen-poor conditions. The effects of various precursors on the structure were explored by XRD, FT-IR, Raman, UV–vis diffuse reflectance, XPS, H₂-TPR, NH₃-TPD and IR spectra of pyridine adsorption, and their structure-performance relationship was further studied. It was firstly found that the vanadium-containing precursors played a crucial role in the structure (location of vanadyl species), surface acidity and redox properties (ratio of surface V⁴⁺/V⁵⁺ and Mo⁵⁺/Mo⁶⁺ redox couples) for series of as-prepared HPCs catalysts. The catalyst derived from vanadyl sulfate led to vanadyl species into the secondary structure of Keggin-type HPC, which exhibited suitable surface V⁴⁺/V⁵⁺ and Mo⁵⁺/Mo⁶⁺ ratio and higher surface acidity, thereby improving the catalytic activity and selectivity to MAA for selective oxidation of isobutane under oxygen-poor conditions. These understandings would be beneficial for further study of HPCs and developing of highly efficient catalysts for isobutane oxidation.

合成了一系列来自不同含钒前体的杂多钒化合物的钒取代Cs盐，以研究在贫氧条件下将异丁烷氧化为甲基丙烯酸（MAA）的优选钒基物质。通过XRD，FT-IR，拉曼，紫外可见漫反射，XPS，H ₂ -TPR，NH ₃ -TPD和吡啶吸附的IR光谱研究了各种前体对结构的影响，它们的结构-性能关系为进一步研究。首先发现含钒的前体在结构（钒基物种的位置），表面酸度和氧化还原特性（表面V ⁴⁺ / V ⁵⁺和Mo ⁵⁺ / Mo之比）中起着至关重要的作用。⁶⁺氧化还原对），用于一系列已制备的HPC催化剂。硫酸氧钒制得的催化剂使钒基物种进入Keggin型HPC的二级结构，表现出合适的表面V ⁴⁺ / V ⁵⁺和Mo ⁵⁺ / Mo ⁶⁺比，且表面酸度较高，从而提高了催化活性。贫氧条件下对异丁烷选择性氧化的MAA的选择性和选择性。这些理解将有助于进一步研究HPC和开发用于异丁烷氧化的高效催化剂。