Tungsten Powder, Positive Electrode Body For Capacitors, And Electrolytic Capacitor

The present invention provides a tungsten powder for electrolytic capacitors, which has elemental molybdenum only in a surface region (a first surface region) of each particle such that the content of the elemental molybdenum is 0.05-8% by mass, and which has good leakage current (LC) performance. It is preferable that: the tungsten powder has a volume average primary particle diameter of 0.1-1 mumm; the elemental molybdenum is localized in a region from the particle surface to the position 20 nm deep toward the inside of the particle in each particle; at least one selected from among tungsten silicide, tungsten in which nitrogen is solid-solved, tungsten carbide and tungsten boride is present in a surface region (a second surface region) of each particle; and the content of elemental phosphorus is 1-500 ppm by mass. 本发明提供种漏电流(LC)性能良好的电解电容器用的钨粉，该钨粉仅在粒子的表面区域(第1表面区域)具有钼元素，且钼元素的含量为0.05～8质量％。优选钨粉的体积平均次粒径为0.1～1μm，钼元素局部存在于从其粒子表面向粒子内部深入20nm的位置为止的区域，并且在粒子表面区域(第2表面区域)具有硅化钨、氮固溶化了的钨、碳化钨、硼化钨的至少1种，磷元素的含量为1～500质量ppm。