Among the AKARI all-sky survey data, the $9{mu}m$ diffuse map is crucial to study the polycyclic aromatic hydrocarbon (PAH) emission features on large spatial scales, while the $18{mu}m$ map is useful to trace hot dust emission. To utilize these advantages, we have improved the AKARI mid-infrared (MIR) all-sky survey diffuse maps. For example, we have established special methods to remove the effects of the ionizing radiation in the South Atlantic Anomaly (SAA) and of the scattered light from the moon. Using improved diffuse map data, we study the properties of PAHs and dust in the Galactic center region associated with high-energy phenomena.