募 is built from the 莫 (not / sunset) and 力 components.
It belongs to a phonetic family with 模, 暮, 墓, and 慕 — they share the 莫 component and the reading ボ.
A common word using 募 is 募集 (ぼしゅう), meaning “recruitment”.
Don't confuse it with 模, 暮, 墓, and 慕.
