Abstract: Disclosed herein are a novel crown ether with bulky and rigid groups and a method for preparing the same. Also provided are a lithium adsorbent comprising the novel crown ether immobilized onto a nanofiber, and a method for preparing the same. The lithium-selective crown ether is synthesized through intermolecular cyclization between a bulky epoxide and a rigid aromatic compound such as 1,2-dihydroxybenzene, and can effectively recover lithium ions. For use as a lithium adsorbent, the novel crown ether with both bulky and rigid subunits is immobilized onto a polymer nanofiber. The crown ether-immobilized polymer nanofibers may be formed into a recyclable membrane.