Cooperation of Zr(iv)–N and Zr(iv)–O coordinate bonds of Zr(iv)–amide ensures the transparent and tough polyacrylamide hydrogels

Zr-PAAm hydrogels prepared through a one-pot thermo-polymerization reaction in the presence of various Zr( iv ) salts displayed high toughness, high optical transparency, and rich interference colors under stretching.