Functionalized Cellulose‐Co(II)‐Bis‐Terpyridine Hybrid Material as Colorimetric Sensor for Micromolar Aqueous Cyanide

Abstract

AbstractA novel surface modification approach is taken to cyanide‐sensing by using functionalized cellulose surface that is chemically modified by immobilizing cobalt(II)‐bis‐terpyridine complex on it. The cobalt(II)‐bis‐tpy complex can exhibit selective “naked eye” colorimetric detection of micromolar level cyanide in aqueous solution, where the visible red‐orange color of cobalt(II)‐bis‐tpy complex solution (aqueous) disappears in the presence of cyanide ions. In order to make the sensor more proficient and easy to use, these cobalt(II)‐bis‐tpy molecules are chemically grafted on the surface of microcrystalline cellulose and cellulose paper, which turns the color of functionalized cellulose orange‐red. Both of these colored cellulose powder and paper exhibit color loss in 10−6m aqueous solution of potassium cyanide. This functionalized hybrid inorganic–organic paper offers an easy “dip and detect” cyanide sensing.