Green synthesized nitrogen-doped nickel hexacyanoferrate incorporated in guar gum-xanthan gel for efficient sunlight-driven degradation of water pollutants

Herein, nitrogen-doped nickel hexacyanoferrate (N@NiHCF) nanoparticles were prepared via co-precipitation and incorporated in guar gum (GG)-Xanthan gum (Xa) based-polymeric-matrix (GGXa@N@NiHCF) for efficient removal of rose bengal (RB) dye and nonyl phenol (NP) pollutants under sunlight. PXRD, FESEM, XPS, and FTIR analysis verified successful integration of N@NiHCF nanoparticles into GGXa matrix. Scherrer and Williamson-Hall equations estimated average-crystallite sizes of GGXa@N@NiHCF nanoparticles to be 16.34 nm. TGA analysis and zeta potential values (-17.7 mV for N@NiHCF and -22.9 mV for GGXa@N@NiHCF nanocomposite) confirmed structural stability. N@NiHCF has band gap of 2.3 eV, demonstrating enhanced photocatalytic efficiency due to improved light absorption and charge separation. Photocatalytic experiments demonstrated high degradation rates of RB (91 %) in 150 min and NP (95 %) in 300 min under optimized conditions highlighting composite's effectiveness. Kinetics of photodegradation process were studied using Hinshelwood formula, yielding rate constant of 0.93 min^-1 (t_1/2 = 0.74 h) for RB and 0.60 min^-1 (t_1/2 = 1.14 h) for NP with GGXa@N@NiHCF. LC-MS analysis identified degradation pathways, indicating transformation of pollutants into safer byproducts. Recyclability study showed sustained performance over multiple cycles, emphasizing nanocomposite's durability. This study provides insights into applying GGXa@N@NiHCF, highlighting its promise as a sustainable approach for mitigating water pollution.