Effect of hydrolysis catalyst and photo-catalysis performance exploration of rutile nanocrystal derived from screen printing waste: A waste to wealth approach

High-crystalline nanoparticles (NPs) were explored for the first time as a waste-to-wealth approach, utilizing rutile NPs from screen-printing waste as a predominant reactant catalyst for the hydrolysis, denoted as X at pH 7.0 and Y at pH 9.0. The NPs were investigated using state-of-the-art instrumentation XRD, DLS, zeta sizer, UV-Vis-NIR, TGA-DSC, SEM, TEM, SAED and EDS techniques to assess their crystal identities. Crystalline rutile explored average crystallite sizes of 96.32 and 82.78 nm for X, Y respectively, depicted nanocrystals. The computed lattice parameters of X, a=b= 4.59579 Å, c= 2.96027 Å and Y, a=b= 4.59526 Å c= 2.95979 Å express identical symmetry and weight fraction in the whole powder pattern fitting (WPPF) method in 100 % rutile phase. The Zeta wall potential showed higher electrostatic stability of Y than X. The transmission electron microscopy (TEM) morphography explored nano-sized distribution in the inner core particle and the selected area electron diffraction (SAED) pattern showed Y to be more crystalline than X. The estimated band gap energy was 2.31 eV for X and 2.73 eV for Y, demonstrating quantum confinement effects at higher pH which explores photoactivity. Scanning electron microscopy (SEM) explored the surface morphology in which the particle uniformly grows on surface Y than X. The energy dispersive spectroscopy (EDS) pattern in TEM confirmed atomic mass percentages of 61.41 % Ti and 38.59 % O of X; on the other hand, 62.60 Ti % and 37.40 O % were shown in Y. Thermo-gravimetric and differential scanning calorimetry (TGA-DSC) analysis revealed high thermal stability up to 800 °C. The wettability of Y is greater than X revealed by the drop shape analyzer. The photocatalytic degradation of Crystal Violet (CV) dye under halogen radiation showed degradation efficiencies of 69.0 % to 70.89 % respectively, indicating that X followed zero-order kinetics whereas Y followed second-order kinetics, suggesting the dependence on reactant concentration at higher pH. The catalyst showed outstanding performance in several recycling tests. These findings demonstrate the potential of TiO 2 nanocrystals derived from industrial waste for environmental remediation. 1. X computed lattice parameters a = b = 4.59579 Å, c = 2.96027 Å with α = β = γ = 90°. 2. Excellent thermal stability up to 800 °C. 3. Y computed lattice parameters a = b = 4.59526 Å c = 2.95979 Å with α = β = γ = 90°. 4. Tuned band gaps were 2.31 eV for X and 2.73 eV for Y due to quantum confinement. 5. Photo-catalysis performance: 70.89 % of Y following second-order kinetics. • TiO 2 NPs were developed from screen-printing waste pH 7.0 (X) and 9.0 (Y) media. • SEM explored the particle uniformly grows on surface Y than X. • Tuned band gaps were 2.31 eV for X and 2.73 eV for Y to quantum confinement. • Excellent thermal stability up to 800 °C for X and Y. • Photo-catalysis performance 69 % to 70.89 % of X and Y.