Efficient adsorption and photocatalytic degradation of methylene blue using HKUST-1: A novel approach for dye removal and wastewater treatment under sunlight

In this study, a three-dimensional HKUST-1 metal-organic framework (MOF) was synthesized via a solvothermal method under optimized conditions (110 °C for 4 h), achieving high crystallinity and a yield of 75 %. The material was characterized using XRD, FESEM, FTIR, TG, and BET analysis, revealing a surface area of 534.7 m²/g, and the dual performance of HKUST-1 as both an adsorbent and a photocatalyst was investigated using Methylene Blue (MB) as a model pollutant. The material demonstrated an adsorption efficiency of 95.04 ± 1.00 % and a sunlight-driven photodegradation efficiency of 86 %, with a photodegradation rate constant of 0.019 ± 0.360 min⁻¹ , the radical scavenging experiments confirmed that superoxide radicals (•O₂⁻) were the dominant active species. Furthermore, the material retained over 80 % of its removal efficiency after four reuse cycles. These findings demonstrate that HKUST-1 is a promising bifunctional material for sustainable wastewater dye treatment under natural sunlight.