Sustainable wastewater sludge@bimetallic cadmium-MOFs and nano-copper oxide as a promising shielding composite for gamma rays: Experimental and simulation investigations

Conventional waste-water sludge disposal methods often result in a substantial amount of solid waste and environmental pollution when dealing with construction waste. Thus, the principal goal of this investigation is to create sustainable sludge-based materials containing various weight fractions of bimetallic metal-organic framework (Cd-MOFs), and nano-copper oxide (N-CuO) for potential shielding applications such as gamma and neutron radiations. Bimetallic Cd-MOFs and N-CuO were combined with sludge powder by liquid-phase synthesis approach for the formation of SCdMCu-X nanocomposites where, X=0, 1, 3, and 5. FT-IR, DSC, XRF, TEM, and Raman analysis were used to characterize the raw sludge, Cd-MOFs, N-CuO, and the produced nanocomposites. The radiation shielding properties were empirically determined using an HPGe detector at 0.661-1.332 MeV and theoretically determined using Monte Carlo code and PhYX software in the photon energy range 0.030-15 MeV. The prepared SCdMCu-X samples with significant Cd-MOFs doping exhibited an exceptional linear attenuation and effective atomic number. N-CuO and Cd-MOFs were found to enhance the gamma and neutron radiation shielding. The produced SCdMCu-5 sample with the highest content of Cd-MOFs revealed the most significant improvement in gamma and neutron radiation shielding effectiveness compared to the other SCdMCu-X samples. Mixing the waste-water sludge with the nano-materials (N-CuO, Cd-MOFs), gives a good indication that will open the door for converting the useless waste-water sludge to processing materials that could be used in radiation shielding in the nuclear installations.