A polymer solution containing 0.5 wt.% polydiallyl dimethyl ammonium chloride was used to modify graphitic carbon nitride by the sol-carbonization method (PDDA (0.5) @ g-C3N4). Titanium dioxide nanoparticles were synthesized by microwave irradiation followed by hydrothermal treatment to obtain titanium nanowires (TiNWs). The TiO2NWs/ (PDDA (0.5) @g-C3N4) nanocomposite was prepared with different wt. % of TiO2NWs to (PDDA (0.5) @g-C3N4), 50:50, and 30:70 by the wet impregnation method. The prepared nanocomposites were applied in twin applications: photo-catalysis and quantum dot solar cells. Basic blue (Bb) and Methyl Orange (MO) were used as pollutants, and the degradation efficiencies were 96, 94, 90.8, 63.7, and 30.7% for TiO2NWs/ (PDDA (0.5) @g-C3N4) (50:50), TiO2NWs/ (PDDA (0.5) @g-C3N4) (30:70), TiO2NWs, g-C3N4, and (PDDA (0.5) @ g-C3N4), respectively, compared with the control experiment (without catalyst) at 14.8%. A perceived improvement in photovoltaic performance of TiO2NWs/ (PDDA (0.5) @g-C3N4) (50:50) was observed. A conversion efficiency of 2.8% with a VoC of 504 mV, JSC of 9.92 mA cm -2 , and a fill factor (FF) of 0.58 was achieved using 7 layers of CdS QD by the SILAR method.

In this paper the Modified Down Flow Hanging Sponge (DHS) reactor will be a good water treatment technology in the near future. It was used for excellent removal of notorious heavy metals, organic pollutants and harmful microbes. The reactor has advantages like low cost, ease of use and satisfaction level. In order to achieve these objectives, treatment scheme has been investigated. It consists of mixing a chelator with wastewater in different concentrations followed by a Down flow hanging sponge (DHS) reactor. The residual values of heavy metals are (Mn)amount decreases from 1 ppm to zero ppm (100%) after 60 min.,(Fe)decreases from 0.997 ppm to zero ppm (100%) after 60 min. (Cd) decreases from 0.901 ppm to zero ppm (100%) after 60 min. (Cu)decreases from 1.1 ppm to zero ppm (100%) after 60 min. (Pb)decreases from 1.004 ppm to zero ppm (100%) after 60 min. (Ni)decreases from 0.922 ppm to 0 ppm (100%) after 60 min. The results show that removals of fecal coliforms were achieved. From the results of DHS effluent, fecal coliforms decreased from 5.2x10 6 to 200 and the overall removal efficiency of fecal coliforms is (99.99%) at 37C o .