Fabrication of Cs0.33WO3-g-C3N4-rGO nanocomposite for near-infrared shielding and photocatalysis applications

• The Cs 0.33 WO 3 -g-C 3 N 4 -rGO nanocomposite owns the multifunctionality of NIR shielding and photocatalytic application. • Double-sided coating has better NIR shielding performance than coexistence coating. • The photocatalytic performance is strongly affected by the g-C 3 N 4 and rGO concentration. • The highest NIR shielding, RhB degradation, and NOx degradation respectively were obtained in C5 sample. Cesium tungsten bronze (Cs 0.33 WO 3 ) is one of the near-infrared (NIR) shielding materials that has unique properties, such as excellent visible transmittance, high transparency, and near-infrared absorption. Nowadays, the utilization of cesium tungsten bronze-based nanocomposites as smart coatings for windows with multifunctional of NIR shielding and self-cleaning ability is attracted to be explored. The addition of g-C 3 N 4 and rGO to the Cs 0.33 WO 3 is necessary to enhance the photocatalytic activity and self-cleaning ability of nanocomposites while maintaining excellent visible transmittance and NIR shielding properties. In this work, the Cs 0.33 WO 3 were fabricated using the solvothermal method, followed by physical mixing to obtain Cs 0.33 WO 3 -g-C 3 N 4 -rGO nanocomposites. The concentrations of g-C 3 N 4 and rGO were varied to study the effect on the NIR shielding and photocatalytic properties. All the coexistence and double-sided composite films showed visible light transmittance above 70 %, and the thermal insulation increased by the combination with g-C 3 N 4 and rGO. Moreover, the increment of g-C 3 N 4 content also enhanced the Rhodamine B photodegradation ability of nanocomposites compared to pure Cs 0.33 WO 3 . The C5 sample (Cs 0.33 WO 3 54.6 %, g-C 3 N 4 43.6 %, rGO 1.8 %) achieved the highest photodegradation of Rhodamine B at 96.03 % and NO x at 33 %, while it is only 13.07 % and 12 % for pure Cs 0.33 WO 3 , respectively. Thus, the as-prepared Cs 0.33 WO 3 -g-C 3 N 4 -rGO nanocomposites would become an alternative material in the field of energy-saving and environmental purification.