Nano-structured palladium impregnate graphitic carbon nitride composite for efficient hydrogen gas sensing

Nanoparticles of palladium (Pd) were incorporated into graphitic carbon nitride (g-C3N4) matrix with a view to improving hydrogen sensing efficiency of g-C3N4, by a fairly new chemical process that uses ammonium tetrachloropalladate as a Pd metal nanoparticle source along with an appropriate reducing agent. Researchers have explored g-C3N4 for various applications such as a catalyst for water splitting, photoluminescence, storage because of its relatively low cost, easy synthesis, and ready availability. For the synthesis of g-C3N4, urea was used as a precursor at 550 °C and at atmospheric pressure under a muffle furnace without add-on support. The final solution of the Pd/g-C3N4 nanocomposite was then centrifuged and dried for use as a hydrogen-sensing material. g-C3N4 and Pd/g-C3N4 were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), UV-VIS-NIR spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and energy dispersive X-ray spectroscopy (EDS). Pd-dispersed graphitic carbon nitride film was deposited on an inter digited carbon electrode by using a screen printing technique. From the qualitative analysis by I–V measurement, a significant change in the resistance was observed during the presence and absence of the hydrogen gas. The results show Pd/g-C3N4 nanocomposite as an efficient hydrogen sensing material.