Alkali metals co-doped graphitic carbon nitride(g-C_3 N_4)was prepared using melamine as precursor,KCl and NaCl as molten salts,and characterized by X-ray diffraction(XRD),N_2 adsorption,UV-vis spectroscopy,X-ray photoelectron spectroscopy(XPS),and Photoluminescence(PL).By controlling the weight ratio of eutectic salts to melamine,the VB and CB potentials of prepared g-C_3 N_4 could be tuned from +1.55 Vand-1.10 Vto+2.27 Vand-0.27 V,respectively.Besides,the ions embedding inhibited the crystal growth,enhanc...