Fig. 2. (a) FE-SEM image of TPG-75. (b) HR-TEM image of TPG-75 showing lattice fringes and d-spacing; SAED pattern is shown as an inset. (c) UV-vis DRS pattern of TPG-75 (inset shows the corresponding Tauc plot). (d) Mott–Schottky measurement of TPG-75. (e) Photocurrent measurements of TPG-75, Tp-Pa, and gC₃N₄ under visible light irradiation on and off conditions with a time interval of 20 seconds. (f) EIS of TPG-75, Tp-Pa, and gC₃N₄.