fig8

Figure 8. UV-vis spectra (A) PL spectra, (B) transient photocurrent response, (C) and (D) EIS Nyquist plots of the as-prepared samples. CDs/HCPP: Carbon dots incorporated in hydrochar; PP: pomelo peel; CDs: carbon dots; UV-vis: ultraviolet-visible; PL: photoluminescence; EIS: electrical impedance spectroscopy.