Fig 1

(a) Schematic of fabrication process of SnO2/AH ETL-based PSCs. Top-view SEM images of (b) pristine SnO2"

Fig 2

3D AFM morphology images of (a) SnO2 ETL and (b) SnO2/AH ETL. (c) Surface height distributions and (d) surface roughness of SnO2 and SnO2/AH ETLs. (e) Schematic for the better lattice match after AH modification."

Fig 3

(a) XRD patterns of SnO2/AH ETL deposited on FTO substrates. (b) XPS spectra of SnO2 and SnO2/AH ETLs. High-resolution XPS spectra of (c) Cl 2p, (d) N 1s for SnO2 and SnO2/AH ETLs. (e) Transmission spectra of FTO, SnO2 and SnO2/AH."

Fig 4

(a, b) Top-view SEM images and (c) XRD patterns of P-PSK and AH-PSK. (d) FWHM of the diffraction peak corresponding to (110) lattice plane. The contact angles of water droplets on (e) P-PSK and (f) AH-PSK."

Fig 5

(a, b) AFM images and (c, d) KPFM images of P-PSK and AH-PSK. (e) Surface roughness of P-PSK and AH-PSK. (f) Surface potential distributions of P-PSK and AH-PSK."

Fig 6

(a, b) Pseudocolor plots and (c, d) transient TA spectra of FTO/SnO2/PSK and FTO/SnO2/AH/PSK excited by 325 nm pump pulse. (e) Normalized GSB2 recovery kinetics of SnO2/PSK and SnO2/AH/PSK probed at 740 nm. (f) Schematic of the charge generation and extraction at FTO/SnO2/PSK and FTO/SnO2/AH/PSK interfaces."

Table 1

Fitting parameters for the normalized GSB2 recovery kinetics of SnO2/PSK and SnO2/AH/PSK probed at 740 nm."

Fig 7

(a) J–V curves and (b) IPCE spectra and integrated current densities of P-PSC and AH-PSC. (c) I–V curves with the structure of FTO/SnO2/Au and FTO/SnO2/AH/Au. (d) Steady-state photocurrent and PCE measured at the maximum power point. (e) EIS and (f) J–V curves of P-PSC and AH-PSC measured in darkness."

Table 2

Detailed photovoltaic parameters for P-PSC and AH-PSC."