Enhanced charge extraction in carbon-based all-inorganic CsPbBr3 perovskite solar cells by dual-function interface engineering

97.3% Pb-Reduced CsPb1–xGexBr3 Perovskite with Enhanced Phase Stability and Photovoltaic Performance through Surface Cu Doping

“…The calculated band gap, effective electron mass, and effective hole masses by the GGA functional are 1.77 eV, 0.19 m 0 , and 0.29 m 0 , respectively, which are consistent with previous reports. ,, Consequently, CsPbBr 3 shows a small exciton binding energy of ∼55 meV, suggesting the easy separation for the photogenerated electron–hole pairs . The band gap, VBM, and CBM levels calculated by the HSE functional are 2.21, −5.85, and −3.64 eV, respectively, which are close to the experimental measures. − …”

Grain Enlargement and Defect Passivation with Melamine Additives for High Efficiency and Stable CsPbBr3 Perovskite Solar Cells

“…Ta ble 1s ummarizes the photovoltaic parameters of V OC ,s hortcircuit current density (J SC ), fill factor (FF), and PCE for various devices.T he photovoltaic performance of the devices based on M-CsPbBr 3 is evidently improved, ac hampion 1%M-CsPbBr 3 -based device displays the optimal performance with a PCE of 9.65 %, J SC of 7.42 mA cm À2 , V OC of 1.584 V, andF Fo f 82.11%,y ieldingamarked improvement in comparison with the pristine CsPbBr 3 PSC (PCE:6 .07 %, J SC :5 .87 mA cm À2 , V OC : 1.401 V, and FF:7 3.80 %) and other reportedC sPbBr 3 solar cells. [34,[39][40][41][42][43][44][45] The dramaticallyl ongerp hotovoltage decay time of the 1%M-CsPbBr 3 -based device compared to that of the control PSC in the dark demonstrates the lower charger ecombination rate of the former,w hich is responsible for the substantially increased V OC as well as J SC outputa nd therefore the PCE (FigureS7). The photovoltaic data of the devices show a downward trend after the addition of melamine exceeds 1%, which is ascribed to the decrease in grain size and the impure phase appearance of the 2% and 4%M-CsPbBr 3 as shown in Figure 2f and Figure 3a.T ov erify the repeatability of the device performance enhancement, the statistical distributions of photovoltaicp arameters (PCE, J SC , V OC ,a nd FF) for 30 random devicesw ere recorded with and without melamine ( Figure S8).…”

“…Table summarizes the photovoltaic parameters of V OC , short‐circuit current density ( J SC ), fill factor (FF), and PCE for various devices. The photovoltaic performance of the devices based on M‐CsPbBr 3 is evidently improved, a champion 1 % M‐CsPbBr 3 ‐based device displays the optimal performance with a PCE of 9.65 %, J SC of 7.42 mA cm −2 , V OC of 1.584 V, and FF of 82.11 %, yielding a marked improvement in comparison with the pristine CsPbBr 3 PSC (PCE: 6.07 %, J SC : 5.87 mA cm −2 , V OC : 1.401 V, and FF: 73.80 %) and other reported CsPbBr 3 solar cells . The dramatically longer photovoltage decay time of the 1 % M‐CsPbBr 3 ‐based device compared to that of the control PSC in the dark demonstrates the lower charge recombination rate of the former, which is responsible for the substantially increased V OC as well as J SC output and therefore the PCE (Figure S7).…”

“…The PL properties are characterized to better understand the effect of the perovskite film with melamine addition on the internal charge transportation of the devices. The steady‐state PL spectra of FTO/c‐TiO 2 / m ‐TiO 2 /various CsPbBr 3 samples are shown in Figure a; the 1 % M‐CsPbBr 3 film deposited on FTO/c‐TiO 2 / m ‐TiO 2 exhibits the weakest intensity of the PL emission peak, demonstrating a rapid photogenerated carrier extraction and separation inside the perovskite film, which is mainly due to the well‐matched energy level. Also, the blueshift phenomenon of the PL emission peak is consistent with the result shown in Figure c. In addition, the TRPL spectra of the corresponding PSCs were further recorded to study the charge extraction dynamics and carrier lifetime (Figure b).…”

Efficient and Stable All‐Inorganic Perovskite Solar Cells

“…As a result, the all‐inorganic PSCs with KOH modification delivered a high PCE of 11.78% for an active area of 0.09 cm 2 and 9.34% for an active area of 1.0 cm 2 , which dramatically outperformed 9.36% of the control device. Tang and coworkers [ 164 ] synthesized a series of CsPbI 3− x Br x NCs to modify CsPbBr 3 /carbon interface. It was found that the PCE was improved for all CsPbI 3− x Br x NCs regardless of the ratio of I with Br, but the best performance was obtained for CsPbI 3 NCs without Br.…”