Performance enhancement of perovskite solar cells with Mg-doped TiO2 compact film as the hole-blocking layer

Abstract

In this letter, we report perovskite solar cells with thin dense Mg-doped TiO 2 as hole-blocking layers (HBLs), which outperform cells using TiO 2 HBLs in several ways: higher open-circuit voltage (V oc ) (1.08 V), power conversion efficiency (12.28%), short-circuit current, and fill factor. These properties improvements are attributed to the better properties of Mg-modulated TiO 2 as compared to TiO 2 such as better optical transmission properties, upshifted conduction band minimum (CBM) and downshifted valence band maximum (VBM), better hole-blocking effect, and higher electron life time. The higher-lying CBM due to the modulation with wider band gap MgO and the formation of magnesium oxide and magnesium hydroxides together resulted in an increment of V oc . In addition, the Mg-modulated TiO 2 with lower VBM played a better role in the holeblocking. The HBL with modulated band position provided better electron transport and hole blocking effects within the device. V C 2015 AIP Publishing LLC.

Improved Solar-Driven Photocatalytic Performance of Highly Crystalline Hydrogenated TiO2 Nanofibers with Core-Shell Structure

“…Work function (WF) is derived from subtracting the cut-off binding energy with the photon energy (21.22 eV). The WF of pristine TiO 2 NFs and H:TiO 2 NFs are 5.33 and 5.91 eV, respectively64. The expanded valence spectra of pristine TiO 2 NFs and H:TiO 2 NFs are shown in Fig.…”

The Electronic Structures and Optical Properties of Alkaline-Earth Metals Doped Anatase TiO2: A Comparative Study of Screened Hybrid Functional and Generalized Gradient Approximation

“…Meanwhile, the increasing of open-circuit voltage ( V oc ) was reported for DSSC fabricated by using Mg-doped anatase-TiO 2 electrode [19]. The outperformance of perovskite solar cells with thin dense Mg-doped TiO 2 as hole-blocking layers was also reported [20,21]. Therefore, alkaline-earth metallic (AEM) dopant can improve the performance of TiO 2 in photocatalysis and solar cells.…”

Electron transport layer driven to improve the open-circuit voltage of CH3NH3PbI3 planar perovskite solar cells

“…Therefore, the ETL in N-I-P type planar structure is essential for the crystallization and morphology of perovskite films [15,16] and used to extract electrons [17][18][19]. Until now, TiO 2 is the most widely used ETL in perovskite solar cells [20][21][22]; however, ZnO has a higher carrier mobility, conductivity and a similar energy band profile with TiO 2 , ensuring a faster electron transport. Moreover, good electrical conductivity [23] can guarantee even in the deposition process at room temperature.…”