Efficient Carbon-Based CsPbBr3 Inorganic Perovskite Solar Cells by Using Cu-Phthalocyanine as Hole Transport Material

Abstract

Metal halide perovskite solar cells (PSCs) have attracted extensive research interest for next-generation solution-processed photovoltaic devices because of their high solar-to-electric power conversion efficiency (PCE) and low fabrication cost. Although the world’s best PSC successfully achieves a considerable PCE of over 20% within a very limited timeframe after intensive efforts, the stability, high cost, and up-scaling of PSCs still remain issues. Recently, inorganic perovskite material, CsPbBr3, is emerging as a promising photo-sensitizer with excellent durability and thermal stability, but the efficiency is still embarrassing. In this work, we intend to address these issues by exploiting CsPbBr3 as light absorber, accompanied by using Cu-phthalocyanine (CuPc) as hole transport material (HTM) and carbon as counter electrode. The optimal device acquires a decent PCE of 6.21%, over 60% higher than those of the HTM-free devices. The systematic characterization and analysis reveal a more effective charge transfer process and a suppressed charge recombination in PSCs after introducing CuPc as hole transfer layer. More importantly, our devices exhibit an outstanding durability and a promising thermal stability, making it rather meaningful in future fabrication and application of PSCs.Electronic supplementary materialThe online version of this article (10.1007/s40820-018-0187-3) contains supplementary material, which is available to authorized users.

Promoting the Hole Extraction with Co3O4 Nanomaterials for Efficient Carbon‐Based CsPbI2Br Perovskite Solar Cells

“…The reduced τ 2 mainly comes from the increased charge extraction from CsPbI 2 Br film to carbon electrode, which is beneficial to suppress the charge recombination at the CsPbI 2 Br/C interface . This indicates that the Co 3 O 4 HTM can significantly reduce charge recombination, resulting in the enhanced photovoltaic performance in Co 3 O 4 ‐PSC . This is in agreement with the J – V and EQE measurements in Figure .…”

“…Compared to the Co 3 O 4 ‐PSC, the reference PSC shows the worse performance with a J sc of 12.78 mA cm −2 , a V oc of 1.097 V, a FF of 66.11% and a PCE of 9.27% in the RS direction. The lower PCE might be due to the sluggish charge extraction at the perovskite/carbon interface to limit the photovoltaic performance . When the Co 3 O 4 HTM is inserted into the CsPbI 2 Br/C interface, the PCE is significantly enhanced and Co 3 O 4 ‐PSC achieves a champion PCE of 11.21% in the RS direction.…”

Review on Recent Progress of All‐Inorganic Metal Halide Perovskites and Solar Cells

“…Liu et al used Cu‐Phthalocyanine as a hole transport material combined with a printable carbon electrode, which is one of the choices for a suitable low‐cost scalable contact material. With CsPbBr 3 as absorber a PCE of 6.2% has been achieved on an area of 1 cm 2 and 4.7% on 2.25 cm 2 .…”

Recent Progress of All‐Bromide Inorganic Perovskite Solar Cells

“…Copper phthalocyanine (CuPc), as a p‐type semiconductor material, also can be used as HTL. The high mobility of 10 −3 –10 −2 cm 2 V −1 S −1 , superior stability (degradation above 500 °C in air), and long diffusion length (8–68 nm) ensure effective hole extraction in the devices . CsPbBr 3 ‐based PSCs with a CuPc HTL deposited on top of CsPbBr 3 layer by thermal evaporation and then carbon paste applied as electrode were devised.…”