Interfacial engineering by using self-assembled monolayer in mesoporous perovskite solar cell

Abstract

A self-assembled monolayer of 4-aminobenzoic acid (PABA) modified TiO2 layer improved the interfacial compatibility and the quality of the above-deposited perovskite, leading to the power conversion efficiency of the device to be enhanced to 10.58%.

Molecular Interlayers in Hybrid Perovskite Solar Cells

“…[29,41,46,81] The carboxyl group binds strongly to the oxide making them robust interlayers and the wide range of dipole moments accessible through functional group modification can provide favorable conditions for charge extraction at a variety of interfaces. With an appropriate dipole moment, a benzoic acid derivative can be used to improve the V oc , either as a cathode interlayer or an anode interlayer.…”

“…In perovskite solar cells, links between perovskite layer and contact layer are improved when the the interlayer moleules have terminal amino groups. [29,69] For instance, a group of mole ucles with generic structure HOOCRNH 3 I has been used to modify TiO 2 surfaces. [68] These molecules bind the TiO 2 surface through the carboxyl groups and participate in the crystallization process of the perovskite via the NH 3 terminus.…”

“…Those most frequently used include perylene and its derivatives, [28,40,42,70,71] benzoic acid and its derivatives, [29,72] aminofunctionalized small molecules, [32,73] silanes, [31] dyes, [74] and fullerene derivatives. [75] As listed in Table 2, different molecules are employed depending on the aim of the research.…”

“…It is worth noting that the orientation in which PDIs pack or stack plays an important role in determining the electronic [42] Reduce R s 14.0% versus 11.3% (average) ITO/PEDOT:PSS/PTB7:PCBM/ PDINO/metal [40] Reduce work function and R s 7.7% versus 4.4% FTO/c-TiO 2 /m-TiO 2 /benzoic acid derivatives/FA x MA 1−x PbI 3−y Br y / spiro-OMeTAD/Au [69] Enhance charge extraction speed 18.4% versus 17.5 FTO/c-TiO 2 /m-TiO 2 /benzoic acid derivatives/CH 3 NH 3 PbBI 3 / spiro-OMeTAD/Au [29] Reduce surface defects 10.5% versus 7.5% ITO/PEDOT:PSS/P3HT:PCBM/ZnO/ benzoic acid derivatives/metal [41] Reduce work function 3.2% versus 0.7% ITO/benzoic acid derivatives/ PTB7:PCBM/Al [30] Increase work function/morphological control 8.2 versus 5.1%…”

N-type metal-oxide electron transport layer for mesoscopic perovskite solar cells

“…The average PCE of HTL-free, fully printable MPSCs based on a carbon counter electrode is improved from 9.6% to 11.7%, with a highest efficiency of 12.7%. Li et al [73] modified the TiO2 ETL with alkylphosphonic acid ω-ammonium chlorides. The phosphonic acid ammonium additive acts as a crosslinker between TiO2 and perovskite through strong hydrogen bonding of the -PO(OH)2 and -NH3 + terminal groups to the perovskite surface.…”