Facilely Synthesized spiro[fluorene‐9,9′‐phenanthren‐10′‐one] in Donor–Acceptor–Donor Hole‐Transporting Materials for Perovskite Solar Cells

Abstract

We have demonstrated two novel donor-acceptor-donor (D-A-D) hole-transport material (HTM) with spiro[fluorene-9,9'-phenanthren-10'-one] as the core structure, which can be synthesized through a low-cost process in high yield. Compared to the incorporation of the conventional HTM of commonly used 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), the synthesis process is greatly simplified for the presented D-A-D materials, including a minimum number of purification processes. This results in an increased production yield (>55 %) and suppressed production cost (<30 $ g ), in addition to high power conversion efficiency (PCE) in perovskite solar cells (PSCs). The PCE of a PSC using our D-A-D HTM reaches 16.06 %, similar to that of Spiro-OMeTAD (16.08 %), which is attributed to comparable hole mobility and charge-transfer efficiency. D-A-D HTMs also provide better moisture resistivity to prolong the lifetime of PSCs under ambient conditions relative to their Spiro-OMeTAD counterparts. The proposed new type of D-A-D HTM has shown promising performance as an alternative HTM for PSCs and can be synthesized with high production throughput.

Polycyclic Arenes Dihydrodinaphthopentacene‐based Hole‐Transporting Materials for Perovskite Solar Cells Application

“…[29] C1 exhibited a higher hole mobility (9.77 × 10 À 4 cm 2 V À 1 s À 1 ) than those of C2 (4.65 × 10 À 4 cm 2 V À 1 s À 1 ) that is attributed to the molecular ordering in the HTM layer, which was also consistent with the thinfilm morphology of C1 showed a more smooth surface when compared with C2. The hole mobility values of C1 and C2 are higher than that of spiro-OMeTAD (1.49 × 10 À 5 cm 2 V À 1 s À 1 ) [24] could be ascribed to the more planar polyaromatic hydrocarbon DHDNP backbone, which can affect the intermolecular interactions a certain extent. The better film-forming property is beneficial for hole transport process at the interface between the HTM and perovskite, resulting in better photovoltaic performance.…”

Dopant-free novel hole-transporting materials based on quinacridone dye for high-performance and humidity-stable mesoporous perovskite solar cells

“…Additionally strong H-bonding properties provide high charge transport abilities and electron deficient core (acceptor) conjugated backbone plays a role of an allowing a Donor-Acceptor-Donor (D-A-D) geometry, which has recently been shown to provide high performance and stability in PSCs. [26][27][28] In our current molecular engineering design, we used QA acceptor as core and ACE, TPA and DPA donor groups as end cappers. TPA and DPA moieties have already been widely used as end-capping groups in the design of organic HTMs for PSCs, and devices using such HTMs displayed not only very high efficiency but also superior stability.…”

Boosting inverted perovskite solar cell performance by using 9,9-bis(4-diphenylaminophenyl)fluorene functionalized with triphenylamine as a dopant-free hole transporting material

“…33 Apart from OLED applications, various fluorene derivative based HTMs for perovskite solar cells have been developed. [34][35][36][37][38][39][40][41][42][43][44][45][46] However, they rely on additives which damage the long-term stability of the devices and are mainly employed in conventional/regular (n-ip) structures. There are hardly any studies regarding fluorenebased HTMs fabricated for inverted devices.…”