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The perovskite-inspired Cu2AgBiI6 (CABI) material has been gaining increasing momentum as photovoltaic (PV) absorber due to its low toxicity, intrinsic air stability, direct bandgap, and a high absorption coefficient in the range of 105 cm−1. However, the power conversion efficiency (PCE) of existing CABI-based PVs is still seriously constrained by the presence of both intrinsic and surface defect

The stability of perovskite solar cells (PSCs) is greatly affected by the interface between the perovskite active layer and the hole transport material (HTM). The rational design of HTMs with effective anchoring to the perovskite surface is an emerging elegant strategy to promote compact and ordered interfaces that lead to highly efficient and stable PSCs. Herein, we propose two fluorene-based HTM

Designing dopant-free small-molecule hole transport materials (HTMs) with self-assembly behavior via noncovalent interactions is considered as one effective strategy to achieve high-performance inverted perovskite solar cells (PSCs). Herein, two donor-π bridge-donor (D–π–D) HTMs are presented, TPASF and TPAOF, containing 3,6-dimethoxythieno[3,2-b]thiophene as a core part with 3-fluoro-N,N-bis(4-(m

Cesium manganese chloride (CsMnCl3) nanocrystals (NCs) have recently been recognized as potential lead-free perovskite candidates for red emission. To ascertain how the luminescence properties depend on the NC structures formed under different synthesis conditions, we synthesized CsMnCl3NCs in two polymorphic structures, namely, cubic (c-CsMnCl3) and rhombohedral (r-CsMnCl3), by tuning the reactio

Antimony-based perovskite-inspired materials (PIMs) are solution-processable halide absorbers with interesting optoelectronic properties, low toxicity, and good intrinsic stability. Their bandgaps around 2 eV make them particularly suited for indoor photovoltaics (IPVs). Yet, so far only the fully inorganic Cs3Sb2ClxI9−x composition has been employed as a light-harvesting layer in IPVs. Herein, th

To date, n-type semiconductor designs are less investigated than their p-type counterparts, due to the fact that the charge transport mobility and the stability of the n-type materials are generally lower than those of the p-type ones. Well-defined n-type semiconductors often require low lowest unoccupied molecular orbital (LUMO) levels that facilitate the electron injection from the electrode int

Lead-free Sn(II) based, CsSn2Br5, perovskite nanocubes were synthesized using a modified hot-injection method by tuning the injection temperature and reaction conditions. The formation of Sn(IV) based, Cs2SnBr6, perovskite nanocrystals (PNCs) from CsSn2Br5 perovskite nanocubes was observed. X-ray diffraction measurements revealed that oxygen or water molecules in air gradually react with CsSn2Br5

Recently, metal halide perovskites have been hailed by many as the “wonder” semiconductor for photovoltaics, because of their outstanding optoelectronic properties and facile solution processability. Perovskite-based solar cells have reached a power conversion efficiency record above 25% in just more than a decade of research. Halide perovskite semiconductors constitute a wide family of materials

To date, most of the reported conjugated materials are p-type semiconductors, while the advances in n-type or ambipolar conjugated materials greatly fall behind those in p-type counterparts. Well-defined n-type semiconductors should possess suitable electron-deficient groups and relatively low lowest unoccupied molecular orbitals (LUMO) levels that facilitate the electron injection and stabilize t

Although many dopant-free hole transport materials (HTMs) for perovskite solar cells (PSCs) have been investigated in the literature, novel and useful molecular designs for high-performance HTMs are still needed. In this work, a hydrogen-bonding association system (NH···CO) between amide and carbonyl is introduced into the pure HTM layer. Our study demonstrates that the hydrogen-bonding associatio

Currently, a high efficiency single layer metal halide perovskite solar cell employs a TiO2 mesoporous layer as an electron transporting material and spiro-OMeTAD as a hole transporting material. The efficient charge carrier separation and retarded interfacial charge recombination are expected to achieve a high solar to energy conversion efficiency. In this presentation, we will demonstrate how st

Designing a hole-transport material (HTM) that guarantees effective hole transport while self-assembling at the perovskite|HTM interface with the formation of an ordered interlayer, has recently emerged as a promising strategy for high-performance and stable perovskite solar cells (PSCs). Hydrogen bonding (HB) is a versatile multi-functional tool for the design of small molecular HTMs. However, to

Realizing ordered structures at the molecular level is a key approach to increase the charge mobility of organic semiconductors. However, the typical solution-based methods employed for the processing make the achievement of well-organized organic nanostructures difficult with the favored formation of disordered assemblies. To realize well-ordered thin films, one needs to design conjugated materia

Lead-free perovskite-inspired materials (PIMs) are gaining attention in optoelectronics due to their low toxicity and inherent air stability. Their wide bandgaps (≈2 eV) make them ideal for indoor light harvesting. However, the investigation of PIMs for indoor photovoltaics (IPVs) is still in its infancy. Herein, the IPV potential of a quaternary PIM, Cu2AgBiI6 (CABI), is demonstrated upon control

The design and synthesis of three star-shaped nonfullerene (NFA) acceptors, TPA-2T-INCN, TPA-2T-BAB, and TPA-T-INCN, based on a triphenylamine (TPA) core and linked through π-conjugated thiophene (T) spacers to different terminal units (3-oxo-2,3-dihydro-1H-inden-1-ylidene) malononitrile, INCN, and 1,3-dimethylbarbituric acid, BAB), are reported. These materials are blended with the widely used po

Despite the outstanding power conversion efficiency of triple-cation perovskite solar cells (PSCs), their low long-term stability in the air is still a major bottleneck for practical applications. The hygroscopic dopants traditionally used in hole transport materials (HTMs) severely degrade the perovskite film. The p-type F4-TCNQ doping of the well-known spiro-OMeTAD HTM enables hydrophobicity-ind

It is universally acknowledged that highly photosensitive transistors are strongly dependent on the high carrier mobility of polymer-based semiconductors. However, the polymer π–π stacking and aggregation, required to increase the charge mobility, conversely inhibit the dissociation of photogenerated charge carriers, in turn accelerating the geminate recombination of electron-hole pairs. To explor

Lead-based halide perovskite nanocrystals (NCs) are recognized as emerging emissive materials with superior photoluminescence (PL) properties. However, the toxicity of lead and the swift chemical decomposition under atmospheric moisture severely hinder their commercialization process. Herein, we report the first colloidal synthesis of lead-free Cs4CuIn2Cl12 layered double perovskite NCs via a faci

In this work, we introduce P3HT (poly(3-hexylthiophene-2,5-diyl)) as an efficient hole transport material (HTM) for lead-free Cs3Sb2I9perovskite-inspired solar cells. The P3HT doubles the power conversion efficiency (PCE) of the solar cells (PCE = 2.5% for the champion device) by improving all of the figures of merit: the fill factor, open-circuit voltage, and the short-circuit current. The maximu

Semiconductor quantum dot (QD) sensitization is one of the most attractive structures to employ QDs for photovoltaic application. The function of QD sensitized solar cells (QDSSC) is controlled by the interfacial charge transfer dynamics. Here we employ transient absorption spectroscopy (TAS) to assess charge transfer dynamics at CdS QD/TiO2 interface, and correlate their dynamics with their solar