Functional Additive Incorporation Enhances the Performance of Semi-Transparent Perovskite Solar Cells
ACS Energy Letters (2025)
Abstract:
Semi-transparent perovskite solar cells (ST-PSCs) have shown great potential in building-integrated photovoltaics. However, the performance of ST-PSCs is still far from achieving their true potential. Herein, a functional additive, [4-(trifluoromethyl)phenyl] sulfonyl chloride (TFBSC), is incorporated into the perovskite precursor solution to regulate the crystallization process and reduce defects in the perovskite films. The addition of TFBSC improves the perovskite film morphology and increases the charge carrier lifetime and photoluminescence quantum efficiency, compared with the control perovskite films. As a result, the champion device modified with TFBSC shows a power conversion efficiency (PCE) of 14.75% with a light utilization efficiency (LUE) of 3.92%, whereas the control device shows PCE and LUE values of 10.71% and 2.96%, respectively. Moreover, the unencapsulated TFBSC-modified device retains 鈭90% of its initial PCE after 1500 h of storage under ambient conditions (relative humidity of 鈭30%鈥40%). These findings could provide new avenues to develop high performance ST-PSCs for smart building applications.Critical Assessment of Contact Resistance and Mobility in Tin Perovskite Field-Effect Transistors
Advanced Electronic Materials 11:15 (2025)
Abstract:
Recent reports highlight the potential of tin-based perovskite semiconductors for high-performance p-type field-effect transistors (FETs) with mobilities exceeding 20聽cm2聽V鈦宦孤爏鈦宦. However, these high mobilities鈥攐ften obtained via two-probe (2P) methods on devices with small channel length-to-width ratios (L/W聽<聽0.5) operating in the saturation regime at high drain-source currents鈥攔aise concerns about overestimation due to contact resistance and non-ideal FET characteristics. Here, gated four-point probe (4PP) FET measurements is performed on Hall bar devices (L/W = 5) of CsUnraveling low-temperature structural and dielectric characteristics in lead-free bismuth halide perovskites
Journal of Materials Chemistry C 13:2 (2024) 918-927
Abstract:
Bismuth halide perovskite crystals have garnered a lot of interest lately because of their superior optoelectronic qualities, affordability, and ease of processing. Nonetheless, most of the research has concentrated on their room-temperature characteristics, leaving their low-temperature behavior largely unknown. Here, we have investigated the low-temperature behavior of bismuth halide perovskite crystals to understand their structural and dielectric characteristics. The low-temperature X-ray diffraction pattern revealed a sharp phase transition in MASubstitution of lead with tin suppresses ionic transport in halide perovskite optoelectronics.
Energy and Environmental Science Royal Society of Chemistry 17:2 (2023) 760-769
Abstract:
Despite the rapid rise in the performance of a variety of perovskite optoelectronic devices with vertical charge transport, the effects of ion migration remain a common and longstanding Achilles' heel limiting the long-term operational stability of lead halide perovskite devices. However, there is still limited understanding of the impact of tin (Sn) substitution on the ion dynamics of lead (Pb) halide perovskites. Here, we employ scan-rate-dependent current-voltage measurements on Pb and mixed Pb-Sn perovskite solar cells to show that short circuit current losses at lower scan rates, which can be traced to the presence of mobile ions, are present in both kinds of perovskites. To understand the kinetics of ion migration, we carry out scan-rate-dependent hysteresis analyses and temperature-dependent impedance spectroscopy measurements, which demonstrate suppressed ion migration in Pb-Sn devices compared to their Pb-only analogues. By linking these experimental observations to first-principles calculations on mixed Pb-Sn perovskites, we reveal the key role played by Sn vacancies in increasing the iodide ion migration barrier due to local structural distortions. These results highlight the beneficial effect of Sn substitution in mitigating undesirable ion migration in halide perovskites, with potential implications for future device development.
Tailoring Interlayer Charge Transfer Dynamics in 2D Perovskites with Electroactive Spacer Molecules
J. Am. Chem. Soc. 2023, 145, 39, 21330鈥21343
Abstract:
The family of hybrid organic鈥搃norganic lead-halide perovskites are the subject of intense interest for optoelectronic applications, from light-emitting diodes to photovoltaics to X-ray detectors. Due to the inert nature of most organic molecules, the inorganic sublattice generally dominates the electronic structure and therefore the optoelectronic properties of perovskites. Here, we use optically and electronically active carbazole-based Cz-Ci molecules, where Ci indicates an alkylammonium chain and i indicates the number of CH2 units in the chain, varying from 3 to 5, as cations in the two-dimensional (2D) perovskite structure. By investigating the photophysics and charge transport characteristics of (Cz-Ci)2PbI4, we demonstrate a tunable electronic coupling between the inorganic lead-halide and organic layers. The strongest interlayer electronic coupling was found for (Cz-C3)2PbI4, where photothermal deflection spectroscopy results remarkably reveal an organic鈥搃norganic charge transfer state. Ultrafast transient absorption spectroscopy measurements demonstrate ultrafast hole transfer from the photoexcited lead-halide layer to the Cz-Ci molecules, the efficiency of which increases by varying the chain length from i = 5 to i = 3. The charge transfer results in long-lived carriers (10鈥100 ns) and quenched emission, in stark contrast to the fast (sub-ns) and efficient radiative decay of bound excitons in the more conventional 2D perovskite (PEA)2PbI4, in which phenylethylammonium (PEA) acts as an inert spacer. Electrical charge transport measurements further 91探花 enhanced interlayer coupling, showing increased out-of-plane carrier mobility from i = 5 to i = 3. This study paves the way for the rational design of 2D perovskites with combined inorganic鈥搊rganic electronic properties through the wide range of functionalities available in the world of organics.