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An open-cage bis[60]fulleroid (OC) was applied as an electron transport material (ETM) in tin (Sn) halide perovskite solar cells (PSCs). Due to the reduced offset between the energy levels of Sn-based perovskites and ETMs, the power conversion efficiency (PCE) of Sn-based PSCs with OC reached 9.6% with an open-circuit voltage (VOC) of 0.72 V. Additionally, OC exhibited superior thermal stability and provided 75% of the material without decomposition after vacuum deposition. The PSC using vacuum-deposited OC as the ETM could afford a PCE of 7.6%, which is a big leap forward compared with previous results using vacuum-deposited fullerene derivatives as ETMs. [ABSTRACT FROM AUTHOR]

Next‐generation photovoltaic technologies such as dye‐sensitized solar cells, organic thin‐film photovoltaics and perovskite solar cells are promising to efficiently harvest ambient light energy. However, more and deeper understanding of their photovoltaic characteristics is essential to create new applications under room light illumination. In this study, for the first time, the difference in temperature coefficients and angular dependence of photovoltaic parameters for the large‐area devices are investigated systematically under the compact fluorescent lamp and light‐emitting diode light. These emerging photovoltaic devices, compared with the single crystalline silicon solar cells, not only have higher open‐circuit voltage (up to approximate 1 V) and better power conversion efficiency (in the range of 9.2% ~ 22.6%) but also exhibit less temperature dependent voltage and output power (< −0.6% °C−1), as well as broader angular response (over 75 degrees). The state‐of‐the‐art dye‐sensitized and organic thin‐film devices also show advantageously positive temperature coefficients of current, and the latter even has positive thermal dependence of fill factor. These features suggest the next‐generation photovoltaic devices are more favorable than the conventional crystalline silicon solar cells for real‐life indoor applications. [ABSTRACT FROM AUTHOR]

Two linear organic A–D–A molecules ( DTPT and DTPTT ) comprised of electron-donating (D) coplanar heteroacenes as core end-capping with electron-accepting (A) dicyanovinylene were investigated as electron donor materials in organic photovoltaic (OPV) applications. The photophysical and electrochemical properties of these two dyes were examined. The A–D–A configuration renders these two molecules to have intense and red-shifted absorption characteristics for better light-harvesting (higher photocurrent density), while retaining relatively low HOMO energy levels for keeping sufficiently high open circuit voltage ( V oc ) in OPV. The optical constants and molecular orientation of thin films were acquired with variable-angle spectroscopic ellipsometry (VASE). Due to the anisotropic behavior observed in thin film, these two organic donors were firstly adopted to combine with electron acceptor C 60 in a vacuum-processed planar heterojunction (PHJ) solar cells. The optimized DTPT -based PHJ device yielded a PCE of 3.01%, whereas the PHJ device based on DTPTT , delivered an inferior PCE of 1.70%. The exciton diffusion length extracted from spectrum-response modeling of PHJ devices is ∼5 nm and ∼4 nm for DTPT and DTPTT , respectively. Replacement of C 60 with C 70 for a better spectral response in 400–500 nm, planar-mixed heterojunction (PMHJ) SMOSCs without a thin donor layer in between the active layer and MoO 3 was found to produce optimum device results. The optimized DTPTT -based device showed a PCE of 3.02%, while the shorter counterpart DTPT delivered a PCE up to 5.64%. [ABSTRACT FROM AUTHOR]

The use of photovoltaic cells with an organometallic perovskite as the active layer for indoor dim-light energy harvesting is evaluated. By designing the electron-transporting materials and fabrication processes, the traps in the perovskite active layers and carrier dynamics can be controlled, and efficient devices are demonstrated. The best-performing small-area perovskite photovoltaics exhibit a promising high power conversion efficiency up to 27.4%, no hysteresis behavior, and an exceptionally low maximum power point voltage variation of 0.1 V under fluorescent lamp illumination at 100-1000 lux. The 5.44 cm² large-area device also shows a high efficiency of 20.4% and a promising long-term stability. Compared with the most efficient inorganic and organic solar cells nowadays, the competitive efficiency, low fabrication cost, and low raw material costs make perovskite photovoltaics ideal for indoor light harvesting and as Internet of Things power provider. [ABSTRACT FROM AUTHOR]

Vacuum Fabrication: Efficient Cesium Lead Halide Perovskite Solar Cells through Alternative Thousand-Layer Rapid Deposition (Adv. Funct. Keywords: alternative deposition; cesium; perovskite solar cells; vacuum deposition Alternative deposition, cesium, perovskite solar cells, vacuum deposition. [Extracted from the article]

The novel growth of cesium lead halide perovskite thin films, which are prepared through thousand‐layer rapid alternative deposition, is performed by developing an active perovskite film consisting of a layer‐by‐layer structure. This method is considerably more difficult to be implemented from the solution process. The obtained thin film morphology and characteristics are distinguished from that of the traditional a few layers and two‐material codeposition. These alternative deposited perovskites are integrated with vacuum‐deposited carrier‐transporting layers and electrodes, and all vacuum‐sublimed perovskite solar cells exhibit an outstanding power conversion efficiency of 13.0%. The use of these devices for environmental light energy harvesting provides a power conversion efficiency of 33.9% under fluorescent light illumination of 1000 lux. [ABSTRACT FROM AUTHOR]

[Display omitted] • First investigation for the panchromatic absorption from Sb based perovskites by using complimentary absorbing ETLs. • Adduct formation for ITIC molecule with Cs 3 Sb 2 I 9 have also been investigated. • Optical simulations were conducted to calculate the contribution to current density from each layer. • Best solar cell efficiency of 3.2% for inorganic Sb based perovskite was achieved. • A 3 B 2 X 9 perovskite is studied under indoor light illumination and an efficiency of 9.2% was achieved under 1000 Lux. The search for stable alternative lead-free perovskites has identified all-inorganic antimony/bismuth halide derivatives as promising materials. Despite attractive optoelectronic properties, their wider band gaps and poor morphological control have greatly limited their solar device performance. In this study, we used the indacenodithiophene-based organic acceptor (ITIC) as a Lewis base to improve the morphology of Cs 3 Sb 2 I 9 films and also as an electron transport layer to form a complimentary heterojunction, and, thereby, enhance the performance of Cs 3 Sb 2 I 9 solar cells. The presence of cyano and carbonyl groups in ITIC modulated the rate of crystallization of Cs 3 Sb 2 I 9 and improved its optoelectronic properties. The panchromatic absorption of the Cs 3 Sb 2 I 9 /ITIC heterostructure provided a power conversion efficiency of 3.25% in inverted solar cell structure under 1-sun irradiation. This enhanced performance when using a complimentary absorption strategy suggests a new pathway for developing wider-band-gap lead-free perovskite derivatives for solar cell applications. Moreover, the optimized Cs 3 Sb 2 I 9 /ITIC heterostructure–based solar cell achieved a PCE of 9.2% under indoor illumination at 1000 lx, highlighting the potential use of such devices in indoor applications. [ABSTRACT FROM AUTHOR]