Antimony selenide (Sb
Se
) has a one-dimensional (1D) crystal structure comprising of covalently bonded (Sb
Se
)
ribbons stacking together through van der Waals force. This special structure results ...in anisotropic optical and electrical properties. Currently, the photovoltaic device performance is dominated by the grain orientation in the Sb
Se
thin film absorbers. Effective approaches to enhance the carrier collection and overall power-conversion efficiency are urgently required. Here, we report the construction of Sb
Se
solar cells with high-quality Sb
Se
nanorod arrays absorber along the 001 direction, which is beneficial for sun-light absorption and charge carrier extraction. An efficiency of 9.2%, which is the highest value reported so far for this type of solar cells, is achieved by junction interface engineering. Our cell design provides an approach to further improve the efficiency of Sb
Se
-based solar cells.
Nanophotonic structures have attracted attention for light trapping in solar cells with the potential to manage and direct light absorption on the nanoscale. While both randomly textured and ...nanophotonic structures have been investigated, the relationship between photocurrent and the spatial correlations of random or designed surfaces has been unclear. Here we systematically design pseudorandom arrays of nanostructures based on their power spectral density, and correlate the spatial frequencies with measured and simulated photocurrent. The integrated cell design consists of a patterned plasmonic back reflector and a nanostructured semiconductor top interface, which gives broadband and isotropic photocurrent enhancement.
Although inorganic perovskite solar cells (PSCs) are promising in thermal stability, their large open‐circuit voltage (VOC) deficit and difficulty in large‐area preparation still limit their ...development toward commercialization. The present work tailors C60 via a codoping strategy to construct an efficient electron‐transporting layer (ETL), leading to a significant improvement in VOC of the inverted inorganic CsPbI2Br PSC. Specifically, tris(pentafluorophenyl)borane (TPFPB) is introduced as a dopant to lower the lowest unoccupied molecular orbital (LUMO) level of the C60 layer by forming a Lewis acidic adduct. The enlarged free energy difference provides a favorable enhancement in electron injection and thereby reduces charge recombination. Subsequently, a nonhygroscopic lithium salt (LiClO4) is added to increase electron mobility and conductivity of the film, leading to a reduction in the device hysteresis and facilitating the fabrication of a large‐area device. Finally, the as‐optimized inorganic CsPbI2Br PSCs gain a champion power conversion efficiency (PCE) of 15.19%, with a stabilized power output (SPO) of 14.21% (0.09 cm2). More importantly, this work also demonstrates a record PCE of 14.44% for large‐area inorganic CsPbI2Br PSCs (1.0 cm2) and reports the first inorganic perovskite solar module with the excellent efficiency exceeding 12% (10.92 cm2) by a self‐developed quasi‐curved heating method.
A Lewis acid tris(pentafluorophenyl)borane and nonhygroscopic lithium salt (LiClO4) codoping strategy is introduced to tailor C60 and fabricate highly efficient inorganic CsPbI2Br perovskite solar cells with reduced hysteresis. Consequently, square‐centimeter inorganic CsPbI2Br perovskite solar cells yield a record power conversion efficiency (PCE) of 14.44%. In addition, the first inorganic perovskite solar module with an efficiency exceeding 12% is reported, using a self‐developed quasi‐curved heating method.
We report on the design, fabrication, and measurement of ultrathin film a-Si:H solar cells with nanostructured plasmonic back contacts, which demonstrate enhanced short circuit current densities ...compared to cells having flat or randomly textured back contacts. The primary photocurrent enhancement occurs in the spectral range from 550 nm to 800 nm. We use angle-resolved photocurrent spectroscopy to confirm that the enhanced absorption is due to coupling to guided modes supported by the cell. Full-field electromagnetic simulation of the absorption in the active a-Si:H layer agrees well with the experimental results. Furthermore, the nanopatterns were fabricated via an inexpensive, scalable, and precise nanopatterning method. These results should guide design of optimized, non-random nanostructured back reflectors for thin film solar cells.
Long-term stability of perovskite solar cells appears to be the bottleneck that limits its large-scale industrialization. Herein, we innovatively introduce gallium( iii ) acetylacetonate (GaAA 3 ) as ...the precursor additive to in situ induce a metal–organic-complex monomolecular intermediate (GaAA 3 4 ), which allows to realize Cs x FA 1−x PbI 3 –GaAA 3 4 (0 < x < 1) hybrid perovskite materials. The formed hybrid perovskites are proven to possess a thus far unreported structure with Cs x FA 1−x PbI 3 core and GaAA 3 4 shell, and the presence of thin GaAA 3 4 shells remarkably enhances the hydrophobicity of the perovskite thin films. As a result of an effective passivation effect by the core/shell heterostructure, the formed perovskites demonstrate superior photoelectronic performance in comparison with the independent archetype 3-dimensional (3D) counterparts, e.g. , they show low defect-state density, strong luminescence, and long lifetime of photo-generation charge carriers, which finally result in a high power conversion efficiency of 18.24% for core–shell planar perovskite solar cells. Equally important, the stabilized power output (SPO) of the unencapsulated cell remains over 18% for 5 h in an adverse atmosphere with 50% relative humidity (RH). The present study provides a facile approach to fabricate core–shell perovskite solar cells with high efficiency and long-term stability against moisture.
Binary Sb2Se3 semiconductors are promising as the absorber materials in inorganic chalcogenide compound photovoltaics due to their attractive anisotropic optoelectronic properties. However, Sb2Se3 ...solar cells suffer from complex and unconventional intrinsic defects due to the low symmetry of the quasi‐1D crystal structure resulting in a considerable voltage deficit, which limits the ultimate power conversion efficiency (PCE). In this work, the creation of compact Sb2Se3 films with strong 00l orientation, high crystallinity, minimal deep level defect density, fewer trap states, and low non‐radiative recombination loss by injection vapor deposition is reported. This deposition technique enables superior films compared with close‐spaced sublimation and coevaporation technologies. The resulting Sb2Se3 thin‐film solar cells yield a PCE of 10.12%, owing to the suppressed carrier recombination and excellent carrier transport and extraction. This method thus opens a new and effective avenue for the fabrication of high‐quality Sb2Se3 and other high‐quality chalcogenide semiconductors.
An injection vapor deposition (IVD) technology is designed and demonstrated. The IVD produces compact antimony selenide (Sb2Se3) films with high orientation preference, fewer deep‐level trap levels, and suppressed non‐radiative recombination, achieving a record power conversion efficiency of 10.12% for Sb2Se3 photovoltaics.
Perovskite materials are drawing tremendous interest for photovoltaic solar cell applications, but are hampered by intrinsic material and device instability issues. Such issues can arise from ...environmental influences as well as from the chemical incompatibility of the perovskite layer with charge transport layers and electrodes used in the device stack. Several attempts have been made to address the instability issue, mostly concentrating on the substitution of the organic cations in the perovskite lattice, and on alternatives for the organic charge extraction layers, without laying much emphasis on stabilising the existing, conventional high efficiency methylammonium lead iodide/spiro-OMeTAD based devices. To address the latter issue, we utilized atomic layer deposition (ALD) as a straightforward and soft deposition process to conformally deposit Al 2 O 3 on top of the perovskite absorber. An ultra-thin ALD Al 2 O 3 film effectively protects the perovskite layer while it is sufficiently thin enough to provide a tunnel contact. The fabricated perovskite solar cells (PSCs) exhibit superior device performance with a stabilised power conversion efficiency (PCE) of 18%, a significant reduction in hysteresis loss, and enhanced long-term stability (beyond 60 days) as a function of the unencapsulated storage time in ambient air, under humidity conditions ranging from 40 to 70% at room temperature. PCE measurements after 70 days of humidity exposure show that the devices incorporating 10 cycles of ALD Al 2 O 3 could significantly retard the humidity-induced degradation thereby retaining about 60–70% of its initial PCE, while that of the reference devices drops to a remaining 12% of their initial PCE. This work successfully addresses and tackles the problem of the hybrid organic–inorganic IV-halide perovskite solar cell’s instability in a humid environment, and the key findings pave the way to the upscaling of these devices.
Since the 1970s, installed solar photovoltaic capacity has grown tremendously to 230 gigawatt worldwide in 2015, with a growth rate between 1975 and 2015 of 45%. This rapid growth has led to concerns ...regarding the energy consumption and greenhouse gas emissions of photovoltaics production. We present a review of 40 years of photovoltaics development, analysing the development of energy demand and greenhouse gas emissions associated with photovoltaics production. Here we show strong downward trends of environmental impact of photovoltaics production, following the experience curve law. For every doubling of installed photovoltaic capacity, energy use decreases by 13 and 12% and greenhouse gas footprints by 17 and 24%, for poly- and monocrystalline based photovoltaic systems, respectively. As a result, we show a break-even between the cumulative disadvantages and benefits of photovoltaics, for both energy use and greenhouse gas emissions, occurs between 1997 and 2018, depending on photovoltaic performance and model uncertainties.
The intrinsically weak bonding structure in halide perovskite materials makes components in the thin films volatile, leading to the decomposition of halide perovskite materials. The reactions within ...the perovskite film are reversible provided that components do not escape the thin films. Here, a holistic approach is reported to improve the efficiency and stability of PSMs by preventing the effusion of volatile components. Specifically, a method for in situ generation of channel barrier layers for perovskite photovoltaic modules is developed. The resulting PSMs attain a certified aperture PCE of 21.37%, and possess remarkable continuous operation stability for maximum power point tracking (MPPT) of T90 > 1100 h in ambient air, and damp heat (DH) tracking of T93 > 1400 h.
In response to the unique ion migration problem at the monolithic interconnection regions of the perovskite solar modules, this work proposes a method of in situ generation of PbOx barrier layers, effectively improving the efficiency and stability of perovskite solar modules.
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