Suppressing Phase Segregation in Triple Junction Perovskite Solar Cells

A pin-type tandem photovoltaic structure with improved stability under illumination, comprising a perovskite-based upper photovoltaic cell and a lower photovoltaic cell. The upper cell includes a buffer layer made of aluminum oxide with a thickness of 1-5 nm, deposited at a temperature of 25-150°C. The lower cell can be made from silicon, perovskite, or Cu(In,Ga)(S,Se)2. The buffer layer is produced by atomic layer deposition (ALD) at a temperature of 25-150°C.

Source

Multiple cation-doped perovskite compound for solar cells with improved stability and efficiency compared to conventional perovskite. The compound has a unique composition formula that allows avoiding segregation and phase separation when illuminated. It contains multiple cations like cesium (Cs), formamidinium (FA), and lead halide (PbX3) with a specific ratio. The Cs and FA doping balances the lattice strain and prevents segregation. The absence of methylammonium (MA) improves thermal stability. This compound provides a stable and efficient perovskite solar cell material.

Source

A method for preparing high-quality perovskite layers for solar cells, comprising incorporating a third component with a molecular size greater than a threshold value into the perovskite crystal structure. The third component, which can be an organic molecule or a substituted alkyl group, is located on the surface and/or grain boundary of the perovskite crystal and enhances passivation of defects and interfaces. The perovskite layer is then formed through a solution-based method, followed by annealing to remove solvent and crystallize the perovskite structure.

Source

Perovskite solar cells with high power conversion efficiency and long-term stability to ambient humidity and heat. The cells feature a 3D/2D perovskite heterojunction where the 2D perovskite layer is anchored to the 3D perovskite layer with oleylammonium-iodide molecules. This heterojunction is formed at the electron-selective interface, enabling efficient top-contact passivation and suppressing ion migration. The cells demonstrate a power conversion efficiency of 24.3% and retain >95% of their initial value after >1000 hours of damp-heat testing, meeting industry stability standards for photovoltaic modules.

Source

A solar cell with an energy-selective contact layer that enables hot carrier transport through a single material, eliminating the need for quantum dots or complex deposition processes. The energy-selective contact layer is formed from a low-dimensional perovskite material that selectively transports electrons or holes, enabling efficient hot carrier extraction and conversion.

Source

The rapid success achieved from perovskite solar cell has drawn great expectations for commercialization of next-generation photovoltaics. Among the various perovskite materials, the inorganic perovskite derivatives have been of particular interest, ascribed to its superior thermal and chemical stability, which is a crucial criterion for reliable long-term operation. Nonetheless, the development of the efficient inorganic perovskite solar cells has been lagged from its organicinorganic hybrid counterparts owing to the notorious phase-stability challenges associated with the formation of non-photoactive phases. The early progress of the inorganic perovskite solar cells has been centered on the stable perovskite phase-preparation and leads to the effective bulk management through intermediate engineering and compositional engineering strategies. Yet, challenges remain in securing the as-formed perovskite phase throughout the long-term operation. Accordingly, recent studies find interfacial modification strategies successful by constricting the phase-transformation channels in various ... Read More

Source

A method for preparing a solar cell with improved efficiency and stability, comprising forming a perovskite absorption layer with monocrystal perovskite particles arranged in a bonding matrix, where at least some particles have convex surfaces protruding from both sides of the matrix. The method further includes forming functional layers on the particle surfaces and carrier transport layers on the absorption layer surfaces to enhance carrier transport and reduce recombination.

Source

A perovskite solar cell with improved efficiency and stability, comprising a perovskite material with reduced crystal defects, achieved through the use of specific ionic compounds containing a five-membered heterocyclic ring as a passivation layer or additive. The compounds, represented by formulas (3) to (5), are designed to suppress and repair defects in the perovskite material, resulting in enhanced photovoltaic performance and stability.

Source

Perovskite solar cells with optimized grain boundary grooves (GBGs) that enhance opto-electronic properties through controlled void formation. The GBG structure, characterized by a specific side-angle between adjacent grains, is engineered to create a stable heterointerface between the perovskite layer and the substrate. This GBG architecture addresses the conventional issue of GB-induced delamination and void formation, while maintaining carrier injection and transport efficiency. The GBG side-angle range of 5-30 degrees is optimized for perovskite performance while minimizing GB-related degradation.

Source

All-perovskite tandem solar cells have exhibited greater potential in achieving power conversion efficiencies that are higher than those of single-junction devices. However, commonly used I/Br mixed wide-bandgap (WBG) perovskites, as an important component in the tandem device, always show a photoinduced halide phase segregation, which results in a large open-circuit voltage deficit and low photostability of the final all-perovskite tandem solar cells. In this work, we successfully stabilized the phase of the WBG perovskite by constructing a 2D wrapped 3D structure via introducing larger organic cation 2-(4-fluorophenyl)ethylamine hydroiodide, which has a high activation energy of ion migration to suppress the halide phase segregation. The phase-stable WBG perovskite solar cells achieved a high open-circuit voltage of 1.35 V with a power conversion efficiency of 19.4% and retain 92.1% of their initial value after 500 h of AM1.5G illumination. Finally, the constructed all-perovskite tandem solar cells achieved a high efficiency of 27%.

Source

The phase segregation of wide-bandgap perovskite is detrimental to a devices performance. We find that Sodium Benzenesulfonate (SBS) can improve the interface passivation of PTAA, thus addressing the poor wettability issue of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA). This improvement helps mitigate interface defects caused by poor contact between the perovskite and PTAA, reducing non-radiative recombination. Additionally, enhanced interface contact improves the crystallinity of the perovskite, leading to higher-quality perovskite films. By synergistically controlling the crystallization and trap passivation to reduce the phase segregation, SBS-modified perovskite solar cells (PSCs) achieved a power conversion efficiency (PCE) of 20.27%, with an open-circuit voltage (Voc) of 1.18 V, short-circuit current density (Jsc) of 20.93 mA cm2, and fill factor (FF) of 82.31%.

Source

With the rapid progress in a power conversion efficiency reaching up to 26.1%, which is among the highest efficiency for single-junction solar cells, organicinorganic hybrid perovskite solar cells have become a research focus in photovoltaic technology all over the world, while the instability of these perovskite solar cells, due to the decomposition of its unstable organic components, has restricted the development of all-inorganic perovskite solar cells. In recent years, Br-mixed halogen all-inorganic perovskites (CsPbI3xBrx) have aroused great interests due to their ability to balance the band gap and phase stability of pure CsPbX3. However, the photoinduced phase segregation in lead mixed halide perovskites is still a big burden on their practical industrial production and commercialization. Here, we demonstrate inhibited photoinduced phase segregation all-inorganic CsPbI1.2Br1.8 films and their corresponding perovskite solar cells by incorporating a 1-butyl-1-methylpiperidinium tetrafluoroborate ([BMP]+[BF4]) compound into the CsPbI1.2Br1.8 films. Then, its effect on the pero... Read More

Source

Solar battery with improved thermal durability, comprising a perovskite compound photoelectric conversion layer, an intermediate layer containing a heterocyclic compound with a six-membered ring having lone pairs at the 1- and 4-positions, and a second electrode. The heterocyclic compound terminates X-site vacancies in the perovskite compound, forming strong bonds between the lone pairs and B ions that stabilize the perovskite structure and enhance thermal resistance.

Source

Perovskite solar cells (PSCs) that incorporate both two-dimensional (2D) and three-dimensional (3D) phases possess the potential to combine the high stability of 2D PSCs with the superior efficiency of 3D PSCs. Here, we demonstrated in situ phase reconstruction of 2D/3D perovskites using a 2D perovskite single-crystal-assisted method. A gradient phase distribution of 2D RP perovskites was formed after spin-coating a solution of the 2D RuddlesdenPopper (RP) perovskite single crystal, (DFP)2PbI4, onto the 3D perovskite surface, followed by thermal annealing. The resulting film exhibits much reduced trap density, increased carrier mobility, and superior water resistance. As a result, the optimized 2D/3D PSCs achieved a champion efficiency of 24.87% with a high open-circuit voltage (VOC) of 1.185 V. This performance surpasses the control 3D perovskite device, which achieved an efficiency of 22.43% and a VOC of 1.129 V. Importantly, the unencapsulated device demonstrates significantly enhanced operational stability, preserving over 97% of its original efficiency after continuous light ir... Read More

Source

Tandem photovoltaic device comprising a silicon-based sub-cell and a perovskite-based sub-cell, where the perovskite sub-cell includes a N-type layer formed from metal oxide nanoparticles with controlled carbon content, achieved through a low-temperature process involving dispersion deposition and carbon elimination treatment. The N-type layer is characterized by a reduced carbon content of less than 20% and a roughness average value of 3-10 nm. The device exhibits improved photovoltaic conversion efficiency compared to conventional tandem devices.

Source

The recent tremendous progress in monolithic perovskite-based double-junction solar cells is just the start of a new era of ultra-high-efficiency multi-junction photovoltaics. We report on triple-junction perovskiteperovskitesilicon solar cells with...

Source

Abstract Widebandgap metal halide perovskites have demonstrated promise in multijunction photovoltaic (PV) cells. However, photoinduced phase segregation and the resultant low opencircuit voltage ( V oc ) have greatly limited the PV performance of perovskitebased multijunction devices. Here, a alloying strategy is reported to achieve uniform distribution of triple cations and halides in widebandgap perovskites by doping Rb + and Cl with small ionic radii, which effectively suppresses halide phase segregation while promoting the homogenization of surface potential. Based on this strategy, a V oc of 1.33 V is obtained from singlejunction perovskite solar cells, and a V OC approaching 3.0 V and a power conversion efficiency of 25.0% (obtained from reverse scan direction, certified efficiency: 24.19%) on an 1.04 cm 2 photoactive area can be achieved in a perovskite/perovskite/cSi triplejunction tandem cell, where the certification efficiency is by far the greatest performance of perovskitebased triplejunction tandem solar cells. This work overcomes the performance deadlock of ... Read More

Source

Wide-bandgap (WB) mixed-halide perovskite solar cells (PSCs) play a crucial role in perovskite-based tandem solar cells (TSCs), enabling them to exceed the Shockley-Queisser limits of single-junction solar cells. Nonetheless, the lack of stability in WB perovskite films due to photoinduced phase segregation undermines the stability of WB PSCs and their TSCs, thus impeding the commercialization of perovskite-based TSCs. Many efforts have been made to suppress photoinduced phase segregation in WB perovskite films and significant progresses have been obtained. In this review, we elaborate the mechanisms behind photoinduced phase segregation and its impact on the photovoltaic performance and stability of devices. The importance role of advanced characterization techniques in confirming the photoinduced phase segregation are comprehensively summarized. Beyond that, the effective strategies to alleviate photoinduced phase segregation in WB mixed halide PSCs are systematically assessed. Finally, the prospects for developing highly efficient and stable WB PSCs in tandem application are also ... Read More

Source

Abstract Mixedhalide perovskites show promising applications in tandem solar cells owing to their adjustable bandgap. One major obstacle to their commercialization is halide phase segregation, which results in large opencircuit voltage deficiency and J V hysteresis. However, the ambiguous interplay between structural origin and phase segregation often results in aimless and unspecific optimization strategies for the device's performance and stability. An atomic scale is directly figured out the abundant RuddlesdenPopper antiphase boundaries (RPAPBs) within a CsPbIBr 2 polycrystalline film and revealed that phase segregation predominantly occurs at RPAPBenriched interfaces due to the defectmediated lattice strain. By compensating their structural lead halide, such RPAPBs are eliminated, and the decreasing of strain can be observed, resulting in the suppression of halide phase segregation. The present work provides the deciphering to precisely regulate the perovskite atomic structure for achieving photostable mixed halide widebandgap perovskites of highefficiency tandem s... Read More

Source

Perovskitebased triplejunction solar cells have recently gained significant attention and are rapidly developing, thanks to the insights gained from the advancement in its dualjunction counterparts. However, employing perovskite materials in multijunction solar cells with more than two junctions brings new challenges that have not yet been addressed. One aspect is the possibility of reverse bias breakdown of perovskite subcells during operation of the triplejunction device. This is more relevant for triplejunction solar cells because a higher reverse voltage might drop at perovskite subcells compared to the case of dualjunction solar cells. Herein, the breakdown voltages of the two perovskite subcells in perovskite/perovskite/silicon triplejunction solar cells are determined by progressively increasing the reverse bias applied to the subcells in a singlejunction architecture during currentvoltage measurements and monitoring the appearance of shunts using illuminated lockin thermography measurements. Furthermore, to analyze the effect on the final triplejunction solar cell,... Read More

Source