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In order to fabricate nickel oxide (NiOX)-based perovskite solar cells with high efficiency and stability, adverse reaction and lattice mismatch are two urgent problems to be overcome. In this respect, interface engineering was carried out by multi-layer passivation NiOX HTLs (NiOX/2PACz/Poly-TPD/PEAI) to provide optimized interface contact between NiOX and perovskite, ameliorate band alignment, and saturate the defect states. Application of 2PACz avoids direct contact of the hydroxyl groups (which causes degeneration of a device), improves conductivity, and reduces interfacial defects. The poly-TPD modification can provide an appropriate band alignment at the interface of NiOX/perovskite. PEAI was used to modify the Poly-TPD surface, and its −NH3 group can passivate unbonded Pb ions of perovskite. Thus, compared with previously reported single-function passivation materials, the multilayer passivation proposed in this paper integrates multiple functions. As a result, the NiOX/2PACz/Poly-TPD/PEAI-based wide bandgap PSCs obtain a champion power conversion efficiency (PCE) of 20.21% and maintain over 95% of their initial PCE values after storage in a nitrogen atmosphere for 1000 h. This finding provides a practical approach for fabricating high-performance regular PSCs with NiOX-based HTLs and supports their commercialization. [ABSTRACT FROM AUTHOR]

Although perovskite solar cells (PSCs) based on SnO2 have reached a power conversion efficiency (PCE) over 25%, large-scale fabrication remains the main obstacle to the commercialization of PSCs. Therefore, considering the process compatibility, low-temperature processing and large-area fabrication technologies have received widespread attention as those are ideal for upscaling of single and tandem devices. Herein, we demonstrated an effective atomic layer deposition (ALD) process by using H2O2 as an oxygen source and the deposition temperatures can be lowered up to 50 °C due to the high activity of H2O2. The low temperature deposition enables conformal coverage of the substrate and results in a pinhole-free film with high optical transmittance, excellent electron extraction properties, and large area uniformity. Notably, a high PCE of 20.70% is achieved for single junction PSCs based on ALD-SnO2 (50 °C). When the ALD-SnO2 applied to p-i-n structure perovskite/silicon heterojunction tandem solar cell, an efficiency of 26.67% was obtained. The results demonstrate the potential of the low-temperature ALD processed metal oxide for large-scale manufacturing of optoelectronic devices with competitive performances. [ABSTRACT FROM AUTHOR]

In recent years, perovskite/silicon tandem solar cells (PK/c‐Si tandem) have demonstrated high power conversion efficiency (PCE) and demonstrated great application potential in photovoltaic (PV) systems. However, the PCE of PK/c‐Si tandem devices is still below the theoretical limit. From a broader perspective, their poor stability and difficulty in large‐area realization are crucial barriers for commercial viability. In this report, the detailed constraints facing high PCE of tandem devices and the corresponding solutions are discussed. The authors propose that the main obstacle comes from the limitation of the perovskite top cell. However, careful understanding of the optical and electrical properties of each functional layer is expected to be the core process to further promote efficiency. Regarding the environmental and intrinsic instability issues, encapsulation is considered to be the most effective method to address environmental instability. Preventing ion migration is one of the fundamental methods to eliminate intrinsic instability. It is believed that low dimensional perovskite materials will become a competitive solution to simultaneously solve these two instabilities. Finally, some suggestions for reducing costs and preparation of PK/c‐Si tandem on a large‐scale are also discussed which provides guidance for further boosting the development of PK/c‐Si tandem. [ABSTRACT FROM AUTHOR]

Outstanding performance of perovskite solar cells (PSCs) is closely linked to the optoelectrical properties of charge transporting layers. Herein, amino trimethylene phosphonic acid (ATMP) and KOH are mixed (ATMP‐K) and incorporated in a SnO2 precursor solution to significantly improve the performance of the electron transport layer (ETL) SnO2 in PSCs. Combining density functional theory (DFT) calculations and experiments, it is demonstrated that ATMP‐K effectively passivates the oxygen vacancy and reduces the hydroxyl groups on the surface of SnO2, resulting in a larger perovskite grain size and better energy‐level alignment with perovskites. ATMP‐K boosts the power conversion efficiency (PCE) of the PSCs from 20.99% to 23.52%. When applying in a perovskite/silicon heterojunction tandem solar cell, the device delivers an efficiency up to 24.75% with a high VOC of 1.94 V, compared with 22.67% and 1.85 V of the reference cells. Furthermore, ATMP‐K‐modified PSCs also show extraordinary ability to absorb Pb2+ ions after their degradation in water, offering a facile strategy for reducing Pb leakage. [ABSTRACT FROM AUTHOR]

The efficiency of perovskite (PVK)/silicon tandem solar cells have the potential to beyond the Shockley–Queisser limit of single‐junction solar cell and the theoretical efficiency can reach over 35%. Improving the quality of PVK film can reduce nonradiative charge recombination. Herein, MACl is added to the PVK precursor, compared with the control cell, adding MACl can assist the vertical crystallization of PVK film, accelerates carrier vertical transport, reduces bulk defects in the active layer. Moreover, MACl can upshift the valence band energy level, making it better band alignment with hole‐transport layer. As a result, the fill factor (FF) and open‐circuit voltage (VOC) are improved with MACl addition. The champion MACl‐added PVK solar cell with 1.67 eV bandgap achieves an efficiency of 18.94% and a VOC of 1.225 V. Using the optimized wide bandgap PVK solar cells to fabricate the rear‐textured monolithic PVK /silicon heterojunction tandem solar cells, a champion efficiency of 24.16% and a VOC of 1.93 V are obtained. It is demonstrated that the control of PVK crystals vertical orientation provides an effective strategy for improving the efficiency of PVK‐based solar cells. [ABSTRACT FROM AUTHOR]

A novel three-dimensional graphene-like networks material (3D-GLN) exhibiting the hierarchical porous structure was fabricated with a large-scale preparation method by employing an ion exchange resin as a carbon precursor. 3D-GLN was first studied as the effective microwave absorbing material. As indicated from the results of the electromagnetic parameter tests, and the minimum reflection loss (RL) of the 3D-GLN reached −34.75 dB at the frequency of 11.7 GHz. To enhance the absorption performance of the nonmagnetic 3D-GLN, the magnetic Fe3O4 nanoparticles were loaded on the surface of the 3D-GLN by using the hydrothermal method to develop the 3D-GLN/Fe3O4 hybrid. The hybrid exhibited the prominent absorbing properties. Under the matching thickness of 3.0 mm, the minimum RL value of hybrid reached −46.8 dB at 11.8 GHz. In addition, under the thickness range of 2.0–5.5 mm, the effective absorption bandwidth (RL < 10 dB) was 13.0 GHz, which covered part of the C-band and the entire X-band, as well as the entire Ku-band. The significant microwave absorption could be attributed to the special 3D network structure exhibited by the hybrid and the synergistic effect exerted by the graphene and the Fe3O4 nanoparticles. As revealed from the results, the 3D-GLN/Fe3O4 hybrid could be a novel microwave absorber with promising applications. [ABSTRACT FROM AUTHOR]

The interface between the perovskite layer and electron transporting layer is a critical determinate for the performance and stability of perovskite solar cells (PSCs). The heterogeneity of the interface critically affects the carrier dynamics at the buried interface. To address this, a bridging molecule, (2-aminoethyl)phosphonic acid (AEP), is introduced for the modification of SnO 2 /perovskite buried interface in n-i-p structure PSCs. The phosphonic acid group strongly bonds to the SnO 2 surface, effectively suppressing the surface carrier traps and leakage current, and uniforming the surface potential. Meanwhile, the amino group influences the growth of perovskite film, resulting in higher crystallinity, phase purity, and fewer defects. Furthermore, the bridging molecules facilitate the charge extraction at the interface, as indicated by the femtosecond transient reflection (fs-TR) spectroscopy, leading to champion power conversion efficiency (PCE) of 26.40% (certified 25.98%) for PSCs. Additionally, the strengthened interface enables improved operational durability of ≈1400 h for the unencapsulated PSCs under ISOS-L-1I protocol., (© 2024 Wiley‐VCH GmbH.)

Polycrystalline perovskite films fabricated on flexible and textured substrates often are highly defective, leading to poor performance of perovskite devices. Finding substrate-tolerant perovskite fabrication strategies is therefore paramount. Herein, this study shows that adding a small amount of Cadmium Acetate (CdAc 2 ) in the PbI 2 precursor solution results in nano-hole array films and improves the diffusion of organic salts in PbI 2 and promotes favorable crystal orientation and suppresses non-radiative recombination. Polycrystalline perovskite films on the flexible substrate with ultra-long carrier lifetimes exceeding 6 µs are achieved. Eventually, a power conversion efficiency (PCE) of 22.78% is obtained for single-junction flexible perovskite solar cells (FPSCs). Furthermore, it is found that the strategy is also applicable for textured tandem solar cells. A champion PCE of 29.25% (0.5003 cm 2 ) is demonstrated for perovskite/silicon tandem solar cells (TSCs) with CdAc 2 . Moreover, the un-encapsulated TSCs maintains 109.78% of its initial efficiency after 300 h operational at 45 °C in a  nitrogen atmosphere. This study provides a facile strategy for achieving high-efficiency perovskite-based solar cells., (© 2023 Wiley-VCH GmbH.)

Nickel oxide (NiO x ) is an attractive hole-transport material for efficient and stable p-i-n metal-halide perovskite solar cells (PSCs). However, an undesirable redox reaction occurs at the NiO x /perovskite interface, which results in a low open-circuit voltage (V OC ), instability, and phase separation of the NiO x -based wide-bandgap perovskite (Br > 20%). In order to simultaneously address the abovementioned phase separation problem and redox chemistry at the perovskite/NiO x interface, the bandgap is widened from 1.64 to 1.67 eV by adding inorganic CsPbCl 3 -clusters (3 mol%) to the Cs 22 Br 15 perovskite precursor solution. Moreover, adding extra 2 mol% CsCl enriches the NiO x /perovskite interface with Cl, thereby preventing the redox reaction at the interface, while controlling the Br content to within 15% improves the photostability of the wide-bandgap perovskite. Consequently, the power conversion efficiency (PCE) of a single-junction p-i-n PSC increases from 17.82% to 19.76%, which leads to the fabrication of highly efficient monolithic p-i-n-type NiO x -based perovskite/silicon tandem solar cells with PCEs of up to 27.26% (certified PCE: 27.15%). The perovskite to an n-i-p-type perovskite/silicon tandem solar cell is also applied to deliver a V OC of 1.93 V and a final efficiency of 25.5%. These findings provide critical insight into the fabrication of highly efficient and stable wide-bandgap perovskites., (© 2022 Wiley-VCH GmbH.)