Solar RRL最新文献

Tunnel oxide passivated contact (TOPCon) solar cells achieve efficiencies exceeding 26% by incorporating a heavily doped poly-Si layer with a tunnel oxide, with recent efforts focusing on enhancing the rear passivation structure. In industrial TOPCon cells, the high-temperature firing process during metal contact formation degrades the passivation quality of poly-Si/SiO_x contacts, necessitating improvements to maintain cell performance. While previous studies examine degradation factors related to the rear structure, research on mechanisms driven by the firing process remains limited. This study identifies how excess hydrogen, rather than phosphorus in-diffusion, degrades passivation quality by diffusing from SiN_x into SiO_x during the firing process. Thermal stress during the firing process dissociates c-Si/SiO_x bonds, while interstitial hydrogen accumulates at the SiO_x interface and forms hydrogen pores as defects, reducing passivation quality. To mitigate this, we introduce an Al₂O₃ layer as a hydrogen diffusion barrier, effectively preventing hydrogen diffusion into SiO_x. This approach increases the implied open-circuit voltage (iV_oc) after firing, achieving a record 729.8 mV with Al₂O₃/SiN_x double passivation layers. These findings advance the understanding of degradation mechanisms in industrial TOPCon solar cells during firing and offer practical strategies for optimizing industrial-scale solar cell manufacturing.

Poly(3-hexylthiophene) (P3HT) has attracted significant interest due to its cost-effective synthesis, high purity, and stable film properties. However, the efficiency of perovskite solar cells is limited by energy-level mismatches and nonradiative recombination at the P3HT/perovskite interface. In this study, we introduce the 2,7-dimetapyridinebenzo[4,5]thieno[3,2-b]benzofuran (Mpy-BTBF) small molecule, which features extended π-conjugation and lone pair electrons from oxygen and sulfur atoms. Incorporating Mpy-BTBF into P3HT (M-P3HT) improves charge transport and passivates iodine-related defects, achieving a power conversion efficiency (PCE) of 16.36%, surpassing the pristine P3HT-based device (14.49%). With further Li salts doping, the champion PCE increased to 21.24 from 17.30%. Finally, M-P3HT-based devices maintained over 70% of their efficiency after 600 h of aging at 60% relative humidity and 60°C.

Scaling up high-performance perovskite solar cells (PSCs) while avoiding losses in the power conversion efficiency (PCE) is a challenging task. Surface passivation of the perovskite film has been demonstrated as an effective strategy to mitigate PCE losses. However, there is limited research on scalable surface passivation techniques. Herein, we studied how to develop a slot-die coating technique applying for passivation layers to PSCs, which can be adapted for industrial-scale production. Molecular structure of passivators and coating parameters have been systematically optimized to achieve high-quality film morphology, which enable effectively inhibition of interface recombination. As a result, champion efficiencies of 22.4% for small-size solar cells (0.16 cm²) and 18.3% for solar modules (10.0 cm²) have been achieved with 4-bromophenethylammonium chloride. Moreover, the encapsulated solar cells retained 89% of their initial performance after continuous operation under 100 mW·cm² illumination for 400 h.

The development of efficient photothermal materials for solar steam generation (SSG) garners significant interest as a solution to the global clean water scarcity crisis. Photothermal properties of organic molecules can be fine-tuned by molecular design. Despite this fact, the use of organic small-molecular photothermal materials in SSG applications is seldom explored due to their limited optical absorption range for solar energy harvesting. In this research, 6,6,12,12-tetrakis(4-octylphenyl)dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene (DTIDT) is focused upon as the potent conjugated core unit, and the [2 + 2] cycloaddition–retroelectrocyclization (CA-RE) reaction is applied to introduce additional intramolecular charge-transfer chromophores. DTIDT derivatives exhibit broad optical absorption, weak photoluminescence, and high nonradiative decay rates, which are useful for efficient photothermal conversion. In addition, the DTIDT derivatives are placed on the top surface of a filter paper, and the SSG devices are fabricated as a Janus membrane to enhance the solar-to-vapor efficiency. The DTIDT derivatives produced by the [2 + 2] CA-RE exhibit a maximum efficiency of 78.3% under simulated sunlight irradiation for 30 min. The result suggests that the CA-RE reaction is an effective method for synthesizing organic photothermal materials tailored for SSG applications.

Solar energy, as a renewable resource, offers an excellent solution to the increasing global energy demand. Solar cells convert solar energy into electricity, prompting extensive research in this field in recent years. However, enhancing solar cell efficiency presents several challenges. Currently, solar cells can only utilize a limited portion of the solar spectrum, as most UV and infrared light remain unabsorbed. Additionally, UV light can compromise the stability of solar cells. Therefore, optimizing the utilization of solar photons across the spectrum is essential for improving both the efficiency and stability of these devices. Down-conversion (DC) technology, also known as quantum cutting, effectively enhances the spectral absorption of solar cells, thereby increasing their efficiency and stability. Rare earth ions, with their unique electronic configurations and optical properties, are pivotal in DC research related to solar cells. This review discusses the principles of DC technology and the synthesis of DC materials, emphasizing the application of rare earth-based DC materials in enhancing the efficiency and stability of various types of solar cells and their role in modifying the solar spectrum.

The widely used ZnO electron transport layer in inverted nonfullerene organic solar cells (nf-OSCs) offers advantages such as excellent electron mobility and optical transparency. However, challenges arise from surface defects in solution-processed ZnO, where oxygen-containing defects can penetrate the photoactive layer, leading to photocatalytic reactions with nonfullerene acceptors under UV light, thereby compromising device stability. Another challenge is that most recent high-efficiency nf-OSCs employ conventional structures, while inverted structures exhibit comparatively lower performance. To develop stable and high-performance inverted nf-OSCs, interface modification is essential to mitigate photocatalytic issues and enhance the relatively lower power conversion efficiency (PCE). To overcome these limitations, we introduce bathophenanthroline (BPhen) doped with Cs₂CO₃. The BPhen:Cs₂CO₃ layer creates suitable energy levels, enhancing electron transport and reducing charge recombination. This approach significantly improves current density and fill factor, resulting in a notable enhancement in the PCE of pristine ZnO devices from 15.54% to 17.09% in PM6:Y6 inverted nf-OSCs. Furthermore, ZnO/BPhen:Cs₂CO₃ devices exhibit excellent stability, retaining ~83% of their initial efficiency even after 1000 h without encapsulation, showcasing superior stability compared to pristine ZnO-based devices.

In the quest for advancing photovoltaic efficiency, the adoption of multijunction solar cell architectures has emerged as a promising approach. Perovskite/silicon double-junction solar cells have already achieved efficiencies surpassing 33%, exceeding the theoretical efficiency limit for single-junction devices. To enhance efficiency even further, exploring perovskite/perovskite/silicon (PPS) triple-junction solar cells seems a logical next step, as they offer the potential to further reduce thermalization losses and achieve even higher efficiencies. This study delves into the potential of various configurations of PPS modules, exploring different subcell interconnections. Initially, we present an optoelectrical model to simulate the performance of these devices, incorporating both luminescence coupling and cell-to-module losses. This enables us to optimize the bandgap energy of the top and middle perovskite subcells under both standard test conditions (STC) and outdoor conditions. Our analysis reveals that the addition of a perovskite subcell can improve the STC efficiency up to 9%–13%. This gain in STC performance also translates into a similar gain in energy yield, meaning that triple-junction devices produce 8%–14% more electricity than their double-junction reference devices.

The rising demand for sustainable low-power devices has driven interest in indoor photovoltaic (IPV) technologies for Internet of Things (IoT) applications. Composed of earth-abundant and non-toxic elements, Kesterite-based Cu₂ZnSnS₄ (CZTS) solar cells are highly attractive for IPV. This study systematically investigates the effects of sodium (Na), lithium (Li), and Na–Li co-doping on solution-processed CZTS devices. A comprehensive analysis reveals that Na-doping substantially improves crystallinity and grain morphology, significantly boosting efficiency, whereas Li alone has minimal impact. Notably, Na–Li co-doping achieves a 10.1% efficiency under AM 1.5G illumination, outperforming both the reference and singly doped devices. The co-doping synergy arises from Na-induced grain growth and Li-induced defect passivation and carrier concentration regulation. These devices exhibit high adaptability under 20 different indoor lighting conditions representative of real-world environments, achieving up to 15.1% power conversion efficiency under 3000 K illumination at 2.93 mW cm⁻²;—the highest reported indoor efficiency for CZTS cells. Their stable open-circuit voltage, high fill factor, and consistent efficiency across various color temperatures and intensities underline their suitability for IPV applications. Future work should focus on improving bandgap alignment with indoor light spectra to further enhance the efficiency of this eco-friendly technology for IoT energy solutions.

To commercialize perovskite solar cells (PSCs), it is crucial to develop cost-effective, dopant-free hole transport layers (HTLs) that can be processed at low temperatures. Herein, a dopant-free small molecular material 4,4′,4′-Tris[2-naphthyl(phenyl)amino]triphenylamine (2TNATA) was utilized in inverted PSCs as a HTL. The position of the highest occupied molecular orbital energy of 2TNATA is properly aligned with the perovskite valence band maximum. Moreover, 2TNATA can be processed at lower temperatures and shows excellent thermal stability. The lead (Pb) perovskite on 2TNATA exhibited superior crystallinity and morphology compared to the perovskite on poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA). Furthermore, the carrier kinetics in 2TNATA-based PSCs was superior to PTAA and PEDOT:PSS-based PSCs. Consequently, an outstanding power conversion efficiency (PCE) of 20.58% was observed from the 2TNATA HTL-based 0.09 cm² PSCs, while PTAA and PEDOT:PSS HTLs-based 0.09 cm² PSCs showed PCE of 19.36% and 14.35%, respectively. Moreover, the 2TNATA HTL-based 1.0 cm² PSCs demonstrated an impressive PCE of 20.04%. The results indicate that 2TNATA might be a promising HTL for the inexpensive and efficient inverted PSCs.