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Recently, carbon-based perovskite solar cells have attracted wide attention in academia and industry because of their simple preparation process, low cost, and adaptability to roll-to-roll industrial production. The combination of ternary perovskite composition and carbon electrode configuration is expected to meet the requirements of device performance and stability. However, low grain size, and high density of grain boundary and surface defect states result in serious non-radiative recombination, which is one of the main gaps between the carbon-based perovskite solar cells and metal-electrode-based devices. Based on the consideration of crystal tuning and defect passivation of ternary CsFAMA thin films, the additive molecule 5-(Difluoromethoxy)-2-mercapto-1H-benzimidazole (DMB) with multifunctional groups were introduced into the film. XRD show that the (100) and (200) crystal plane orientation growth directed by the DMB additive lead to the formation of the micro-sized perovskite. XPS suggests that DMB not only modulates the crystallization of the films but also exists at the grain boundaries, and realizes the passivation of undercoordinated Pb2+ defects and inhibits the generation of Pb0. The defect state density is significantly reduced, and the carrier lifetime is greatly improved. The possible mechanism for perovskite crystal growth as well as defect passivation based on Lewis acid-base coordination and hydrogen bond was also proposed. After the introduction of DMB, a power conversion efficiency of 14.40% was achieved, which was 13.4% higher than that of the control device. After nearly 1200 h of environmental stability test, the DMB modified device still retained 95% of the original efficiency. This work emphasizes the feasibility of simultaneously realizing the crystallization modulation and defect passivation of carbon-based perovskite solar cells using the additive with multifunctional groups, and provides a reference for the commercialization of carbon-based perovskite solar cells. [Display omitted] • Commercially available carbon was used instead of the noble metals. • Crystallization modulation and defect passivation are realized simultaneously. • The C-PSC based on DMB additive show 13.4% increase in PCE. • The C-PSC based on DMB additive possess exceptional long-term stability. [ABSTRACT FROM AUTHOR]

Because of its exceptional photoelectric qualities, exceptional stability, and plentiful element resources, the antimony selenide (Sb 2 Se 3) can be used as an absorber layer. The performance of solar cells needs to be further improved. Comprehending the various surface treatment conditions is instrumental in optimizing device performance. In this research, we pre-treated the fluorine-doped tin oxide (FTO) surface with ultraviolet ozone (UV/O 3) and investigated how the device (FTO/CdS (53 nm)/Sb 2 Se 3 (203 nm)/Spiro(120 nm)/Au(80 nm)) performance was affected by temperature of the substrate during the UV/O 3 treatment. It's interesting to note that the solar cells made with FTO after exposure to UV/O 3 have better interface quality and lower recombination losses, which significantly improves the Open circuit voltage (V OC) and Fill factor (FF). The result is an improvement in the device's Power Conversion Efficiency (PCE) from 7.13% to 8.14%. The work is aimed at developing an efficient strategy to improve the performance of Sb 2 Se 3 solar cells. [ABSTRACT FROM AUTHOR]

The limited exciton lifetime (τ, generally <1 ns) leads to short exciton diffusion length (LD) of organic semiconductors, which is the bottleneck issue impeding the further improvement of power conversion efficiencies (PCEs) for organic solar cells (OSCs). However, efficient strategies to prolong intrinsic τ are rare and vague. Herein, we propose a facile method to efficiently reduce vibrational frequency of molecular skeleton and suppress exciton‐vibration coupling to decrease non‐radiative decay rate and thus prolong τ via deuterating nonfullerene acceptors. The τ remarkably increases from 0.90 ns (non‐deuterated L8‐BO) to 1.35 ns (deuterated L8‐BO‐D), which is the record for organic photovoltaic materials. Besides, the inhibited molecular vibration improves molecular planarity of L8‐BO‐D for enhanced exciton diffusion coefficient. Consequently, the LD increases from 7.9 nm (L8‐BO) to 10.7 nm (L8‐BO‐D). The prolonged LD of L8‐BO‐D enables PM6 : L8‐BO‐D‐based bulk heterojunction OSCs to acquire higher PCEs of 18.5 % with more efficient exciton dissociation and weaker charge carrier recombination than PM6 : L8‐BO‐based counterparts. Moreover, benefiting from the prolonged LD, D18/L8‐BO‐D‐based pseudo‐planar heterojunction OSCs achieve an impressive PCE of 19.3 %, which is among the highest values. This work provides an efficient strategy to increase the τ and thus LD of organic semiconductors, boosting PCEs of OSCs. [ABSTRACT FROM AUTHOR]

The limited exciton lifetime (τ, generally <1 ns) leads to short exciton diffusion length (LD) of organic semiconductors, which is the bottleneck issue impeding the further improvement of power conversion efficiencies (PCEs) for organic solar cells (OSCs). However, efficient strategies to prolong intrinsic τ are rare and vague. Herein, we propose a facile method to efficiently reduce vibrational frequency of molecular skeleton and suppress exciton‐vibration coupling to decrease non‐radiative decay rate and thus prolong τ via deuterating nonfullerene acceptors. The τ remarkably increases from 0.90 ns (non‐deuterated L8‐BO) to 1.35 ns (deuterated L8‐BO‐D), which is the record for organic photovoltaic materials. Besides, the inhibited molecular vibration improves molecular planarity of L8‐BO‐D for enhanced exciton diffusion coefficient. Consequently, the LD increases from 7.9 nm (L8‐BO) to 10.7 nm (L8‐BO‐D). The prolonged LD of L8‐BO‐D enables PM6 : L8‐BO‐D‐based bulk heterojunction OSCs to acquire higher PCEs of 18.5 % with more efficient exciton dissociation and weaker charge carrier recombination than PM6 : L8‐BO‐based counterparts. Moreover, benefiting from the prolonged LD, D18/L8‐BO‐D‐based pseudo‐planar heterojunction OSCs achieve an impressive PCE of 19.3 %, which is among the highest values. This work provides an efficient strategy to increase the τ and thus LD of organic semiconductors, boosting PCEs of OSCs. [ABSTRACT FROM AUTHOR]

• A shape editing approach of single-DoF thick-panel deployable structures is proposed. • The mobility of thick-panel deployable structures is analyzed using screw theory. • The design of novel solar panels and space exposing platforms is further explored. Thick-panel deployable structures have great engineering prospects in aerospace large-scale structures. However, achieving any desired shape of the deployable structure without seams, compact folding, and single-degree-of-freedom (single-DoF) deployment is a significant challenge for aerospace engineering applications. In this study, we propose an approach to edit the shape of kirigami-inspired thick-panel structures that enable single-DoF flat deploying and compact folding. First, based on two-vertex six-crease kirigami-inspired TPUs, modular assembly of single-DoF thick-panel deployable structures are achieved. Second, the single-DoF characteristics of resulting thick-panel structures are verified using screw theory and topology. Third, panel cutting and merging of the assembled thick-panel structures is performed to ensure the topological closed-loop characteristics in the desired shape of the structures while maintaining its single-DoF characteristics. In addition, their potential engineering applications in space solar arrays and exposing platforms are further explored. The proposed method provides some references for the design of future thick-panel deployable structures. [ABSTRACT FROM AUTHOR]

• A configuration of twofold spectrum split is proposed for high exergy efficiency in PV/T systems. • A coupling model of PV/T system is constructed and validated by our experiments. • Tailoring the spectral selectivity and deep temperature decoupling is enabled by our configuration. • Total energy and exergy efficiencies reach 0.829 and 0.276 for solar concentration of 30. Photovoltaic/thermal (PV/T) systems are improved from PV systems to harvest both electrical and thermal energy from the solar radiation, as well as cooling the PV cells. While the previous configurations with liquid-absorptive filters have partly solved the temperature coupling of PV cells and heat collector, the unsatisfactory spectral selectivity and inevitably interlayer heat transfer remain restrict the improvement of total exergy efficiency in PV/T systems. In this study, a twofold spectrum split configuration with both Therminol VP-1/Ag nanofluid and pure water is proposed. The complementary optical properties and free flow rate controls open a window to tailoring the spectral selectivity and deep temperature decoupling. A coupling model is constructed to describe the system, which is well validated by our simplified PV/T experiment and literature. Results show that the nanofluid absorbs the shorter unsuited radiation, and water captures the longer, leading to a high spectral match parameter (0.71) and low heat generation parameter (0.26) when for nanofluid thickness of 1 mm, water thickness of 10 mm and Ag nanoparticle volume fraction of 0.01 %. Total exergy efficiency increases with solar concentration, and the highest value of 0.276 is reached for solar concentration of 30 when flow rates of nanofluid and water are 0.032 and 0.029, with an accompanying total energy efficiency of 0.829. As a comparison, two previous PV/T systems have highest total exergy efficiencies even lower than 0.25. Temperature distributions revealed that the deep temperature decoupling in the proposed PV/T system enables a high-temperature heat collection during the low-temperature work of PV cells, which is responsible for the improvement. Our study points out an approach to combine the advantages of two liquid filters, to achieve both good spectral selectivity and deep temperature decoupling. [ABSTRACT FROM AUTHOR]