RESUMEN
Over the past decade, the power conversion efficiency (PCE) of perovskite solar cells (PSCs) has experienced a remarkable ascent, soaring from 3.8% in 2009 to a remarkable record of 26.1% in 2023. Many recent approaches for improving PSC performance employ nanophotonic technologies, from light harvesting and thermal management to the manipulation of charge carrier dynamics. Plasmonic nanoparticles and arrayed dielectric nanostructures have been applied to tailor the light absorption, scattering, and conversion, as well as the heat dissipation within PSCs to improve their PCE and operational stability. In this review, it is begin with a concise introduction to define the realm of nanophotonics by focusing on the nanoscale interactions between light and surface plasmons or dielectric photonic structures. Prevailing strategies that utilize resonance-enhanced light-matter interactions for boosting the PCE and stability of PSCs from light trapping, carrier transportation, and thermal management perspectives are then elaborated, and the resultant practical applications, such as semitransparent photovoltaics, colored PSCs, and smart perovskite windows are discussed. Finally, the state-of-the-art nanophotonic paradigms in PSCs are reviewed, and the benefits of these approaches in improving the aesthetic effects and energy-saving character of PSC-integrated buildings are highlighted.
RESUMEN
Wide-bandgap (WBG) perovskites have attracted considerable attention due to their adjustable bandgap properties, making them ideal candidates for top subcells in tandem solar cells (TSCs). However, WBG perovskites often face challenges such as inhomogeneous crystallization and severe nonradiative recombination loss, leading to high open-circuit voltage (VOC ) deficits and poor stability. To address these issues, a multifunctional phenylethylammonium acetate (PEAAc) additive that enhances uniform halide phase distribution and reduces defect density in perovskite films by regulating the mixed-halide crystallization rate, is introduced. This approach successfully develops efficient WBG perovskite solar cells (PSCs) with reduced VOC loss and enhanced stability. By applying this universal strategy to the FAMACsPb(I1- x Brx )3 system with a range of bandgaps of 1.73, 1.79, 1.85, and 1.92 eV, power conversion efficiencies (PCE) of 21.3%, 19.5%, 18.1%, and 16.2%, respectively, are attained. These results represent some of the highest PCEs reported for the corresponding bandgaps. Furthermore, integrating WBG perovskite with organic photovoltaics, an impressive PCE of over 24% for two-terminal perovskite/organic TSCs, with a record VOC of ≈ 2.2 V is achieved. This work establishes a foundation for addressing phase separation and inhomogeneous crystallization in Br-rich perovskite components, paving the way for the development of high-performance WBG PSCs and TSCs.
RESUMEN
Organic photovoltaics (OPVs) have achieved great progress in recent years due to delicately designed non-fullerene acceptors (NFAs). Compared with tailoring of the aromatic heterocycles on the NFA backbone, the incorporation of conjugated side-groups is a cost-effective way to improve the photoelectrical properties of NFAs. However, the modifications of side-groups also need to consider their effects on device stability since the molecular planarity changes induced by side-groups are related to the NFA aggregation and the evolution of the blend morphology under stresses. Herein, a new class of NFAs with local-isomerized conjugated side-groups are developed and the impact of local isomerization on their geometries and device performance/stability are systematically investigated. The device based on one of the isomers with balanced side- and terminal-group torsion angles can deliver an impressive power conversion efficiency (PCE) of 18.5%, with a low energy loss (0.528 V) and an excellent photo- and thermal stability. A similar approach can also be applied to another polymer donor to achieve an even higher PCE of 18.8%, which is among the highest efficiencies obtained for binary OPVs. This work demonstrates the effectiveness of applying local isomerization to fine-tune the side-group steric effect and non-covalent interactions between side-group and backbone, therefore improving both photovoltaic performance and stability of fused ring NFA-based OPVs.
RESUMEN
Perovskite solar cells (PSCs) own rapidly increasing power conversion efficiencies (PCEs), but their concentrated counterparts (i.e., PCSCs) show a much lower performance. A deeper understanding of PCSCs relies on a thorough study of the intensive energy losses of the device along with increasing the illumination intensity. Taking the low band gap Sn-Pb PCSC as an example, we realize a device-level optoelectronic simulation to thoroughly disclose the internal photovoltaic physics and mechanisms by addressing the fundamental electromagnetic and carrier-transport processes within PCSCs under various concentration conditions. We find that the primary factor limiting the performance improvement of PCSCs is the significantly increased bulk recombination under the increased light concentration, which is attributed mostly to the inferior transport/collection ability of holes determined by the hole transport layer (HTL). We perform further electrical manipulation on the perovskite layer and the HTL so that the carrier-transport capability is significantly improved. Under the optoelectronic design, we fabricate low band gap PCSCs, which exhibit particularly high PCEs of up to 22.36% at 4.17 sun.
RESUMEN
Color-rendering manipulation of solar cells is drawing increasing interest, since the integration of color displaying can promote various advanced applications. However, the dual functionality of high-performance operation and easy processing remain a challenge. Here we propose a colorful perovskite solar cell (PSC) based on purely planar layers. The photonic crystal (PC), which does not interfere with the PSC processing, enables the display of high-purity colors and maintaining the number of PC layers at 4-6. The fabricated PSC with a four-layer PC successfully displays red-green-blue (RGB) colors, with the power-conversion efficiency of 10.94%, 11.01%, and 13.70%, respectively. Further study indicates that by employing a six-layer PC the PSC can obtain excellent color-displaying effect with the color gamut up to 81.8% of the standard RGB. It also shows that the design has a good tolerance to the deviation of layer thickness.
RESUMEN
Organic-inorganic heterojunction perovskite solar cell (PSC) is promising for low-cost and high-performance photovoltaics. To further promote the performance of PSCs, understanding and controlling the underneath photoconversion mechanisms are highly necessary. Here, we present a comprehensive opto-electro-thermal (OET) study on the heterojunction PSCs by quantitatively addressing the coupled optical, carrier transport, and thermodynamic behaviors within the device. With achieving a good agreement with the experiment, we theoretically explore the thermodynamic mechanisms involving the energy conversions and focus especially on the origins of the various energy losses in PSCs. We summarize six categories of microscopic heat conversion processes in the heterojunction PSC, where the Joule and Peltier heats can be defined as the intrinsic losses in PSCs. Moreover, we also discuss the possible manipulation methods to decrease the energy losses, for example, by tailoring the doping concentration and energy-level alignment. An exemplified OET optimization is also presented, which predicts that the PCE of the fabricated PSC can be enhanced from 21.37% to 23.84%.
RESUMEN
Passive radiative cooling technology has attracted extensive attention as it addresses the potential applications in effectively cooling photovoltaics and related systems. Here, we performed comprehensive multidimensional and multiphysical opto-electro-thermal (OET) modeling, which was used to design a silicon-based radiative cooling system for a solar cell (SC). Our study simultaneously takes into account the coupled effects of the radiative cooling characteristics, carrier thermodynamics, and electrodynamic behaviors of SCs in the spatial and frequency domains. Based on a comprehensive photonic design, we presented a radiative cooler with near-ideal spectral selectivity from the sunlight to the infrared band. The fundamental OET physical mechanisms and the effect of temperature on the performance of SCs were explored. A comparable study on the performance parameters of the SCs with and without a radiative cooler was formulated, which revealed that the SC temperature can be reduced by over 10 °C and the absolute power conversion efficiency (PCE) can be increased by 0.45% after employing a photonic radiative cooler. Our OET study provides a ready method to explore the comprehensive OET physics in photovoltaic systems.
RESUMEN
Colored solar cells (SCs) are highly useful for applications in esthetic building-integrated photovoltaics (BIPVs). However, the theoretical designs mostly focus on the color quality with rarely addressing the optoelectronic responses. Here, considering both color display and complete electrical evaluation, we report a color-controlled a-Si:H SC in purely planar configuration, which simultaneously exhibits the desired high-purity color and sustains a relatively high power conversion efficiency. The high-performance color display is realized by thin-film photonic designs with incorporating distributed Bragg reflector and anti-reflection coating layers. Moreover, a comprehensive optoelectronic simulation addressing both the electromagnetic and internal semiconductor physics has been realized, which shows that the power conversion efficiencies of the designed red-green-blue (RGB) SCs can be 4.88%, 5.58%, and 6.54%, respectively. The physical principles of optimizing the colorful SCs with the tunable hue, high saturation, and brightness are explained, and we take the logo of "Soochow University" as an example to demonstrate the wide-angle pattern display by the SCs. The study paves the way of realizing the colored SCs targeting esthetic BIPV applications.
