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Extracting hot‐carriers before they relax back to the band edge will reduce thermal dissipation above the bandgap, which is one of the primary sources of efficiency loss in perovskite solar cells (PSCs). It requires slow cooling of hot‐carriers together with the efficient extraction of hot‐carriers. Here, a novel interface engineering is demonstrated by embedding radical‐containing nanographene (r‐NG●) between perovskite and poly[bis(4‐phenyl)(2,4‐dimethoxyphenyl)‐amine] (PTOAA) to harvest this excess energy. This strategy accelerates the extraction rate of the hot‐hole (3 times that of control at 400 K) by augmenting the relaxation channel, which is related to the "quasi‐SOMO" energy state of r‐NG●. Nonadiabatic molecular dynamics calculation further revealed that radical character promotes the rotation of the cation in perovskite, which contributes to generating strong nonadiabatic couplings and multiple phonon modes. In addition, the band bending effect of buried perovskite and improved conductivity of PTOAA also facilitate exciton dissociation and hole collection efficiency (97.5%). Consequently, the resultant r‐NG● decorated PSCs delivered an impressive efficiency of 24.20%, along with better thermal and humidity stability. Moreover, it can maintain 93% of its initial efficiency after 300 hours of illumination. [ABSTRACT FROM AUTHOR]

Cs2AgPdBr5 is a new type of double perovskite with one-dimensional electronic dimensionality, which is expected to be a promising candidate of photovoltaic materials. Considering that defects usually exist in real materials, in this study, we investigate the intrinsic defect properties of Cs2AgPdBr5 from first principles. First, the phase diagram of Cs2AgPdBr5 is calculated. It turns out that its thermodynamic stable region is small, suggesting that the growth conditions should be carefully controlled to obtain high-quality samples. By systematically investigating the Fermi-level pinning behavior, we find that p-type Cs2AgPdBr5 can be obtained at an Ag-poor condition. At the same time, Pd 2+i and Pd 1+Ag are the only two deep-level recombination centers at 300 K. Therefore, if possible, the amount of palladium should be relatively small in the synthesis process. Our study provides guidance to obtain high-performance Cs2AgPdBr5 materials for photovoltaic applications. [ABSTRACT FROM AUTHOR]

The vehicle active suspension has been widely used as it could effectively improve the vehicle ride comfort. To solve the issues of actuator uncertainty and time delay existing in the active suspension system, a multi-objective non-fragile H ∞ control algorithm is proposed in this work. First, to effectively describe the vehicle suspension dynamics, a quarter-car suspension model is constructed first in this study. Second, aiming at improving the ride quality and guarantee the hard constraints of the suspension system, a multi-objective H 2/ H∞ performance index is proposed. Subsequently, the issues of external disturbances, actuator uncertainty and delay are considered in the design process of the suspension controller. Then, a multi-objective non-fragile control algorithm is proposed based on an effective Lyapunov functional. The control gain can be obtained by solving a convex optimization problem in terms of linear matrix inequalities. Finally, numerical simulations are implemented on MATLAB/Simulink platform to show the robustness and superiority of the proposed controller. Experiments are implemented on a quarter-car test rig to validate the practical performance of the designed controller. [ABSTRACT FROM AUTHOR]

Infiltration of excessive antibiotics into aquatic ecosystems plays a significant role in antibiotic resistance, a major global health challenge. It is therefore critical to develop effective technologies for their removal. Herein, defect-rich Bi 2 WO 6 nanoparticles are solvothermally prepared via epitaxial growth on pristine Bi 2 WO 6 seed nanocrystals, and the efficiency of the photocatalytic degradation of ciprofloxacin, a common antibiotic, is found to increase markedly from 62.51% to 98.27% under visible photoirradiation for 60 min. This is due to the formation of a large number of structural defects, where the synergistic interactions between grain boundaries and adjacent dislocations and oxygen vacancies lead to an improved separation and migration efficiency of photogenerated carriers and facilitate the adsorption and degradation of ciprofloxacin, as confirmed in experimental and theoretical studies. Results from this work demonstrate the unique potential of defect engineering for enhanced photocatalytic performance, a critical step in removing antibiotic contaminants in aquatic ecosystems., (© 2024 Wiley‐VCH GmbH.)

A recent experimental approach introduces sp 3 defects into single-walled carbon nanotubes (SWNTs) through controlled functionalization with guanine, resulting in a decrease in charge carrier lifetime. However, the physical mechanism behind this phenomenon remains unclear. We employ nonadiabatic molecular dynamics to systematically model the nonradiative recombination process of electron-hole pairs in SWNTs with sp 3 defects generated by a guanine molecule. We demonstrate that the introduction of sp 3 defects creates an overlapping channel between the highest occupied (HOMO) and lowest unoccupied molecular orbital (LUMO), significantly enhancing the nonadiabatic (NA) coupling and leading to a 4.7-fold acceleration in charge carrier recombination compared to defect-free SWNTs. The charge carrier recombination slows significantly at a lower temperature (50 K) due to the weakening of the NA coupling. Our results rationalize the accelerated recombination of charge carriers in SWNTs with sp 3 defects in experiments and contribute to a deeper understanding of the carrier dynamics in SWNTs.