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A polyethylenimine (PEI)-scaffolded and functionalized graphene aerogel, PEI-GO-AG, was prepared and utilized as a highly selective adsorbent for the extraction of thorium (Th) (IV) from three lanthanides (Ln) (III) elements. The three dimensional (3D)-porous structure of the adsorbent was established by the cross-linking effect of PEI via a one-step hydrothermal strategy and preserved by a freeze-drying treatment to avoid the collapse of the structure. The extractive efficiency of PEI-GO-AG displayed a sensitive dependence on the beginning mass ratio of PEI/graphene oxide (GO) in the hydrothermal step because of its significant influence on the hydrophilicity and the amounts of introduced binding sites of the adsorbent.. Besides, a density function theory (DFT)-based theoretical calculation was performed, confirming the higher stability of Th (IV)-PEI-GO-AG than that of Ln (III)-PEI-GO-AG. Ascribed to these contributions, the as-prepared adsorbent showed high selectivity towards Th (IV) among three Ln (III) elements. The separation factor (SF) values of Th (IV) to lanthanum (La) (III), europium (Eu) (III), and lutetium (Lu) (III) were SF Th/La = 114.41, SF Th/Eu = 52.75, and SF Th/Lu = 107.81, respectively. Graphical abstract Unlabelled Image • 1Dimensional-porous graphene oxide aerogel was established using polyethylenimine as the cross-linking and functionalizing agent. • The adsorbent possesses high selectivity arising from the dimensional-porous structure, the introduced binding sites, and the high hydrophilicity. • The adsorptive performance of the adsorbent showed a sensitively dependent relationship on the beginning mass ratio of polyethylenimine/graphene oxide. • A density functional theory simulation was performed, proving the adsorption complex of thorium possessed the lowest energy. [ABSTRACT FROM AUTHOR]

• Perfluorooctane sulfonamide can transform to perfluocarboxylic acids under sunlight. • Clay mineral can promote the transformation of perfluorooctane sulfonamide. • Water-montmorillonite interface can generate superoxide anion and hydroxyl radical. In this study, a new phototransformation pathway for perfluorooctane sulfonamide (FOSA) and underlying degradation mechanisms are described. Phototransformation of FOSA in a natural clay mineral (montmorillonite) suspension was compared to that in an aqueous solution. Results showed that the presence of montmorillonite can significantly promote the transformation of FOSA to perfluocarboxylic acids (increasing rate). The phototransformation reaction was found to be initiated by the activation of adsorbed oxygen molecules on the surface of montmorillonite, which generate superoxide anion and hydroxyl radicals. Hydroxyl radicals can then attack FOSA adsorbed onto the surface of montmorillonite, promoting the transformation process. In this reaction, clay minerals played a dual role: providing hydroxyl radicals and concentrating FOSA on their surfaces. This helped to promote the contact and reaction between FOSA and hydroxyl radicals. This study provides the first evidence that heterogeneous oxidation of FOSA at the surface of natural clay minerals may act as an important source of perfluocarboxylic acids (PFCAs), especially short chain PFCAs (i.e. trifluoroacetic acid, TFA). [ABSTRACT FROM AUTHOR]

The substrates formed by the self-assembly method of metal nanoparticles are widely used in the molecular detection due to their high uniformity and good SERS properties. In this paper, we used the sliver nanorods as the building block for the first time to produce close-packed vertical arrays via evaporation-induced method. The results showed that the optimized substrates have good performance with excellent enhancement factor (4.47 × 105) and high reproducibility. By the time, we explore the relationship between the length of silver nanorods and the intensity of 4-mercaptobenzoic acid (4-MBA). The optimal SERS performance depended on longest silver nanorod length. In addition, the optimized vertical silver nanorod substrates exhibit 3 times than the optimized six-layer three-dimensional horizontal ones. Furthermore, the optimized substrate was able to directly detect malachite green (MG) down to 10−9 M. At the same time, the on-site detection of the thiram in the peel of apple is as low as 0.1 ng cm−2. The experimental results clearly show that our substrates have great potential for environmental monitoring, food safety and security application. [ABSTRACT FROM AUTHOR]

[Display omitted] • New ionic TADF emitters based on O/S-fused arylphosphonium electron acceptors. • Simultaneously attaining high PLQYs, short exciton lifetimes, and high RISC rates. • Realizing solution-processed OLEDs with high EQEs and small efficiency roll-offs. Ionic thermally activated delayed fluorescence (iTADF) materials are newly emerging as promising candidates for constructing solution-processed electroluminescence devices. Developing iTADF materials with high emission efficiency, short exciton lifetime, and fast reverse intersystem crossing (RISC) is crucial for achieving stable and efficient organic light-emitting diodes (OLEDs), but it remains challenging. Here we report two high-performance iTADF emitters, namely DMAC-TPPO[BF 4 ] and DMAC-TPPS[BF 4 ], which consist of a conventional acridine as the electron-donor and newly developed oxygen/sulfur-fused arylphosphonium derivatives as the electron-acceptor. DMAC-TPPO[BF 4 ] and DMAC-TPPS[BF 4 ] exhibit high photoluminescence quantum yields of 77 % and 83 %, coupled with short exciton lifetimes of 1.2 and 1.1 μs, and RISC rate constants reaching up to 2.60 × 106 and 2.73 × 106 s−1, respectively. Theoretical and experimental investigations demonstrate that the imbedding of bridging heteroatoms into the phosphonium cation is pivotal for enhancing emission efficiency through molecular skeleton rigidification, as well as for accelerating the RISC process by capitalizing on the non-metal heavy-atom effect. Eventually, solution-processed OLEDs utilizing DMAC-TPPS[BF 4 ] realize a peak external quantum efficiency (EQE) of 17.8 % and show a minor efficiency roll-off of 7.3 % (EQE = 16.5 %) even at a practical high luminance of 1000 cd/m2. [ABSTRACT FROM AUTHOR]

• Highly efficient ionic TADF emitters with fast RISC and short exciton lifetimes. • The effects of anions on the PL and EL properties are systematically studied. • Realizing high-performance solution-processed iTADF-OLED via anion regulations. Ionic thermally activated delayed fluorescence (iTADF) materials have rarely been reported and applied in organic light emitting diodes (OLEDs) owing to their poor sublimability, photoluminescence (PL) and electroluminescence (EL) performance. It is appealing and challenging to develop iTADF emitters for high-performance OLEDs based on a deep understanding of their structure–property relationship. In this work, we report three new iTADF materials, DMAC-TPP[Br], DMAC-TPP[BF 4 ] and DMAC-TPP[BArF 24 ], which have the same phosphonium-cation-based chromophore and different counter anions. These materials show excellent PL properties, e.g., high photoluminescence quantum yields (PLQYs), short exciton lifetimes and fast reverse intersystem crossing (RISC). The comparative studies reveal that the photophysical properties of these iTADF materials are slightly affected by the anions via molecular configuration, intra-/inter-molecular interactions and molecular stacking. More importantly, we find that the anions play a key role in determining the EL performance of the iTADF emitters. The change of anions can lead to 3-fold increased external quantum efficiency (EQE), over 21-fold increased luminance and significantly suppressed efficiency roll-offs for the iTADF-OLEDs. The solution-processed OLED based on DMAC-TPP[BF 4 ] achieved a EQE of 15.1 % with small efficiency roll-offs of only 0.7 % and 10.6 % at luminance of 100 cd/m2 and 1000 cd/m2, and a maximum luminance of 10400 cd/m2. The significant difference in EL performance is ascribed to the different charge recombination governed by the migration and hole-trapping ability of anions under an electric field. These results motivate the further development of high-performance iTADF materials for EL applications by anion engineering. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) emitters in the long wavelength region usually suffer from severe nonradiative decay according to the energy-gap law, and show relatively large energy split (ΔE ST) between the lowest singlet and triplet excited states which compromise efficient up-conversion. Here, we report three orange and red TADF emitters comprising 5, 10-disubstituted phenazine electron-donor and quinoxaline-derived electron-acceptors, which show excellent TADF properties and yield efficient organic light-emitting diodes (OLEDs). These symmetrical acceptor-donor-acceptor (A-D-A) type and rodlike molecules concurrently exhibit high photoluminescence quantum yields up to 85% and fast reverse intersystem crossing. Experimental and theoretical studies reveal that these excellent photophysical properties are attributed the synergistic effect of structural rigidity, steric hindrance and strength of the donor and acceptor units. Doped OLEDs based on these emitters achieved high maximum external electroluminescence quantum efficiencies up to 19.9%, and maximum luminance surpassing 31240 cd/m2. [Display omitted] • Highly efficient orange to red TADF emitters with high PLQYs (up to 85%) and short TADF lifetimes. • Tiny S 1 -T 1 energy splits and fast spin-flip due to rational molecular design and excited-state regulation. • High-performance OLED with EQE nearly 20%. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) materials with through-space charge transfer (TSCT) have recently attracted extensive attention. However, how to rationally design high-performance TSCT-TADF emitters with small ΔE ST , high photoluminescence quantum yields (PLQYs) and high stability remains challenging. Herein, two triptycene-derived TADF molecules bearing ortho-donor (D)-acceptor (A) conformations are designed and characterized. These emitters exhibit unique V-shaped face-to-face D-A alignments with significant intramolecular D-A interactions, which mediate TSCT between the D and A moieties in addition to the through-bond charge transfer (TBCT) and facilitate realizing small ΔE ST and high efficiencies. Meanwhile, the rigid 3D triptycene scaffold endows the emitters with excellent thermal stability and high film-formation quality. These TADF emitters exhibit small ΔE ST of 6.7 and 10.8 meV and high photoluminescence quantum yields of 0.80 and 0.40 in doped films, respectively. The doped OLEDs employing these emitters achieve high external quantum efficiencies up to 20.5%. [Display omitted] • 3D triptycene scaffold based TADF emitters with photoluminescent efficiency up to 80%. • V-shaped face-to-face D-A conformation for constructing through-space charge transfer (TSCT) pathway. • High performance OLED with EQE beyond 20%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lock/unlock strategy proposed to manipulate excited states and photophysical properties of TADF materials. • Efficient TADF emitters with high PLQYs (up to 0.91), short TADF lifetimes and excellent stability and film-quality. • High-performance OLED with EQE beyond 25%. Thermally activated delayed fluorescent (TADF) materials have drawn widespread attentions due to their great potential for practical applications in organic light-emitting diodes (OLEDs). Deep understanding of the structure-excited state-photophysical property relationships is a key to rationally design TADF emitters. Herein, two new TADF molecules, TBP-DPXZ and TBQ-DPXZ, which consist of locked (triptycene-fused dibenzophenazine) and unlocked (triptycene-fused 2, 3-diphenylquinoxaline) electron-acceptors respectively and phenoxazine electron donors are reported. The comparative study reveals that the lock/unlock strategy could substantially manipulate the lowest locally excited (LE) and charge transfer (CT) states of these emitters via changing the acceptor strength, structural rigidity, and conjugation length, and in turn lead to significantly different photoluminescence (PL) and electroluminescence (EL) performance. It is notable that the unlocked molecule TBQ-DPXZ emits efficient green fluorescence with photoluminescence quantum yield of 91% and TADF lifetime of 3.6 μs in doped film. The doped OLED based on TBQ-DPXZ achieves an external quantum efficiency (EQE) of 25.1%, a current efficiency (CE) of 79.7 cd/ A, a power efficiency (PE) of 80.0 lm/W, and a maximum luminance of 18400 cd/m2, which are better than those of the TBP-DPXZ-based device and are among the best results reported so far for green TADF-OLEDs. [ABSTRACT FROM AUTHOR]

Designing all-inorganic double perovskites through element mixing is a promising strategy to enhance their optoelectronic performance and structural stability. The complex interplay between multilevel structures and optoelectronic properties in element-mixed double perovskites necessitates further in-depth theoretical exploration. In this study, we employ screening strategies and multiscale simulations combining first-principles methods and device-scale continuum models to identify two novel element-mixed compounds, Rb 2 AgInCl 3 I 3 and Cs 2 AgInCl 3 I 3 , as promising candidates for photovoltaic applications. These compounds exhibit favorable structural factors and suitable direct band gaps. Theoretical investigations using first-principles methods with the HSE06 functional reveal direct band gaps of 0.98 and 1.26 eV for Rb 2 AgInCl 3 I 3 and Cs 2 AgInCl 3 I 3 , respectively, with corresponding optical absorption coefficients exceeding 10 5 cm -1 in the visible light range. Cs 2 AgInCl 3 I 3 features high charge mobilities of approximately 20 cm 2 ·V -1 ·s -1 and a notable single-junction spectroscopic limited maximum efficiency (SLME) of 25.54%. Further analysis using the device-scale continuum model simulated the nonradiative recombination effects on power conversion efficiency, integrating quantum-mechanically calculated optoelectronic properties. These theoretical investigations, which bridge composition engineering with multiscale simulations, provide valuable insights into screening novel, lead-free, halogen - mixed double metal perovskite optoelectronic devices, highlighting their potential for high-performance solar energy applications.

Simultaneously achieving a high photoluminescence quantum yield (PLQY), ultrashort exciton lifetime, and suppressed concentration quenching in thermally activated delayed fluorescence (TADF) materials is desirable yet challenging. Here, a novel acceptor-donor-acceptor type TADF emitter, namely, 2BO-sQA, wherein two oxygen-bridged triarylboron (BO) acceptors are arranged with cofacial alignment and positioned nearly orthogonal to the rigid dispirofluorene-quinolinoacridine (sQA) donor is reported. This molecular design enables the compound to achieve highly efficient (PLQYs up to 99%) and short-lived (nanosecond-scale) blue TADF with effectively suppressed concentration quenching in films. Consequently, the doped organic light-emitting diodes (OLEDs) base on 2BO-sQA achieve exceptional electroluminescence performance across a broad range of doping concentrations, maintaining maximum external quantum efficiencies (EQEs) at over 30% for doping concentrations ranging from 10 to 70 wt%. Remarkably, the nondoped blue OLED achieves a record-high maximum EQE of 26.6% with a small efficiency roll-off of 14.0% at 1000 candelas per square meter. By using 2BO-sQA as the sensitizer for the multiresonance TADF emitter ν-DABNA, TADF-sensitized fluorescence OLEDs achieve high-efficiency deep-blue emission. These results demonstrate the feasibility of this molecular design in developing TADF emitters with high efficiency, ultrashort exciton lifetime, and minimal concentration quenching., (© 2024 Wiley‐VCH GmbH.)

Thermally activated delayed fluorescence (TADF) emitters based on the triptycene skeleton demonstrate exceptional performance, superior stability, and low efficiency roll-off. Understanding the interplay between the luminescent properties of triptycene-TADF molecules and their assembly environments, along with their excited-state characteristics, necessitates a comprehensive theoretical exploration. Herein, we predict the photophysical properties of triptycene-TADF molecules in a thin film environment using the quantum mechanics/molecular mechanics method and quantify their substantial dependency on the heavy atom effects and reorganization energies using the Marcus-Levich theory. Our calculated photophysical properties for two recently reported molecules closely align with experimental values. We design three novel triptycene-TADF molecules by incorporating chalcogen elements (O, S, and Se) to modify the acceptor units. These newly designed molecules exhibit reduced reorganization energies and enhanced reverse intersystem crossing (RISC) rates. The heavy atom effect amplifies spin-orbit coupling, thereby facilitating the RISC process, particularly at a remarkably high rate of ∼10 9 s -1 .

Recently, thermally activated delayed fluorescence (TADF) molecules with through-space charge transfer (TSCT) features have been widely applied in developing organic light-emitting diodes with high luminescence efficiencies. The performance of TSCT-TADF molecules depends highly on their molecular structures. Therefore, theoretical investigation plays a significant role in designing novel highly efficient TSCT-TADF molecules. Herein, we theoretically investigate two recently reported TSCT-TADF molecules, 1'-(2,12-di- t -butyl[1,4]benzoxaborinino[2,3,4- kl ]phenoxaborinin-7-yl)-10-phenyl-10 H -spiro[acridine-9,9'-fluorene] (AC-BO) and 1-(2,12-di- t -butyl[1,4]benzoxaborinino[2,3,4- kl ]phenoxaborinin-7-yl)-9',9'-dimethyl-9' H -spiro [fluorene-9,5'-quinolino[3,2,1- de ]acridine](QAC-BO). The calculated photophysical properties ( e.g. excited state energy levels and luminescence properties) for these two compounds are in good agreement with experimental data. Based on the systematic analysis of structure-performance relationships, we design three novel TSCT-TADF molecules with high molecular rigidity and evident TSCT features, i.e. , DQAC-DBO, DQAC-SBO, and DQAC-NBO. They exhibit deep-blue light emissions and fast reverse intersystem crossing rates ( K RISC s). Our calculations demonstrate that the nearly coplanar orientation of the donor and acceptor is critical to achieve remarkable K RISC s and fluorescence efficiencies in TSCT-TADF molecules.

Designing and synthesizing fullerene bisadducts with a higher-lying conduction band minimum is promising to further improve the device performance of tin-based perovskite solar cells (TPSCs). However, the commonly obtained fullerene bisadduct products are isomeric mixtures and require complicated separation. Moreover, the isomeric mixtures are prone to resulting in energy alignment disorders, interfacial charge loss, and limited device performance improvement. Herein, we synthesized single-isomer C 60 - and C 70 -based diethylmalonate functionalized bisadducts (C 60 BB and C 70 BB) by utilizing the steric-hindrance-assisted strategy and determined all molecular structures involved by single crystal diffraction. Meanwhile, we found that the different solvents used for processing the fullerene bisadducts can effectively regulate the molecular packing in their films. The dense and amorphous fullerene bisadduct films prepared by using anisole exhibited the highest electron mobility. Finally, C 60 BB- and C 70 BB-based TPSCs showed impressive efficiencies up to 14.51 and 14.28%, respectively. These devices also exhibited excellent long-term stability. This work highlights the importance of developing strategies to synthesize single-isomer fullerene bisadducts and regulate their molecular packing to improve TPSCs' performance.

Thermally activated delayed fluorescence (TADF) materials with both high photoluminescence quantum yield (PLQY) and fast reverse intersystem crossing (RISC) are strongly desired to realize efficient and stable organic light-emitting diodes (OLEDs). Control of excited-state dynamics via molecular design plays a central role in optimizing the PLQY and RISC rate of TADF materials but remains challenging. Here, 3 TADF emitters possessing similar molecular structures, similar high PLQYs (89.5% to 96.3%), and approximate energy levels of the lowest excited singlet states (S 1 ), but significantly different spin-flipping RISC rates (0.03 × 10 6 s -1 vs. 2.26 × 10 6 s -1 ) and exciton lifetime (297.1 to 332.8 μs vs. 6.0 μs) were systematically synthesized to deeply investigate the feasibility of spin-flip between charge-transfer excited states ( 3 CT- 1 CT) transition. Experimental and theoretical studies reveal that the small singlet-triplet energy gap together with low RISC reorganization energy between the 3 CT and 1 CT states could provide an efficient RISC through fast spin-flip 3 CT- 1 CT transition, without the participation of an intermediate locally excited state, which has previously been recognized as being necessary for realizing fast RISC. Finally, the OLED based on the champion TADF emitter achieves a maximum external quantum efficiency of 27.1%, a tiny efficiency roll-off of 4.1% at 1,000 cd/m 2 , and a high luminance of 28,150 cd/m 2 , which are markedly superior to those of the OLEDs employing the other 2 TADF emitters., (Copyright © 2023 Donghai Zhang et al.)

PFAS (per- and polyfluoroalkyl substances) are omnipresent in the environment and their transportation and transformation have attracted increased attention. Microplastics are another potential risk substances that can serve as a carrier for ubiquitous pollutants, thus affecting the presence of PFAS in the environment. In this study, the adsorption of perfluorooctane sulfonamide (FOSA) and perfluorooctanoic acid (PFOA) on four microplastics (PE, PVC, PS, and PTFE) and their effect on the photodegradation of FOSA were studied. The adsorption capacity of FOSA by PS was the highest, in similar, PS displayed the highest adsorption capacity in the presence of PFOA. Different effects of pH and salinity on the adsorption of FOSA and PFOA were observed among different microplastics indicating inconsistent interaction mechanisms. Furthermore, FOSA could be photodegraded, with PFOA as the main product, while the presence of microplastics had a negligible effect on the degradation of this contaminant. The results indicated that microplastics could act as PFAS concentrators. Moreover, their photochemical inertias make the pollutants enriched on microplastics more resistant to degradation., Competing Interests: Declaration of Competing Interest We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2022. Published by Elsevier B.V.)

Developing novel lead-free perovskite materials with suitable bandgaps and superior thermal stability is crucial to boost their applications in next-generation photovoltaic technologies. High throughput screening combined with the first principles method can accurately and effectively screen out promising perovskites. Herein, we select two lead-free all-inorganic halide double perovskite materials Cs 2 KMI 6 (M = Ga, In) from 1026 compounds with the criteria including appropriate structure factors, positive decomposition energies, and suitable direct bandgaps. We investigated the thermal and mechanical stability, geometric and electronic structures, photoelectric properties, and defect formation energies for both perovskites Cs 2 KMI 6 (M = Ga, In). They can exhibit excellent structural formability and stability through the analysis of structure factors, elastic constants, and stable chemical potential regions. In addition, we investigate the defect effects of Cs 2 KMI 6 (M = Ga, In) on the photovoltaic performance by evaluating the defect formation energies and transition energy levels. Based on the HSE06 functional, we calculated the energy band structures of these two compounds and demonstrate the direct bandgaps of 1.69 eV (HSE06) and 2.16 eV (HSE06) for Cs 2 KGaI 6 and Cs 2 KInI 6 , respectively. Moreover, we predicted excellent spectroscopic limited maximum efficiencies (SLMEs) of these two perovskites with high light absorption coefficients (around 10 5 cm -1 ), for instance, the SLME of Cs 2 KGaI 6 can reach as high as 28.39%.

Tin-based perovskite solar cells (TPSCs) are attracting intense research interest due to their excellent optoelectric properties and eco-friendly features. To further improve the device performance, developing new fullerene derivatives as electron transporter layers (ETLs) is highly demanded. Four well-defined regioisomers (trans-2, trans-3, trans-4, and e) of diethylmalonate-C 60 bisadduct (DCBA) are isolated and well characterized. The well-defined molecular structure enables us to investigate the real structure-dependent effects on photovoltaic performance. It is found that the chemical structures of the regioisomers not only affect their energy levels, but also lead to significant differences in their molecular packings and interfacial contacts. As a result, the devices with trans-2, trans-3, trans-4, and e as ETLs yield efficiencies of 11.69%, 14.58%, 12.59%, and 10.55%, respectively, which are higher than that of the as-prepared DCBA-based (10.28%) device. Notably, the trans-3-based device also demonstrates a certified efficiency of 14.30%, representing one of the best-performing TPSCs., (© 2023 Wiley-VCH GmbH.)

Recently, a family of [Fe 2 Co 2 ] molecular capsules that display tunable electron transfer-coupled spin transition (ETCST) behavior were reported via a smart approach through Schiff-base condensation of aldehyde-functionalized 2,2-bipyridines (bpy CHO ) and 1,7-heptanediamine (H 2 N(CH 2 ) 7 NH 2 ). Here, three more capsule complexes {[(Tp R )Fe(CN) 3 ] 2 [Co(bpy CN(CH 2 ) n NC bpy)] 2 [ClO 4 ] 2 }· n (solvent) (1, Tp R = Tp*, n = 5, sol = 8DMF; 2, Tp R = Tp Me , n = 9, sol = 5MeCN; and 3, Tp R = Tp*, n = 11, sol = 5MeCN), where Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate and Tp Me = hydridotris(3-methylpyrazol-1-yl)borate are reported, demonstrating a successful extension of such an approach with other alkyldiamines of different lengths. Combined X-ray crystallographic, infrared spectroscopic and magnetic studies reveal incomplete electron transfer with either changing temperature or upon light exposure.

Since the COVID-19 pandemic broke out in 2019, neuroticism has been proven a predictor of fear of COVID-19 infection. However, only few studies have been conducted on the factors affecting the relationship between neuroticism and this kind of fear. The present study is aimed at analyzing the role intolerance of uncertainty (IU) and sense of control (SOC) play in relation to neuroticism and the fear of COVID-19. We conducted a cross-sectional study in Guangdong and Guangxi provinces, China, and we collected complete datasets from 792 high school students. The main results can be described as follows: (a) individuals with high neuroticism tended to have higher intolerance of uncertainty (IU) and a lower sense of control (SOC); (b) IU and SOC played a mediating role between neuroticism and fear of COVID-19, and a serial mediation effect was found between these factors; (c) after controlling for both IU and SOC, the effect of neuroticism on fear was no longer significant. The results suggested a critical role of IU and sense of control in the causal relationship between neuroticism and fear., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhang, Fan, Meng and Zheng.)

It has been recognized that both the ligand fields and intermolecular interactions may greatly impact the electron-transfer-coupled spin transition (ETCST) events in switchable magnetic materials; however, the engineering of these factors within a given system is still challenging. In this article, we chose the 4,4'-substituent 2,2'-bipyridine derivatives as chelating ligands according to their increasing electron-donating strength and incremental potential for forming hydrogen bonds (bpy CHO,CH 3 (L1) < bpy CH 2 OH,CH 3 (L2) < bpy CH 2 OH,CH 2 OH (L3)), and prepared three new [Fe 2 Co 2 ] complexes, {[(Tp*)Fe(CN) 3 Co(L) 2 ] 2 [ClO 4 ] 2 }·Sol (1, L = L1, Sol = 4MeCN·2H 2 O; 2, L = L2, Sol = 3MeCN; 3, L = L3, Sol = 4MeOH; Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate). X-ray crystallography studies revealed that all the complexes share similar cyanide-bridged [Fe 2 Co 2 ] square compositions except for the different substituted groups of L ligands, which led to the clearly evidenced intercluster hydrogen bonds between the neighbouring hydroxyl groups in 2 and 3. As a result, 1 remained in the paramagnetic [FeIII,LS2CoII,HS2] state over the whole temperature range, while 2 and 3 showed complete ETCST behaviour with the transition temperatures ( T 1/2 ) being 221 and 294 K, respectively.

The neurodevelopmental process is highly vulnerable to environmental stress from exposure to endocrine-disrupting chemicals. Perfluorinated iodine alkanes (PFIs) possess estrogenic activities, while their potential neurodevelopmental toxicity remains blurry. In the present study, the effects of two PFIs, including dodecafluoro-1,6-diiodohexane (PFHxDI) and tridecafluorohexyl iodide (PFHxI), were investigated in the neural differentiation of the mouse embryonic stem cells (mESCs). Without influencing the cytobiological process of the mESCs, PFIs interfered the triploblastic development by increasing ectodermal differentiation, thus promoting subsequent neurogenesis. The temporal regulation of PFIs in Notch-Hes signaling through the targeting of mmu-miRNA-34a-5p provided a substantial explanation for the underlying mechanism of PFI-promoted mESC commitment to the neural lineage. The findings herein provided new knowledge on the potential neurodevelopmental toxicities of PFIs, which would help advance the health risk assessment of these kinds of emerging chemicals.

A family of molecular capsules, {[(Tp*)Fe(CN) 3 Co(bpy C═N(CH 2 ) 7 N═C bpy)] 2 [X] 2 }·sol ( 1 , X = ClO 4 , sol = 6DMF; 2 , X = PF 6 , sol = 6DMF; 3 , X = OTf, sol = 6DMF; 4 , X = BPh 4 , sol = 2DMF; Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate; bpy = 2,2'-bipyridine), were prepared via the Schiff-base condensation of the aldehyde-substituted bpy (bpy CHO ) and 1,7-diaminoheptane (H 2 N(CH 2 ) 7 NH 2 ). All the complexes contain the same cyanide-bridged cationic square cores ([Fe 2 Co 2 ] 2+ ), which are encapsuled by the flexible alkyl chains. Variable-temperature single-crystal X-ray diffraction, FT-IR spectra, and magnetic studies reveal the abrupt and complete, thermo- and photo-induced electron-transfer-coupled spin transition for 1 - 3 , while the pure high-spin phase for 4 . Such distinct behavior is attributed to the effective long-range cooperative interactions mediated by the intercluster π-π couplings in 1 - 3 , which, however, are significantly blocked in 4 due to the steric effect of interstitial BPh 4 - anions. Furthermore, the shift in the thermally induced transition temperatures of 254 K for 1 , 233 K for 2 , and 187 K for 3 , respectively, is likely correlated to the variable H···O and H···F interactions between the solvent molecules, anions, and the bipyridine ligands of the [Fe 2 Co 2 ] squares, suggesting the significant anion-dependent effect in such a system.

Interactive and responsive materials are dynamic molecular systems that are capable of modulating their behavior and adapting to environment autonomously. Photochromic materials are among the fascinating class of dynamic responsive systems and widely used in molecular switches and optoelectronic devices. However, the phototriggered color changing largely relies on the conformation transformation of the photochromic motif, which significantly limited their usage in organic liquid solutions. Herein, we demonstrate a photochromic organic supramolecular system by using electron-rich N,N-dimethylacetamide (DMA) and electron-deficient naphthalenediimide (NDI) as a donor and acceptor, respectively. In the binary system, the photo-induced electron transfer through lone pair···π interactions pathway leads to dynamic photochromic response not only in the solution but also in the crystalline aggregated state. Furthermore, by incorporating the supramolecules in the polymer matrix, the transparent polymeric film also exhibits rapid photochromic response, which makes it a promisingly interactive and adaptive photochromic material., Competing Interests: The authors declare no competing interests., (© 2021 The Author(s).)

Room-temperature phosphorescence (RTP) was realized for the first time in a polyoxometalate-based charge-transfer (CT) hybrid material bearing polyoxometalates (POMs) as electron-donors (D) and rigid naphthalene diimides (NDIs) as electron-acceptors (A), meanwhile, this hybrid material displayed photochromism as well. The significant D-A anion-π interaction induced an additional through-space charge-transfer pathway. The resulting suitable D-A CT states can efficiently bridge the relatively large energy gap between the NDI-localized 1 π-π* and 3 π-π* states and thus trigger the ligand-localized phosphorescence ( 3 π-π*)., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We developed a model system for blend polymers with electron-donating and -accepting compounds. It is found that the optimal energy conversion efficiency can be achieved when the feature size is around 10 nm. The first reaction method is used to describe the key processes (e.g., the generation, the diffusion, the dissociation at the interface for the excitons, the drift, the injection from the electrodes, and the collection by the electrodes for the charge carries) in the organic solar cell by the dynamic Monte Carlo simulation. Our simulations indicate that a 5% power conversion efficiency (PCE) is reachable with an optimum combination of charge mobility and morphology. The parameters used in this model study correspond to a blend of novel polymers (bis(thienylenevinylene)-substituted polythiophene and poly(perylene diimide-alt-dithienothiophene)), which features a broad absorption and a high mobility. The I-V curves are well-reproduced by our simulations, and the PCE for the polymer blend can reach up to 2.2%, which is higher than the experimental value (>1%), one of the best available experimental results up to now for the all-polymer solar cells. In addition, the dependency of PCE on the charge mobility and the material structure are also investigated.