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We reported novel ionic POPs named TE-POPs that exhibited excellent catalytic performance for the CO2 cycloaddition without any additives.

Although the published values of power conversion efficiency (PCE) have increased continuously in recent years for perovskite solar cells (PSCs), improvements in the stability and performance of PSCs with conventional TiO2 or SnO2 electron transport layers (ETLs) remain limited by the presence of nonideal interface defects and low ultraviolet (UV) absorption. In this study, 2-hydroxy-4-methoxy-5-sulfonate-benzophenone (SBP), an inexpensive water-soluble sunscreen raw material, was incorporated into the SnO2 ETL as a UV filter. It was found that the exposure of perovskite to UV light was significantly reduced, and, more importantly, the carbonyl and sulfonic acid groups in the SBP influenced both the perovskite crystallization process and the passivation of defects in the ETL/perovskite film interface. As a result, the PCE of SBP-based devices was increased to 22.54% from 20.78% of the control sample, with a concomitant decrease in the hysteresis. Moreover, the efficiency of champion devices with SBP decreased by less than 5% after 200 h of continuous UV (1.63 mW/cm2, 285 nm) irradiation, while the control group dropped to below 75% of the initial value, thus showing significantly improved stability.

We present an improved inverse-design approach for automatically identifying molecular (or other) systems with optimal values for prechosen properties. The new approach uses SMILES (simplified molecular input line entry system) to describe molecular structures efficiently, a genetic algorithm to optimize the molecules automatically, and the DFTB+ (self-consistent charge density functional tight-binding) method to calculate electronic properties. Thereby, almost every class of materials─even macromolecules or monomers─can be studied easily. Without crossover operators but with only mutation operators, the genetic algorithm is more adaptive to SMILES while keeping its efficiency. DFTB+ is more accurate than the DFTB method used in our previous inverse-design approach for the study of excited states and charge transfer processes. The improved approach is applied to optimize benzene, pyridine, pyridazine, pyrimidine, and pyrazine derivatives for seven electronic properties, which all are highly relevant and important for the performance of molecules in solar cells. We found that for some electronic properties, the precise composition and structure of the backbone have remarkable impacts on the value of the electronic properties and/or on the set of functional groups that leads to the best performance. On the contrary, for other properties, these effects are less pronounced. The reasonable optimal functional groups and/or substitution patterns are reported.

Fluorophenethyl ammonium bromide is introduced in the synthesis of CsPbBr3 QDs and the influence of the fluorination position (ortho, meta, and para) at the benzene ring on the optical properties and stability of CsPbBr3 is systematically evaluated.

Encapsulation of CsPbCl1.5Br1.5 quantum dots (QDs) using LnIII-incorporating polymers (red light, green light emission) obtained by copolymerization of terpyridine-based LnIII complexes with methyl acrylate (MA) is realized for white light emission.

Compared to rigid sensors, soft stain sensors are more suitable for measuring human joint motion because soft sensors are more comfortable to wear. In order to perform more precise measurements, the soft stain sensor should be re-calibrated before performing each measurement in order to eliminate error from donning and doffing. Current calibration methods are often performed by optical motion capture systems (OMCSs). However OMCSs are large and cumbersome, and there is no directly applicable calibration method for soft stain sensors in the measurement of human joint motion. Calibration should be able to be performed quickly and without the need of large equipment such as OMCSs. This paper proposes a calibration method for wearable soft strain sensors that can be done quickly and automatically. The soft sensor structure for self-calibration is parallel and partitioned, and there are integrated primary and redundant sensors. The basic idea of this method is to use redundant sensors to re-calibrate the primary sensor, and only a simple calibration action is required for the self-calibration. After self-calibration, the average errors of measurement were all less than 5 degrees, and the relative errors were all less than 4% for sensor and clothing donned and doffed and long-term sensor migration while wearing. Self-calibration can be performed in only 10 seconds. The results presented that the proposed calibration method is feasible for engineering applications.

Metallocorrole macrocycles that represent a burgeoning class of attractive metal-complexes from the porphyrinoid family, have attracted great interest in recent years owing to their unique structure and excellent performance revealed in many fields, yet further functionalization through incorporating these motifs into porous nanomaterials employing the bottom-up approach is still scarce and remains synthetically challenging. Here, we report the targeted synthesis of porous organic polymers (POPs) constructed from custom-designed Mn and Fe-corrole complex building units, respectively denoted as CorPOP-1(Mn) and CorPOP-1(FeCl). Specifically, the robust CorPOP-1(Mn) bearing Mn-corrole active centers displays superior heterogeneous catalytic activity toward solvent-free cycloaddition of carbon dioxide (CO2) with epoxides to form cyclic carbonates under mild reaction conditions as compared with the homogeneous counterpart. CorPOP-1(Mn) can be easily recycled and does not show significant loss of reactivity after seven successive cycles. This work highlights the potential of metallocorrole-based porous solid catalysts for targeting CO2 transformations, and would provide a guide for the task-specific development of more corrole-based multifunctional materials for extended applications.

The development of a scalable chemical bath deposition (CBD) process facilitates the realization of electron-transporting layers (ETLs) for large-area perovskite solar modules (PSMs). Herein, a method to prepare a uniform and scalable thick Zn

Surface defects of perovskite films are the major sources of nonradiative recombination which limit the efficiency and stability of perovskite solar cells. Surface passivation represents one of the most efficient strategies to solve this problem. Herein, for the first time we designed a porphyrin-involved benzene-1,3,5-tricarboxamide dendrimer (Por-BTA) as a multifunctional interface material between the interface of the perovskite and the hole-transporting layer (spiro-OMeTAD) for the surface passivation of perovskite films. The results suggested that Por-BTA not only efficiently passivated the perovskite surface defects via the coordination of the exposed Pb2+ with the carbonyl unit and basic sites of pyrrole units in Por-BTA but also improved the interface contact and the charge transfer between the perovskite and spiro-OMeTAD ascribed to the strong intermolecular p-p stacking of Por-BTA. It was shown that the PSC devices with the Por-BTA treatment exhibited improved power conversion efficiency with the champion of 22.30% achieved (21.30% for the control devices), which is mainly attributed to the increased short-circuit current density and fill factor. Interestingly, the stability of moisture for the Por-BTA-treated device was also enhanced compared to those without the Por-BTA treatment. This work presents a promising direction toward the design of multifunctional organic molecules as the interface materials to improve the cell performance of PSCs.

Dielectric elastomer sensors (DESs) have demonstrated great potential applications in the fields of human motion capture, rehabilitation training, health monitoring, and soft robotic sensing. However, precise dynamic sensing by DES has not yet been achieved because of the lack of analysis of their dynamic characteristics. This letter analyzes the dynamic characteristics of DESs and finds a remarkable strain delay in dynamic stretching and recovery, which is correlated to historical stretching, deformation speed, and maximum strain. A Burgers four-element model was used to quantitatively analyze the strain delay, and the results are validated by experiment. Strain delay can reduce DES precision, and therefore, a method based on prestretching was proposed to eliminate its influence. Precision of the DES can be remarkably improved after elimination of the strain delay.

The difficulties in the separation of products from the reaction mixture and the recovery of the organic cationic ionic liquids (OCILs) catalysts still need to be addressed. Post modification of the pyridine unit in the covalent organic framework (COF) via the formation of pyridinium salts with the chiral bromoacetate led to the chiral ionic COF with OCIL "immobilized", which was utilized as a heterogeneous catalyst for asymmetric Henry reactions with high yield and excellent stereoselectivity.

Flat and crystalline materials with exceptional nonlinear optical (NLO) properties are highly desirable for their potential applications in integrated NLO photonic devices. Graphdiyne (GD), a new two-dimensional (2D) carbon allotrope, has recently evoked burgeoning research attention by virtue of its tunable bandgap along with a high carrier mobility and extended π-conjugation compared with most conventional optical materials. Here, we experimentally probe the third-order nonlinear optical response of GD dispersed in several common solvents (alcohols) using a femtosecond Z-scan technique. The measured nonlinear optical refractive index is in the order of ∼10−8 cm2/W, which is approximately one order of magnitude higher than that of most 2D materials. In particular, we find that different NLO responses can be observed from GD when dispersed in different solvents, with the strongest NLO response when dispersed in 1-propanol. It is proposed that some intrinsic properties of the solvents, such as the polarity and viscosity, could influence the NLO response of GD materials. Our experimental results confirm the assumptions on the NLO behavior in GD and demonstrate its great potential for future generations of Kerr-effect-based NLO materials and devices.

BODIPY dyes have recently been used for photothermal and photodynamic therapy of tumors. However, complex multi-material systems, multiple excitation wavelengths and the unclear relationship between BODIPY structures and their PTT/PDT efficiency are still major issues. In our study, nine novel BODIPY near-infrared dyes were designed and successfully synthesized and then, the relationships between BODIPY structures and their PTT/PDT efficiency were investigated in detail. The results showed that modifications at position 3,5 of the BODIPY core with conjugated structures have better effects on photothermal and photodynamic efficiency than the modifications at position 2,6 with halogen atoms. Density functional theory (DFT) calculations showed that this is mainly due to the extension of the conjugated chain and the photoinduced electron transfer (PET) effect. By encapsulating BDPX-M with amphiphilic DSPE-PEG2000-RGD and lecithin, the obtained NPs not only show good water solubility and biological stability, but also could act as superior agents for photothermal and photodynamic synergistic therapy of tumors. Finally, we obtained BODIPY NPs that exhibited excellent photothermal and photodynamic effects at the same time under single irradiation with an 808 nm laser (photothermal conversion efficiency: 42.76%, A/A0: ∼0.05). In conclusion, this work provides a direction to design and construct phototherapeutic nanoparticles based on BODIPY dyes for tumor treatment.

Since the widespread presence of metal ions in the ecosystem, especially heavy metal ions that could bring severe damage to living organisms, the development of chemosensors for heavy metal ions is...

Herein, for the first time, we present the successful synthesis of a novel two-dimensional corrole-based covalent organic framework (COF) by reacting the unusual approximately T-shaped 5,10,15-tris(p-aminophenyl)corrole H3 TPAPC with terephthalaldehyde, which adopts desymmetrized hcb topology and consists of a staggered AB stacking structure with elliptical pores. The resultant corrole-based COF, TPAPC-COF, exhibits high crystallinity and excellent chemical stability. The combination of extended π-conjugated backbone and interlayer noncovalent π-π interactions endows TPAPC-COF with excellent absorption capability in the entire visible-light and even near-infrared regions. Moreover, this work suggests the promise of TPAPC-COF as a new class of photoactive material for efficient singlet-oxygen generation with potential photodynamic therapy application as demonstrated by in vitro anticancer studies.

Interfacial adsorption configuration plays a crucial role in influencing the photovoltaic performance of dye-sensitized solar cells (DSSCs), and thus, theoretical investigations are needed to further understand the impacts of different absorption configurations on stoichiometric and defective TiO2(101) surfaces on the short-circuit photocurrent density (JSC) and open-circuit voltage (VOC) of DSSCs. Herein, calculations of isolated dyes and dye/TiO2 systems were performed on the donor-π bridge-acceptor (D-π-A) type porphyrin sensitizers bearing different donor moieties and an α-cyanoacrylic acid anchoring group (T1-3), using DFT and TD-DFT methods. And, for the first time, comparative analysis of interfacial electron transfer (IET) and density of states (DOS) were carried out on dye/TiO2 systems with stoichiometric and defective surfaces to provide further insight into the electronic factors influencing the efficiency of DSSCs, which can well explain the experimental variation trends of JSC and VOC values. It turned out that attachment via the carboxyl and cynao groups in a tridentate binding mode can result in more efficient IET rates and an upshifted conduction band in comparison with those of the bidentate attachment. More interestingly, we found that the adsorption configuration on defective surfaces containing an O2c vacancy induced more upshifted CBM and relatively fast IET, especially for the bonding mode through two O atoms of the carboxyl group.

Blue emitting perovskite ink obtained from cesium lead halide quantum dots bearing chlorine (CsPbClxBr3−x, 0 < x ≤ 3) suffers from the low photoluminescence quantum yield and poor stability. Cesium lead bromine (CsPbBr3) quantum dots free of chlorine have more stable crystal structure and fewer crystal defects. Precise control of crystal sizes and surface passivation components of CsPbBr3 quantum dots is crucial for the best use of quantum confinement effect and blueshift of emission wavelength to blue region. Here, by polymerizing acrylamide under UV-light irradiation to form polymer gel networks in dimethyl sulfoxide (DMSO) with CsPbBr3 precursors and passivating agents trapped, we successfully prepared novel sustained release tablets with different shapes and sizes. Thanks to the limitation of the polymer networks on solvent releasing, the resulting CsPbBr3 quantum dots have the average size of 1.1 ± 0.2 nm. On the basis of the excellent quantum confinement effect and optimized surface passivation, the obtained PQD ink can emit high quality blue light for more than 6 weeks. This work elucidates a new and convenient technique to prepare blue emission perovskite quantum dots ink with high stability and photoluminescence quantum yield and provides a great potential technology for the preparation of perovskite optoelectronic devices.

Graphdiyne (GDY) is a new 2D carbon material different from graphene, and its ideal drug carrying and photothermal therapy efficacy had been noticed recently. Graphdiyne-oxide (GDYO), which few phototherapy researches had been reported, has more oxygen functional groups than GDY. Metal-organic framework materials Fe3O4@UiO-66-NH2 (FU) can covalently connect to GDYO layers and obtain covalent-organic framework-like structures FUGYO. FU enlarged interlamellar space of GDYO, which avoided the aggregation of FUGYO multiple layers. At the same time, more acetylenic bonds and hydrophilic group were exposed, which brings out advantages like stability, hydrophily, high drug-loading, as well as magnetic targeting and better magnetic resonance imaging efficacy. To promote cancer treatment effect and water solubility, we loaded chemotherapy drug doxorubicin (DOX) in FUGYO, then encapsulated FUGYO/DOX in phosphatidylcholine and fluorescent organic polymer BODIPY-PEG (BP) to integrate image-guided and synergistic therapy in one nanoparticle (BPFG/DOX). Due to the unique structure of BPFG/DOX, the π–π interaction between GDYO and BP improved photodynamic therapy efficiency. About 10 μg ml−1 BPFG/DOX have nearly 90% cell lethality to MCF-7 (human breast cancer cell line) cells with laser irradiation. In vivo, BPFG/DOX possessed ideal magnetic targeting and effectively inhibited tumor growth in 6 d. In conclusion, BPFG/DOX not only acts as an excellent tumor theranostic agent but also provides a scheme for applying GDYO in the biomedical region.

Electrophoretic display (EPD) is a type of flexible display which has attracted wide attention. In this work, blue nanosized crystals of cobalt aluminum oxide (CoAl

The corrole unit from the porphyrinoid family represents one of the most important ligands in the field of coordination chemistry, which creates a unique environment allowing for the observation of unusual electronic states of bound metal cations and has shown great promise in various applications. Nevertheless, studies that directly and systematically introduce these motifs in porous crystalline materials for targeting further functionalizations are still lacking. Herein, we report for the first time the construction of two robust corrole-based metal-organic frameworks (MOFs), M6(μ3-O)4(μ3-OH)4(OH)3(H2O)3(H3TCPC)3 (M = Zr for Corrole-MOF-1 and M = Hf for Corrole-MOF-2, H3TCPC = 5,10,15-tris(p-carboxylphenyl)corrole), which are assembled by a custom-designed C2ν-symmetric corrolic tricarboxylate ligand and the unprecedented D3d-symmetric 9-connected Zr6/Hf6 clusters. The resultant frameworks feature a rare (3,9)-connected gfy net and exhibit high chemical stability in aqueous solutions within a wide range of pH values. Furthermore, we successfully prepared the cationic Corrole-MOF-1(Fe) from the iron corrole ligand, which can serve as an efficient heterogeneous catalyst for [4 + 2] hetero-Diels-Alder reactions between unactivated aldehydes and a simple diene, outperforming both the homogeneous counterpart and the porphyrinic MOF counterpart.

With increasing research interests in the field of light-matter interactions, various methods have been developed for regulating nonlinear optical (NLO) materials. However, the design and synthesis of organic molecular materials for second-order nonlinear optics remain a great challenge because of the strict requirement of the materials to possess a noncentrosymmetric structure. In this work, two benzothiadiazole (BTD) derivatives referred to as BTD-H and BTD-F were synthesized, and their NLO properties in the crystalline states were studied. It was found that introducing fluorine into the BTD backbone effectively tuned the crystal packing styles of BTD derivatives to a noncentrosymmetric system for effective second-order NLO responses. Such a strategy to induce the noncentrosymmetric structure by introducing the fluorine atoms and halogen interactions may provide guidance for future engineering of organic NLO molecular materials.