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Radiodynamic therapy (RDT), which produces 1O2and other reactive oxygen species (ROS) in response to X-rays, can be used in conjunction with radiation therapy (RT) to drastically lower X-ray dosage and reduce radio resistance associated with conventional radiation treatment. However, radiation–radiodynamic therapy (RT–RDT) is still impotent in a hypoxic environment in solid tumors due to its oxygen-dependent nature. Chemodynamic therapy (CDT) can generate reactive oxygen species and O2by decomposing H2O2in hypoxic cells and thus potentiate RT–RDT to achieve synergy. Herein, we developed a multifunctional nanosystem, AuCu-Ce6-TPP (ACCT), for RT–RDT–CDT. Ce6 photosensitizers were conjugated to AuCu nanoparticles via Au–S bonds to realize radiodynamic sensitization. Cu can be oxidized by H2O2and catalyze the degradation of H2O2to generate •OH through the Fenton-like reaction to realize CDT. Meanwhile, the degradation byproduct oxygen can alleviate hypoxia while Au can consume glutathione to increase the oxidative stress. We then attached mercaptoethyl-triphenylphosphonium (TPP-SH) to the nanosystem, targeting ACCT to mitochondria (colocalization Pearson coefficient 0.98) to directly disrupt mitochondrial membranes and more efficiently induce apoptosis. We confirmed that ACCT efficiently generates 1O2and •OH upon X-ray irradiation, resulting in strong anticancer efficacy in both normoxic and hypoxic 4T1 cells. The down-regulation of hypoxia-inducible factor 1α expression and reduction of intracellular H2O2concentrations suggested that ACCT could significantly alleviate hypoxia in 4T1 cells. ACCT-enhanced RT–RDT–CDT can successfully shrink or remove tumors in radioresistant 4T1 tumor-bearing mice upon 4 Gy of X-ray irradiation. Our work thus presents a new strategy to treat radioresistant hypoxic tumors.

A new copper-catalyzed selective synthesis of N1- and N2-oxyalkylated 1,2,3-triazoles has been developed through a three-component reaction of alkynes, TMSN3, and ethers. Through this methodology, a series of N1- and N2-oxyalkylated 1,2,3-triazoles could be efficiently and regioselectively obtained from simple and readily available starting materials with favorable functional group tolerance.

Here we reported the doping of graphdiyne in P3CT-K in MAPbI3perovskite solar cells as hole-transport materials. The doping could improve the surface wettability of P3CT-K, and the resulting perovskite morphology was improved with homogeneous coverage and reduced grain boundaries. Simultaneously, it increased the hole-extraction mobility and reduced the recombination as well as improved the performance of devices. Therefore, a high efficiency of 19.5% was achieved based on improved short-circuit current and fill factor. In addition, hysteresis of the J–Vcurve was also obviously reduced. This work paves the way for the development of highly efficient perovskite solar cells.

This work demonstrates a novel photovoltaic application in which graphdiyne (GD) can be employed as a host material in a perovskite active layer for the first time. In the device fabrication, the best molar ratio for active materials is verified as PbI2/MAI/GD being 1:1:0.25, yielding a peak power-conversion efficiency of 21.01%. We find that graphdiyne, as the host material, exerts significant influence on the crystallization, film morphology, and a series of optoelectronic properties of the perovskite active layer. A uniform MAPbI3film with highly crystalline qualities, large domain sizes, and few grain boundaries was realized with the introduction of graphdiyne. Moreover, the current–voltage hysteresis was negligible, and device stability was significantly improved as well. The results indicate that graphdiyne as the host active material presents great potential for the enhancement of the performance of perovskite solar cells.

In perovskite solar cells, inorganic hole transport materials have attracted intense attention because of the properties of high chemical stability, hole mobility and low cost. However, most of the inorganic hole conductors exhibit low performance compared with organic hole transport materials. In this study, a facile solution method was developed to prepare a V2O5film combined with P3CT-K thus forming a bilayer structure as hole transport layers in inverted CH3NH3PbI3solar cells. It was found that the hole transport bilayer not only increased the rate of extraction charge but also reduced charge recombination compared with the P3CT-K only based device. As a result, the power conversion efficiency of inverted CH3NH3PbI3solar cells based on the bilayer was boosted up to the optimal value of 19.7% (average value: 19.0%). Furthermore, the device maintained an efficiency of more than 86% through one-month follow-up, in which the dense and hydrophobic V2O5film accounted for the improved device stability.

Ternary CuZnS nanocrystals (NCs) are synthesized via a facile, scalable, noninjection method at low temperatures for the first time, wherein sodium ascorbate plays the dual roles of reducing agent and capping ligand in the preparation process. These NCs can be dispersed well in a polar solvent like dimethyl sulfoxide, and the average size is ∼4 nm as measured by transmission electron microscopy. The results of X-ray diffraction and X-ray photoelectron spectroscopy indicate that the crystal structure of CuZnS NCs displays covellite CuS-like structure and the Zn element partly occupies the Cu position. Also, the crystal structure of CuZnS NCs is completely converted from a covellite CuS structure into a digenite Cu9S5structure when the NCs are treated above 350 °C. Moreover, CuZnS NCs demonstrate favorable hole transport properties. When it is employed in MAPbI3-based perovskite solar cells as a hole transport layer, a peak power conversion efficiency of 18.3% is achieved. Simultaneously, the devices based on CuZnS exhibit a remarkably reduced J–Vhysteresis. The results indicate that CuZnS is a promising hole transport layer for enhancing perovskite solar cell performance and presents great potential for optoelectronic applications, as well.

The molecular structure of cathode interface modification materials can affect the surface morphology of the active layer and key electron transfer processes occurring at the interface of polymer solar cells in inverted structures mostly due to the change of molecular configuration. To investigate the effects of spatial configuration of the cathode interfacial modification layer on polymer solar cells device performances, we introduced two novel organic ionic salts (linear NS2 and three-dimensional (3D) NS4) combined with the ZnO film to fabricate highly efficient inverted solar cells. Both organic ionic salts successfully decreased the surface traps of the ZnO film and made its work function more compatible. Especially NS4 in three-dimensional configuration increased the electron mobility and extraction efficiency of the interfacial film, leading to a significant improvement of device performance. Power conversion efficiency (PCE) of 10.09% based on NS4 was achieved. Moreover, 3D interfacial modification could retain about 92% of its initial PCE over 160 days. It is proposed that 3D interfacial modification retards the element penetration-induced degradation without impeding the electron transfer from the active layer to the ZnO film, which significantly improves device stability. This indicates that inserting three-dimensional organic ionic salt is an efficient strategy to enhance device performance.

In this work, PC61BM:SnO2electron transport layers (ETLs) were applied in inverted CH3NH3PbI3perovskite solar cells, and a high power conversion efficiency of 19.7% could be obtained. It increased by 49.0% in comparison with the device based on PC61BM-only ETL (13.2%). SnO2nanocrystals with excellent dispersibility were employed here to fill the pinholes and cover the valleys of PC61BM layer, forming smooth and compact PC61BM:SnO2layers. Simultaneously, the electron traps caused by deep-level native defects of SnO2were reduced by PC61BM, proved by the space charge limited current analysis. Thus, PC61BM:SnO2ETLs can inhibit both of the defects in PC61BM and SnO2layers which contribute to the electron transport improvement and reduce the recombination loss. Moreover, the device stability based on the bilayer was significantly improved in comparison with the PC61BM-only device and the performance of 85% could be maintained after 1 month.

The properties of electron transport layers play a crucial role in determining the performance of perovskite solar cells. Here we reported that graphdiyne doped in both PCBM and ZnO films of perovskite solar cells with an inverted structure based on MAPbI3for the first time. A high efficiency of 20.0% was achieved in MAPbI3perovskite solar cells. Moreover, the J-Vhysteresis and stability were significantly improved as well. It was found that dual doping graphdiyne not only increased electrical conductivity, electron mobility, and charge extraction ability in the electron transport layers but also improved film morphology of the electron transport layers and reduced charge recombination which contribute to fill factor improvement. Therefore the results indicate that dual doping graphdiyne is a promising strategy to enhance perovskite solar cells performance.

Dendrimers are highly branched macromolecules with well-defined molecular structures and nanometer-scale dimensions. Dendrimer-supported catalysts behave homogeneously during the reaction, but most of them can be separated from the reaction medium via solvent precipitation. Their catalytic properties can be fine-tuned by adjusting the structure, size and shape of the dendrimers. In many cases, interesting dendrimer effects were observed, including increased or decreased the catalytic activity, stability and enantioselectivity. This review focuses on the recent decade of progress concerning the dendrimer-supported catalysts in the following reactions: (a) asymmetric hydrogenation and hydrosilylation; (b) asymmetric transfer hydrogenation; (c) carbon-carbon bond-forming reactions; (d) miscellaneous reactions.

Several derivatives of N,N-bis(3,5-di-tert-butyl-4-hydroxybenzyl)-N-alkylamines were isolated in the reduction of the imines obtained from 3,5-di-tert-butyl-4-hydroxylbenzaldehyde and primary amines. Experimental results showed that they were transformed from the corresponding 2,6-di-tert-butyl-4-alkylaminomethylphenols.

Lithium-sulfur (Li–S) battery represents one of the most promising candidates for next-generation energy storage devices due to its superhigh energy density. However, its practical utilization is seriously hampered by shuttle effect of lithium polysulfides (LiPSs). In this work, sandwich-structured Ti4O7-carbon nanofibers/Ti4O7/Ti4O7-carbon nanofibers (TC/T/TC) is developed as a functional interlayer to efficiently inhibit shuttle effect for high-performance Li–S batteries. The free-standing TC/T/TC interlayer with favourable flexibility is fabricated through alternately adopting electrospinning and spraying technique, then followed by in-situ high temperature carbonization and reduction. The resulting interlayer presents excellent physical-blocking and chemical-trapping effects for LiPSs since it has a dense middle layer of polar and conductive Ti4O7with sufficient physicochemical sites for LiPSs trapping and conversion. Besides, the porous surface layers of Ti4O7-carbon nanofibers can provide enough space to restrain volume expansion and recycle the cathode fragments. Furthermore, the highly conductive interlayer can serve as a front current collector to reduce resistance and accelerate redox process. When applied to Li–S battery, CMK3/S cathode (sulfur areal density, 2 mg/cm2) with the TC/T/TC interlayer exhibits decent cycling capability and rate performance. It delivers an initial specific capacity of 1129 mAh g−1and its capacity remains at 686 mAh g−1after 500 cycles at 1 C rate. More excitingly, its initial specific capacity reaches 738 mAh g−1 at 3 C rate, and the capacity maintains at 481 mAh g−1even after 3500 ultra-long cycles, with a high capacity retention of 65.2% and extremely low capacity decay of 0.00995% per cycle. The new type of interlayer will possess a great promise to find its practical application in Li–S batteries.

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