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Progress towards high performance X-ray detection and dynamic imaging applications, including nondestructive inspection, homeland security, and medical diagnostics, requires scintillators with a high light yield, a reasonable decay time, low cost, and eco-friendliness. Recently, copper halide scintillators have drawn tremendous attention due to their outstanding radioluminescence performance. Here, we first employed β-Cs 3 Cu 2 Cl 5 as a high-performance scintillator, with a photoluminescence quantum yield (PLQY) of 94.6%, a radioluminescence light yield of 34 000 ± 4000 photons per MeV, a low detection limit of 81.7 nGy air s -1 , and good operational stability under a total X-ray dose of 174.6 Gy air in air. In addition, this scintillator presents a high spatial resolution of 9.6 lp mm -1 at the modulation transfer function of 0.2 and a superb performance at 60 frames per second in our X-ray imaging system. Overall, this highly efficient scintillator demonstrates outstanding comprehensive performance and shows great potential for broad applications in X-ray detection and dynamic imaging.

Introducing the effect of light into an electrocatalytic system is an effective method to improve electrocatalytic carbon dioxide reduction (CO 2 RR). Here, the composite catalyst (ZIF/Co-C 3 N 4 ) was prepared for the electrocatalytic reduction of carbon dioxide. The Faraday efficiency of the catalytic reduction of CO 2 to CO under light could reach 90.34% at -0.67 V vs. the RHE (reversible hydrogen electrode), which was 30% higher than that obtained under darkness, and the overpotential was reduced by 200 mV. Chemical kinetics experiments and in-situ transient photovoltage (TPV) tests show that the reason for highly efficient CO 2 RR is intermediate CO 2 - formed by activated CO 2 in the electrocatalytic system under light. This work offers a deep insight into the photo-activated electrocatalytic reduction of carbon dioxide, and also opens a new way to devise efficient catalysts for CO 2 RR.

Recently, photothermal therapy (PTT) in the second near-infrared (NIR-II) biowindow has emerged as a promising treatment modality; however, its therapeutic outcomes are still limited by heterogeneous heat distribution and insufficient control of metastatic lesions. Tremendous efforts have been made to overcome the PTT's shortcomings by combining PTT with immunotherapy, but unfortunately current strategies still suffer from low response rates, primary/acquired resistance or severe immune-related adverse events. Herein, a novel photothermal agent and gene co-delivery nanoparticle (CSP), with CuS inside the SiO2 pore channels and PDMAEMA polycation on the outside of SiO2 surface, is explored for tumor localized NIR-II PTT and in situ immunotherapy through local generation of IL-12 cytokine. The resulting CSP integrated with the plasmid encoding IL-12 gene (CSP@IL-12) exhibited good gene transfection efficiency, outstanding NIR-II PTT effect and excellent therapeutic outcomes both in vitro and in vivo. Meanwhile, such an in situ joint therapy modality could significantly induce systemic immune responses including promoting DC maturation, CD8+ T cell proliferation and infiltration to efficiently eliminate possible metastatic lesions through abscopal effects. Hence, this creative combinational strategy of NIR-II PTT and IL-12 cytokine therapy might provide a more efficient, controllable and safer alternative strategy for future photo-immunotherapy.

NaGdF4 is one of the most commonly employed phosphor host matrices for lanthanide doping and is one of the most efficient infrared-to-visible up-conversion fluorescent host materials. Although the structure, morphology and luminescence properties of NaREF4 have been sufficiently investigated, there are very few reported instances of introducing localized order/crystallinity by electron-beam (e-beam) irradiation. In this work, we studied the phase transformation of Gd2O3 from an amorphous to crystalline form via manipulation by e-beam irradiation. The amorphous Gd2O3 occurs as an impurity in the cubic-NaGdF4 nanoparticles (NPs). The structural evolutions, including the transformation from amorphous to crystalline, the recrystallization process and the formation of the graphene@NP core-shell structure, are discussed in detail. We also propose an evolution scheme, in which the e-beam manipulation of the organic-containing NPs induces a subtle structural transformation, depending in principle on the microenvironment of the NPs.

The search for efficient, stable and low-cost electrocatalysts for water splitting is a big challenge faced by energy conversion systems. In this work, Cu3P-Co2P nanocomposites with numerous interfaces are employed as catalysts for water splitting in alkaline solution. The quasi-layer structure of Co2P and the polarized plane of Cu3P endow the nanocomposites with large surface areas and active sites, which substantially favors the intrinsic charge transfer and boosts the catalytic activity. In addition, Cu3P reduces the lattice mismatch between Co2P and nickel foam and then enhances the catalytic stability. For the optimized Cu3P·0.75Co2P catalyst, a low overpotential of 124.6 mV@-20 mA cm-2 is required with a Tafel slope of 65 mV dec-1 for the hydrogen evolution reaction (HER) and an overpotential of 334 mV (at 20 mA cm-2) is required for the oxygen evolution reaction (OER). The potential for the overall-water-splitting@10 mA cm-2 is about 1.55 V with the optimized Cu3P·0.75Co2P catalysts. Theoretical and experimental results both reveal the significance of coupling of Cu3P in the two processes of water-splitting for the Cu3P-Co2P nanocomposite catalyst.

The self-assembly of a high-χ silicon-containing side-chain liquid crystalline block copolymer (LC BCP) in bulk and in thin films is reported, and the structural transition process from the hexagonally packed cylinder (HEX) to the body-centered cubic structure (BCC) in thin films was examined by both reciprocal and real space experimental methods. The block copolymer, poly(dimethylsiloxane-b-11-(4'-cyanobiphenyl-4-yloxy)undecylmethacrylate) (PDMS-b-P(4CNB11C)MA) with a molecular weight of 19.5 kg mol-1 and a volume fraction of PDMS 27% self-assembled in bulk into a hierarchical nanostructure of sub-20 nm HEX cylinders of PDMS with the P(4CNB11C)MA block exhibiting a smectic LC phase with a 1.61 nm period. The structure remained HEX as the P(4CNB11C)MA block transformed to an isotropic phase at ∼120 °C. In the thin films, the PDMS cylindrical microdomains were oriented in layers parallel to the substrate surface. The LC block formed a smectic LC phase which transformed to an isotropic phase at ∼120 °C, and the microphase-separated nanostructure transformed from HEX to BCC spheres at ∼160 °C. The hierarchical structure as well as the dynamic structural transition of the thin films were characterized using in situ grazing-incidence small-angle X-ray scattering and grazing-incidence wide-angle X-ray scattering. The transient morphologies from the HEX to BCC structure in thin films were captured by scanning electron microscopy and atomic force microscopy, and the transition pathway was described.

Interface engineering is an important method to modulate electronic structures for improving the physical properties of semiconductors as well as designing novel devices. Recently, development of flexible electronic devices based on inorganic thin films on flexible substrates, which provides solutions to meet the emerging technological demands, may also expend the methodology of interface engineering. Herein, a semitransparent photodetector based on an indium-tin oxide (ITO)-on-silicon (Si) heterojunction was fabricated on a flexible substrate and investigated under mechanical bending strains. It is found that the barrier height of the heterojunction can be tailored continuously and reversibly from 0.23 eV to 0 eV, corresponding to the Schottky and Ohmic junctions respectively. Meanwhile, the turn-on voltage and the response time of the as-prepared photodetector can be obviously reduced under bending strain, which can be attributed to the modulation of the Si bandgap and hole mobility. Our experimental studies not only shed new light on the strain modulation mechanism of the heterojunction interface, but also pave a prominent way to integrated high-performance flexible photodetectors.

Excellent performance and multifunctional electrocatalysts are of great importance for the development of renewable energy. Here, a multifunctional carbon cloth supported cobalt phosphide (CoP@CC) electrocatalyst was synthesized via a simple electrochemical deposition followed by subsequent phosphorization. This self-standing CoP@CC presents superior HER performance in both acid and alkaline media and excellent OER activity in an alkaline environment. When applied as both anode and cathode catalyst to overall water splitting, CoP@CC only required a low cell voltage of 1.68 V to drive a current density of 10 mA cm -2 , making this catalyst a potential candidate in industrial application. Moreover, inspired by its satisfying ORR activity, CoP@CC was first used as the air-electrode in zinc-air batteries, which outputted an open-circuit potential of 0.6 V and a power density of ∼30 mW cm -2 .

Cost-effective catalysts for electrocatalytic water splitting play a key role in the renewable energy research. Although Pt has been regarded as the best catalyst, its wide applications have been impeded by its high cost and scarce natural abundance. Therefore, decreasing the Pt usage for electrocatalyst design is significant toward the hydrogen evolution reaction (HER). Herein, flower-like Pt nanocrystals were loaded on the surface of nitrogen-doped graphene using Si nanowires as the sacrificial template. The experimental results showed that the optimal Pt nanocrystals/N-doped graphene with superior HER activity and excellent stability only has a low Pt loading of 5.0 wt%. It is noted that the HER mass activity of the Pt nanocrystals/N-doped graphene is 5 fold higher than that of the 20.0 wt% Pt/C commercial catalyst. This optimal catalyst also achieved a low Tafel slope (28.0 mV dec -1 ), large apparent exchange current density (0.989 mA cm -2 ) and high turnover frequency (2.05 s -1 ). This work may provide an effective avenue for developing highly efficient electrochemical catalysts for the HER.

Different types of multi-walled carbon nanotubes (CNTs), synthesized by chemical vapor deposition, are used to fabricate infrared (IR) detectors on flexible substrates based on CNT p-n junctions. It is found that this kind of detector is sensitive to infrared signals with a power density as low as 90 μW mm(-2) even at room temperature. Besides, unlike other devices, the detector with this unique structure can be bent for 100 cycles without any damage and its functionality does not degenerate once it recovers to the initial state. The results give a good reference for developing efficient, low-cost, and flexible IR detectors.

Applying an atomic force microscope, we performed a nanomechanical analysis of morphologically normal cervical squamous cells (MNSCs) which are commonly used in cervical screening. Results showed that nanomechanical parameters of MNSCs correlate well with cervical malignancy, and may have potential in cancer screening to provide early diagnosis.

In this paper, Au/CuS composites were fabricated by a two-step method based on a facile solvothermal approach combined with the in situ reduction. It was demonstrated that the Au/CuS composite not only exhibited excellent peroxidase-like catalytic activity in the oxidation of the typical peroxidases (o-phenylenediamine and diaminobenzidine), but also showed promising SERS performance with remarkable sensitivity and high reproducibility. Based on these properties, the bi-functional Au/CuS composite was employed both as a catalyst for degrading a pollutant (Rhodamine 6G) and a SERS substrate for real-time monitoring of the degradation process quantitatively.