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Superlattice deformation in PbS quantum dot thin films introduced by uniaxial strain: In situ GISAXS study on the correlation of morphology and photoluminescence.

The function of molecular chirality in collagen self-assembly was presented.

Self-assembly is one of the most vital molecular behaviors of natural collagen, which plays a prominent role in the design and fabrication of collagen-based biomaterials. However, an efficient and sensitive assay for monitoring collagen self-assembly is still lacking. Herein, we developed a quantum dot (QD)-based fluorescence sensing platform and applied it to monitor collagen self-assembly. Before collagen self-assembly, we observed a strong fluorescent signal when ZnCdSe/ZnS QDs were introduced to grass carp skin collagen (GCSC). After self-assembly, the formation of collagen fibril networks induced the aggregation of QDs, resulting in the fluorescence quenching of QDs and a significant decrease in the intensity of fluorescence. Moreover, the quenching efficiency was found to be linearly dependent with GCSC concentration in the range of 0.1–1 mg mL−1, with a detection limit of 0.1 mg mL−1. In addition, the proposed strategy displayed excellent specificity and wide applicability. These results provide guidance for the design of collagen-based biomaterials and help to deeply understand the mechanism behind collagen self-assembly.

Xenogeneic collagen co-assembly (XCCA) is a novel and efficient strategy for improving and regulating the performance of collagen assembled products. However, the effect of collagen molecular structures on XCCA has long been neglected and remains unclear. Herein, we investigated the telopeptide effect of collagen on XCCA by employing grass carp skin collagen (GCSC) with two different structures (tropocollagen and atelocollagen) and porcine skin collagen (PSC). Kinetic analysis showed that the co-assembly rate of PSC and grass carp skin atelocollagen (AC-GCSC) was faster than that of PSC and grass carp skin tropocollagen (TC-GCSC). Based on this observation, we further obtained different concentration dependences of XCCA by the alteration of telopeptide. Compared with PSC/TC-GCSC co-assembly, PSC/AC-GCSC co-assembly exhibited a higher sensitivity and a lower detection limit. Furthermore, telopeptide promoted the fabrication of thicker fibrils and improved the mobility of gels.

A sensitive and robust electrochemical aptasensor for determining dopamine (DA) was developed using a grass carp skin collagen-graphene oxide (GCSC-GO) composite as a transducer and a label-free aptamer as a biological recognition element for the first time. In order to fabricate this sensor, the GCSC-GO composite was firstly prepared by ultra-sonication method and characterized by atomic force microscope, infrared spectroscopy, Raman spectroscopy, and electrochemical impedance spectroscopy. Subsequently, a label-free DA-binding aptamer was immobilized through strong interaction between collagen and aptamer. The fabricated electrochemical aptasensor was used to determine DA by differential pulse voltammetry. The results indicated that the peak current changes of the developed aptasensor was linear relationship with the DA concentrations from 1 to 1000 nM, and the detection limit was 0.75 nM (S/N = 3). Moreover, the fabricated aptasensor showed high selectivity for DA. More importantly, the obtained aptasensor exhibited satisfactory recovery toward DA in human serum specimens with excellent stability.

Directly growing perovskite single crystals on charge carrier transport layers will unravel a promising route for the development of emerging optoelectronic devices. Herein, in situ growth of high‐quality all‐inorganic perovskite (CsPbBr3) single crystal arrays (PeSCAs) on cubic zinc oxide (c‐ZnO) is reported, which is used as an inorganic electron transport layer in optoelectronic devices, via a facile spin‐coating method. The PeSCAs consist of rectangular thin microplatelets of 6–10 µm in length and 2–3 µm in width. The deposited c‐ZnO enables the formation of phase‐pure and highly crystallized cubic perovskites via an epitaxial lattice coherence of (100)CsPbBr3∥(100)c‐ZnO, which is further confirmed by grazing incidence wide‐angle X‐ray scattering. The PeSCAs demonstrate a significant structural stability of 26 days with a 9 days excellent photoluminescence stability in ambient environment, which is much superior to the perovskite nanocrystals (PeNCs). The high crystallinity of the PeSCAs allows for a lower density of trap states, longer carrier lifetimes, and narrower energetic disorder for excitons, which leads to a faster diffusion rate than PeNCs. These results unravel the possibility of creating the interface toward c‐ZnO heterogeneous layer, which is a major step for the realization of a better integration of perovskites and charge carrier transport layers., In situ growth of high‐quality CsPbBr3 perovskite single crystal arrays directly on an electron transport layer of cubic zinc oxide (c‐ZnO) via a facile spin‐coating method is presented. CsPbBr3 and c‐ZnO can match moderately attributed to the epitaxial lattice coherence. The interface toward c‐ZnO heterogeneous layer is a major step toward the realization of better integration of perovskites and inorganic transport layers.

Colloidal PbSe nanocrystals (NCs) have gained considerable attention due to their efficient carrier multiplication and emissions across near-infrared and short-wavelength infrared spectral ranges. However, the fast degradation of colloidal PbSe NCs in ambient conditions hampers their widespread applications in infrared optoelectronics. It is well-known that the inorganic thick-shell over core improves the stability of NCs. Here, we present the synthesis of PbSe/PbS core/shell NCs showing wide spectral tunability, in which the molar ratio of lead (Pb) and sulfur (S) precursors, and the concentration of sulfur and PbSe NCs in solvent have a significant effect on the efficient PbS shell growth. The infrared light-emitting diodes (IR-LEDs) fabricated with the PbSe/PbS core/shell NCs exhibit an external quantum efficiency (EQE) of 1.3 % at 1280 nm. The ligand exchange to optimize the distance between NCs and chloride treatment are important processes for achieving high performance on PbSe/PbS NC-LEDs. Our results provide evidence for the promising potential of PbSe/PbS NCs over the wide range of infrared optoelectronic applications.

This paper reviews recent progress in the synthesis of near-infrared (NIR) lead chalcogenide (PbX; PbX=PbS, PbSe, PbTe) quantum dots (QDs) and their applications in NIR QDs based light emitting diodes (NIR-QLEDs). It summarizes the strategies of how to synthesize high efficiency PbX QDs and how to realize high performance PbX based NIR-QLEDs., 25 pages, 16 figures, review