Nano Research最新文献

For the new display technology based on quantum dots (QDs), realizing high-precision arrays of red, green, and blue (RGB) pixels has been a significant research focus at present, aimed at achieving high-quality and high-resolution image displays. However, challenges such as material stability and the variability of process environments complicate the assurance of quality in high-precision patterns. The novel optical patterning technology, exemplified by direct photolithography, is considered a highly promising approach for achieving submicron-level, hyperfine patterning. On the technological level, this method produces patterned quantum dot light-emitting films through a photochemical reaction. Here, we provide a comprehensive review of various methods of QD photolithography patterning, including traditional photolithography, lift off, and direct photolithography, which mainly focused on direct photolithography. This review covers the classification of direct photolithography technologies, summarizes the latest research progress, and discusses future perspectives on the advancement of photolithography technology de-masking.

Mercury is the most toxic and harmful heavy metal pollutant, and it is essential to detect and remove mercury from beverages. Inducing the porphyrin molecules into the chitosan structure, a novel membrane sensor tetrakis(4-carboxyphenyl)porphyrin-grafted chitosan fiber membrane (TCPP-CS) was prepared by electrospinning method and applied to recognize Hg²⁺ contaminant selectively. Compared with other common metal ions (Pb²⁺, Cu²⁺, Fe³⁺, Cr³⁺, Mg²⁺, and Zn²⁺), the colorimetric sensor has specific color development and sensitivity to Hg²⁺ and the detection limit of the sensor reaches 1 × 10⁻⁵ mol·L⁻¹. The response time of the membrane is 5 s, and it can be specifically colored in various pH environments convenient for practical application. Hg²⁺ resulted in a visual color change of the fiber membrane from brown to yellow-green, indicating a potential interaction between the porphyrin-functionalized chitosan fiber membrane and Hg²⁺ ions, and the wavelength shift of the UV–visible spectrum can be observed. It has the advantages of simplicity, rapidity, high selectivity, and high sensitivity, providing a new method for removing and detecting heavy metals in traditional Chinese medicine and drinks.

Luminescent materials with multi-emission features are difficult to be replicated, which are highly desirable for advanced anti-counterfeiting. Here, we report the pioneering synthesis of Mn²⁺/Yb³⁺/Er³⁺ tri-doped Cs₂Ag_0.8Na_0.2InCl₆ double perovskites (MYE-DP), which exhibit photoluminescence (PL) covering from visible to near-infrared (NIR). The PL colors under excitations of 254 and 365 nm are notably different due to the changed relative emission intensities of self-trapped excitons (STEs) and Mn²⁺ d–d transition. Moreover, under the excitation of a NIR laser, the MYE-DP exhibits upconversion (UC) emissions of Mn²⁺ and Er³⁺. After ceasing the excitation, the long-lived trapped electrons can be thermally released to Mn²⁺ and Er³⁺ ions, resulting in both visible and NIR afterglow. Based on multi-modal emissions of the MYE-DP, we demonstrate a five-level anti-counterfeiting strategy, which significantly increases the anti-counterfeiting security. In addition, this work provides valuable insights into the energy transfer between STEs, Mn²⁺, Ln³⁺, and traps, laying a solid foundation for future development of new lead-free perovskites.

VX is a highly toxic organophosphorus nerve agent that the Chemical Weapons Convention classifies as a Schedule 1. In our previous study, we developed a method for detecting organophosphorus compounds using peptide self-assembly. Nevertheless, the self-assembly mechanisms of peptides that bind organophosphorus and the roles of each peptide residue remain elusive, restricting the design and application of peptide materials. Here, we use a multi-scale computational combined with experimental approach to illustrate the self-assembly mechanism of peptide-bound VX and the roles played by residues in different peptide sequences. We calculated that the self-assembly of peptides was accelerated after adding VX, and the final size of assembled nanofibers was larger than the original one, aligning with experimental findings. The atomic scale details offered by our approach enabled us to clarify the connection between the peptide sequences and nanostructures formation, as well as the contribution of various residues in binding VX and assembly process. Our investigation revealed a tight correlation between the number of Tyrosine residues and morphology of the assembly. These results indicate a self-assembly mechanism of peptide and VX, which can be used to design functional peptides for binding and hydrolyzing other organophosphorus nerve agents for detoxification and biomedical applications.

Psoriasis is a chronic skin disease characterized by the hyperproliferation of keratinocytes and an overactive autoimmune response. Photodynamic therapy (PDT) has been established as a promising intervention for alleviating psoriasis. However, the current transdermal delivery of photosensitizers is inefficient and imprecise. In this study, we developed a foamed microemulsion nanodroplets system containing chlorin e6 (Ce6 FM), exhibiting precise epidermal targeting and retention, which targeted the aberrantly proliferating epidermal cells at psoriatic skin lesions and avoided the damage to the normal cutaneous cells. Upon application in a psoriatic mouse model, Ce6 FM efficiently induced keratinocyte apoptosis by generating reactive oxygen species under laser. Furthermore, Ce6 FM-based PDT activated the cyclooxygenase-2-induced immunosuppressive pathway in keratinocytes, resulting in the amelioration of the autoimmune microenvironment in psoriatic skin. Additionally, Ce6 FM-based PDT did not induce skin damage or atrophy associated with non-targeted halometasone treatment. Overall, Ce6 FM-based PDT holds promise as an effective, safe and compliant strategy for psoriasis treatment.

Traditional iridium (Ir) oxide catalysts have faced significant limitations in water electrolysis, particularly under acidic conditions where instability and degradation severely restrict the efficiency of the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). To overcome these challenges, this study successfully synthesized highly dispersed IrPtPdNi alloy nanoparticles on a graphene oxide support using a vertically moving reactor, demonstrating exceptional performance in water electrolysis. These nanoparticles, synthesized via a fast-moving bed pyrolysis method, combine iridium, platinum, palladium, and nickel. They exhibit lower overpotentials in OER and comparable performance in HER to commercial catalysts, while also offering enhanced stability. These results surpass the limitations of traditional catalysts, marking significant progress toward more efficient and sustainable hydrogen production technologies. This advancement is expected to contribute significantly to the development of sustainable energy systems by innovatively enhancing the performance of catalysts in the electrochemical water-splitting process.