Highly porous metal oxide polycrystalline nanowire films with superior performance in gas sensors

In this work, we report for the first time a simple two-step route to fabricate a novel porous metal oxide film composed of polycrystalline nanowires with ultra-small nanoparticles, good interconnectivity between nanoparticles, and a high density of ultra-fine nanopores. The as-prepared metal oxide films combine the advantages of small crystal size, high surface-to-volume ratio, and one-dimensional-nanowire-induced unique charge transport paths (with correspondingly high interconnectivity). Taking In2O3 as an example, porous In2O3 films, composed of polycrystalline In2O3 nanowires with ultra-small nanocrystals (less than 10 nm) and a high density of ultra-fine nanopores (1.6–3.1 nm), have shown very high sensitivity and good reproducibility towards ethanol gas, which are 10–20 times higher than for In2O3 octahedra and commercial SnO2 thick films. The response/recovery speeds of the as-prepared porous In2O3 films are also 5–6 times higher than for In2O3 octahedra, SnO2 nanobelts, and commercial SnO2 thick films. We believe that such metal oxide flexible films made from highly porous nanowires will replace their traditional thick film counterparts, not only in gas sensors but also in other functional devices, such as batteries, supercapacitors, solar cells, etc

Hydrogen-bonded supramolecular adhesives: Synthesis, responsiveness, and application

Adhesive bonding to diverse substances is vital to a great number of the established, cutting-edge and emerging applications. We have witnessed, in the last few years, the transformative progress in achieving robust adhesive bonding and tunable debonding behavior, which mostly employing the supramolecular forces. Among the diverse supramolecular forces, the contribution of hydrogen-bonds (H-bonds) to adhesives, on the modality of directionality, selectivity and sensitivity, can function as nano-scaled bonding agents for improved interfacial interactions, thus paved novel perspectives to the design and creation of glue materials with outstanding performance. On account of the dynamic and reversible feature, a characteristic principally determined for H-bonding (macro)molecules could be employed as adhesive platform for affording outstanding attaching, connecting and on demand disconnecting, arising from the combination of adhesion/cohesion process via H-bonding interactions and the responsive characteristics. Thus, H-bonded adhesives with abundant diverse molecular configuration furnish a rich toolbox that can fulfill universal yet specific needs with unique advantages, demonstrating great opportunities for fundamental researches and practical applications. Herein we outline and summarize the design and creation of H-bonded adhesives, responsive attaching/detaching, and applications in advanced materials. We propose the guidance for further designing H-bonded adhesives, in concert with biomedical science, physics, mechanical and electric, informatics or robotics of promising future

TiC-induced nanoscale Cu-rich re-precipitation mechanism under welding thermal cycles and its effect on the strength-toughness of heat affected zones

In order to solve the softening problem of welding heat affected zone (HAZ) for Cu-bearing steel caused by the dissolution of Cu-rich particles, TiC was utilized to induce the Cu-rich re-precipitation. With the peak temperature increased from 780 °C (ICHAZ) to 950 °C (FGHAZ), the size of 9R–Cu increases from 4 nm to 5 nm, accompanied with the increment of volume fraction from 0.6% to 1.0%. Phase field simulations indicate that TiC repels Cu atoms into γ-Fe matrix and promotes the formation of Cu-rich clusters. Then, Cu-rich clusters provide more nucleation sites for Cu-rich particles, which contributed to the re-precipitation of refined 9R–Cu. Due to the disappearance of coarse grain boundary Cu-rich particles and formation of fresh lath bainite, re-precipitated Cu-rich particles provided precipitation strengthening value of 237 MPa and 298 MPa without decreasing the low temperature toughness for ICHAZ and FGHAZ. The yield strength and absorbed energy at −40 °C of HAZs exceed 1000 MPa and 120J, respectively

Heterogeneous ZnS hollow urchin-like hierarchical nanostructures and their structure-enhanced photocatalytic properties

Hexagonal wurtzite ZnS nanowires radially arrayed on cubic zinc-blende ZnS hollow spheres have been successfully achieved for the first time, and such novel heterogeneous ZnS hollow urchin-like hierarchical nanostructures show greatly enhanced photocatalytic properties due to their two-phase enhanced light-harvesting and high surface-to-volume ratio

Utilizing cost-effective pyrocarbon for highly efficient gold retrieval from e-waste leachate

Abstract Addressing burdens of electronic waste (E-waste) leachate while achieving sustainable and selective recovery of noble metals, such as gold, is highly demanded due to its limited supply and escalating prices. Here we demonstrate an environmentally-benign and practical approach for gold recovery from E-waste leachate using alginate-derived pyrocarbon sorbent. The sorbent demonstrates potent gold recovery performance compared to most previously reported advanced sorbents, showcasing high recovery capacity of 2829.7 mg g−1, high efficiency (>99.5%), remarkable selectivity (K d ~ 3.1 × 108 mL g−1), and robust anti-interference capabilities within environmentally relevant contexts. The aromatic structures of pyrocarbon serve as crucial electrons sources, enabling a hydroxylation process that simultaneously generates electrons and phenolic hydroxyls for the reduction of gold ions. Our investigations further uncover a “stepwise” nucleation mechanism, in which gold ions are reduced as intermediate gold-chlorine clusters, facilitating rapid reduction process by lowering energy barriers from 1.08 to −21.84 eV. Technoeconomic analysis demonstrates its economic viability with an input-output ratio as high as 1370%. Our protocol obviates the necessity for organic reagents whilst obtaining 23.96 karats gold product from real-world central processing units (CPUs) leachates. This work introduces a green sorption technique for gold recovery, emphasizing its role in promoting a circular economy and environmental sustainability

TRPM2 promotes pancreatic cancer by PKC/MAPK pathway

Abstract The mechanism of pancreatic cancer (PA) is not fully understanded. In our last report, TRPM2 plays a promising role in pancreatic cancer. However, the mechanism of TRPM2 is still unknown in this dismal disease. This study was designed to investigate the role and mechanism of TRPM2 in pancreatic cancer. TRPM2 overexpressed and siRNA plasmid were created and transfected with pancreatic cancer cell line (BxPC-3) to construct the cell model. We employed CCK-8, Transwell, scratch wound, and nude mice tumor-bearing model to investigate the role of TRPM2 in pancreatic cancer. Besides, we collected the clinical data, tumor tissue sample (TT) and para-tumor sample (TP) from the pancreatic cancer patients treated in our hospital. We analyzed the mechanism of TRPM2 in pancreatic cancer by transcriptome analysis, western blot, and PCR. We blocked the downstream PKC/MEK pathway of TRPM2 to investigate the mechanism of TRPM2 in pancreatic cancer by CCK8, scratch wound healing, and transwell assays. Overexpressed TRPM2 could promote pancreatic cancer in proliferation, migration, and invasion ability in no matter the cell model or nude mice tumor-bearing model. TRPM2 level is highly negative correlated to the overall survival and progression-free survival time in PA patients, however, it is significantly increased in PA tissue as the tumor stage increases. The transcriptome analysis, GSEA analysis, western-blot, and PCR results indicate TRPM2 is highly correlated with PKC/MAPK pathways. The experiments of PKC/MEK inhibitors added to TRPM2 overexpressed BxPC-3 cell showed that significant inhibition of PA cells happened in CCK8, transwell, and wound-healing assay. TRPM2 may directly activate PKCα by calcium or indirectly activate PKCε and PKCδ by increased DAG in PA, which promote PA by downstream MAPK/MEK pathway activation