Chemical Communications最新文献

Designed to reflect or absorb near-infrared (NIR) light, smart NIR coatings have emerged as a transformative and sustainable solution in healthcare and biomedical fields. As longer wavelength allow for reduced scattering and absorption, NIR light exhibits superior penetration through biological tissues when compared to visible light, making NIR-based technologies extremely useful for both therapeutics and diagnostics. NIR coatings can be utilized for non-invasive imaging to monitor and control the performance of implantable devices, including drug release, biofilm disintegration and infection prevention, providing several advantages over the traditional drug administration, sterilization or antibiotic strategies. In this review, we explore key advantages of using NIR coatings in medical devices, highlighting the impact of their use on device efficiency, operational lifespan and performance, and their role in reducing the environmental impact of medical devices. Using recent examples, we identify pathways by which the use of NIR coatings can continue to drive the improvements in the key performance characteristics of medical devices while supporting the principles of circular economy, highlighting critical challenges and opportunities for this family of technologies.

Photocatalytic CO₂ conversion represents a groundbreaking approach to addressing two of the most pressing global challenges: mitigating CO₂ emissions and producing sustainable fuels. This review article provides an in-depth summary of the achievements made in the last five years to enhance the efficiency and selectivity of CO₂ photoreduction typically on photocatalytic materials (not including organic molecules or coordination compounds), with specific focus on producing high-value hydrocarbon fuels including methanol, ethanol, ethene, and ethane. Specific strategies for promotion of CO₂ photoconversion performance were discussed, including (1) regulation of hydrophilic and hydrophobic surfaces of photocatalytic materials, (2) construction of heterojunctions; (3) dual-site engineering, (4) design of asymmetric structures; (5) doping; (6) creation of single-atom catalysis systems; (7) vacancy engineering; (8) loading of cocatalysts; (9) surface reconstruction; and (10) modulation of Cu valence states in typical photocatalytic materials. Finally, challenges and perspectives are also presented, including challenges of low efficiency, poor selectivity, and catalyst stability under realistic conditions, along with future perspectives focusing on developing highly active, selective, and durable catalysts through advanced materials engineering and optimized reaction environments.

A selection of five donor/acceptor-functionalized radiaannulenes was efficiently synthesized via a series of palladium-catalyzed couplings. These donor/acceptor segments of the elusive 6,6,12-graphyne allotrope are strong chromophores and undergo reductions into dianions corrrelating with Hammett substituent constants. Crystal data reveal planar structures of the cyclic cores, but twisting of the aryl substituents with torsional angles independent on the donor/acceptor character.

The precursor structure inevitably affects the structure of the derived hard carbon (HC), and a comprehensive understanding of their relationship can help promote the research and application of high-performance HC materials. This work is the first to investigate the impact of precursor crystal structure on the derived HC. The transformation of cellulose polymorphs alters their molecular chain packing arrangements and hydrogen bond networks, ultimately affecting the microstructure and electrochemical performance of the derived HCs.

Binary nanoparticle superlattices (BNSLs) enable the construction of new mesomaterials by combining the properties of two nanoparticle building blocks. We demonstrate two-dimensional (2D) BNSLs from silver nanocubes and gold nanospheres, analyzing their interparticle and orientational orders. Our experimental mesophase diagram identifies an isotropic phase that serves as a transition state to others.

Electrocatalytic nitrite (NO₂^-) reduction is a promising and eco-friendly method for ammonia (NH₃) production. Here, carbon-coated MoO₂ nanoparticles decorated on reduced graphene oxide (MoO₂@C/RGO) are reported to be an effective electrocatalyst for NO₂^- reduction to NH₃. The outer carbon shell not only effectively enhances the stability of the electrocatalyst but also promotes the charge transfer during the NO₂^- reduction process, thereby significantly improving the catalytic performance. In neutral media, MoO₂@C/RGO provides a high NH₃ yield of 17.64 ± 0.10 mg h^-1 cm^-2 and a high FE of 95.79% ± 0.50% at -0.9 V. Furthermore, a Zn-NO₂^- battery with MoO₂@C/RGO exhibits a peak power density of 2.125 mW cm^-2 and an open circuit voltage of 1.33 V.

A highly diastereoselective Pd-catalyzed sequential reaction of ortho-iodophenyl-ynones, propargylic ethers and maleimides is developed for efficient synthesis of tetracyclic succinimide derivatives containing three contiguous stereocenters and one exocyclic double bond. The reaction proceeds through Pd-catalyzed cross-coupling and propargyl Alder-ene reactions to generate a reactive indenone-allene intermediate, which undergoes an intermolecular Diels-Alder cycloaddition with maleimide to deliver a densely functionalized product. In addition, a formal four-component reaction was observed for generating polycyclic products bearing two succinimide motifs.