Optimizing the charge transfer pathway of dopant ions through heterojunction design is a powerful strategy for enhancing semiconductor luminescence. In this context, Dengfeng Peng's group at Shenzhen University developed a high-performance CaF₂/CaZnOS heterojunction mechanoluminescent (ML) material. By precisely controlling the CaF₂-to-CaZnOS ratio, they constructed an efficient heterojunction structure that significantly boosted ML performance. By doping these heterojunctions with lanthanide ions such as Tb³⁺, Pr³⁺, and Yb³⁺, the team has demonstrated highly efficient down-conversion, transforming single energy photons into multiple low-energy photons. This innovation takes advantage of the unique interfacial properties of heterojunction to produce strong luminescence under mechanical stress, offering a promising path toward passive, energy-saving light sources. Moreover, the system achieves quantum cutting, a process that converts one high-energy photon into several lower-energy photons, greatly enhancing luminous efficiency. These advanced heterojunction materials, with their down-conversion-enhanced ML, open new possibilities for a wide range of luminescence-based applications.

High-temperature shock (HTS) successfully converts copper foil into a single-atom copper catalyst within just 0.5 seconds, reaching a reaction temperature of 1700 K and achieving a copper content of 0.54 wt%. This provides a novel and effective method to prevent the aggregation of single atoms and maintain their dispersion.

Water reshapes the Earth through slow, powerful erosion, carving intricate landscapes like caves and pinnacles in soluble rocks such as limestone. An international team from the Faculty of Physics at the University of Warsaw, the University of Florida, and the Institute of Earth Sciences in Orléans has discovered that vertical channels, known as karstic solution pipes, preserve a record of Earth’s climatic history. Their study, published in Physical Review Letters, reveals that these pipes evolve with time into an invariant shape, a fixed, ideal form that remains unchanged as the pipes deepen, encoding ancient rainfall patterns.

Chemical grouting is an effective technique to improve soil structure when it is prone to liquefaction risks during earthquakes. Reliable and uniform grout permeation in heterogeneous soil with low-permeability zones is challenging. Researchers from Shibaura Institute of Technology, Japan, and Asian Institute of Technology, Thailand, have now developed an integrative approach of using Finite Element Method to analyze permeation behavior alongside AI-based permeation prediction, to help engineers improve grouting outcomes in complex soil types.

Chemists at UCL (University College London) and the MRC Laboratory of Molecular Biology have demonstrated how RNA (ribonucleic acid) might have replicated itself on early Earth – a key process in the origin of life.

Chemistry needs to become more sustainable and urgent actions are needed. That is the main message of the Stockholm Declaration on Chemistry for the Future that was launched at the Nobel Prize Museum on 23 May.

Efficient recycling of real-world polyester plastics faces challenges such as separating products from impurities and additives, as well as slow hydrolysis at ambient temperatures. Recently, a research paper proposed a synergistic strategy combining photothermal depolymerization and reforming to overcome these limitations. With a Pt/TiO₂ catalyst, both commercial polylactic acid (PLA) granules and real-world PLA products can be efficiently converted into easily separable H₂, CO and CH₄.