Optical biosensors are important tools for basic research and non-invasive diagnostics. Carbon nanotubes are versatile near-infrared fluorescent and non-bleaching materials that can be chemically functionalized to detect a broad variety of biomolecules. This Review highlights chemical design strategies and provides a comprehensive overview of the recent developments in this dynamic field.

A comprehensive review on dendritic mesoporous silica nanoparticles (DMSNs) with radial pores is provided. Perspectives into their formation mechanisms, synthesis–structure–property relationships and future research directions with a focus on biomedical applications are presented.

Porphyrin-based metal–organic frameworks can be designed and constructed for powerful biomedical applications. Recent progress and future expectations are discussed in this Review.

Cancer therapy: Recent progress in 2D nanomaterials for photothermal therapy including their optical properties, synthesis methods, surface modification, and applications is reviewed. The unique properties and advantages of 2D nanomaterials have been successfully used in photothermal therapy and combined photothermal therapy. This application will continue to be attractive and needs further exploration.

Taking the lead: This Review summarizes recent advances in widely studied lead-free halide perovskite nanocrystals, centering on understanding their crystal structures, synthesis methods, environmental stability, and optical properties. The challenges in this rapidly evolving field and opportunities to further improve the quality and stability of these nanocrystals are also provided.

Radical approach: Recent rapid developments in chemodynamic therapy using the Fenton or Fenton-like reactions to generate ^.OH at tumour sites are discussed in depth in this Minireview. Emphasis is placed on the strategies designed to enhance therapeutic efficiency, providing guidelines for potential clinical translation.

Single-atom nanozymes contain atomically active sites and they are similar to natural metalloenzymes; they hold great promise in sensing, degradation of organic pollutants, and in therapeutic applications. Moreover, single-atom catalysts help to unravel structure–activity relationships and thereby uncover the nature of biocatalysts at a single-atom scale.

Electrochemistry in 3D: Three-dimensional transition-metal dichalcogenide architectures have shown great promise for electrochemical energy storage and conversion. This Review summarizes the commonly used strategies for the construction of such architectures, as well as their application in rechargeable batteries, supercapacitors, and electrocatalytic hydrogen evolution.

PDT beats hypoxia: Novel and robust strategies, which can improve the therapeutic efficacy of photodynamic therapy (PDT) for hypoxic tumors, have been widely investigated in recent years. These efforts have led to the development of new approaches that have changed the paradigm of PDT and provided solutions to some key problems.

The transformation of CO₂ into fuels and chemicals by photocatalysis with sunlight is a promising strategy to provide a long-term solution to mitigating global warming and energy-supply problems. Several two-dimensional materials have recently been designed for the photocatalytic reduction of CO₂. This Review summarizes the state-of-the-art of such 2D photocatalysts, with special attention paid to the development of improved materials.

Next-generation metallodrugs: This Review aims to critically evaluate the potential of polyoxometalates, especially organically functionalized hybrid and nanocomposite structures, as future clinically applied metallodrugs in the combat against cancer.

Nanoparticle-mediated immunogenic cell death directly kills cancer cells and induces antitumor immune responses. Such in situ vaccination strategies can be used to activate the tumor microenvironment to synergize with cancer immunotherapies to improve patient response rates and treatment outcomes.

CO₂ can do: Electroreduction of CO₂ is an important CO₂ conversion route because of its high environmental compatibility and good combination with other renewable energy sources. Nanostructured materials exhibit outstanding performances for heterogeneous electrocatalytic CO₂ reduction. This Review describes recent advances for these nanostructured heterogeneous catalysts.

Grown from seed: Metal nanocrystals are essential to many applications in science and technology. Of all the synthetic procedures, seed-mediated growth offers unrivalled control to produce colloidal metal nanocrystals with well-defined sizes, shapes, structures, and compositions.

Doping control: Doping semiconductor nanocrystals combines properties of both the dopant ion and the quantum confinement effect of the nanocrystal. This Review presents recent advances in synthesis, luminescence, photocatalysis, photovoltaic, plasmonic, magnetic, and magneto-optic properties of doped semiconductor nanocrystals.

DNA triplex structures are stabilized by Watson–Crick and Hoogsteen/reverse Hoogsteen interstrand interactions. This Review summarizes recently reported DNA-triplex-based systems and their application as switches, sensors, and for controlled drug delivery. In addition, the implementation of DNA triplex structures for the design of stimuli-responsive materials is presented.

Make something big! The controlled destabilization of colloidal nanoparticles and the resulting assembly into macroscopic 3D structures enables the fusion of the nano and the macro worlds. Nanoparticles can be used like a toolbox to create materials with designed properties. This Review summarizes this exciting area of modern nanotechnology.