Reviews & Analysis

Heterostructuring and mixing of disparate materials provide new degrees of freedom to control carrier mobilities and exciton binding in solution-processed semiconductors. This Review highlights recent examples of heterostructured materials and devices, and examines the future direction of the field.

Externally triggered drug delivery systems use both new and established materials that are sensitive to various stimuli. These systems provide opportunities to improve the treatment of many diseases.

Nanotheranostics are nanoscale agents with both therapeutic and diagnostic functions. Cancer nanotheranostics that can be used for characterizing individual tumours, understanding and predicting nanoparticle–tumour interactions, and tailoring nanomedicines for optimized treatment hold great potential to revolutionize drug research and development, and clinical oncology.

Nanodiagnostics is a rapidly emerging field that leverages advances in nanobiotechnology to better visualize and diagnose disease. In this Review, we provide an overview of several clinically relevant imaging modalities and discuss how nanodiagnostics are enhancing their use.

Wearable electronic devices need to be flexible and breathable, as well as show high performance. In this Review, 1D energy harvesting and storage devices — in the form of fibre-based systems — are outlined, focusing on the interfaces in typical 1D configurations.

In this Review, the interplay between materials and microfluidics is examined, with the discussion focused on how recent advances in materials fabrication have expanded the frontiers of microfluidic platforms and how the new microfluidic capabilities are, in turn, furthering materials design.

Emerging materials and methods for fabricating 3D micro- and nanostructures provide powerful capabilities of relevance across diverse areas of technology. This Review highlights the latest results and future trends associated with the most powerful methods in 3D printing, folding and assembly.

Photonic metasurfaces can be used to control the polarization, phase and amplitude of light. Nonlinear metasurfaces enable giant nonlinear optical chirality, realization of the geometric Berry phase, wavefront engineering, and optical switching and modulation, and hold potential for on-chip applications.

Atomic force microscopy (AFM)-based approaches enable the characterization and manipulation of biological and synthetic biointerfaces, including tissues, cells, membranes, proteins, nucleic acid and functional materials. In this Review, the advantages and limitations of imaging, sensing, parameterizing and designing biointerfaces using AFM techniques are discussed.

Domains and domain walls are relevant for the engineering of materials functionalities. In this Review, a new classification scheme for topological domain configurations is presented and applied to several materials, including multiferroics, ferroelectrics, transition metal dichalcogenides and magnetic superconductors.

Liquid-crystalline nanostructures can form well-organized 1D, 2D and 3D channels capable of transporting ions or electrons. In this Review, the design of liquid-crystalline phases, their self-assembled structures, and the fabrication and function of devices incorporating them are described.

High pressure offers a unique degree of freedom for the creation of new materials, leading to new superconductors, superhard materials, high-energy-density materials and exotic chemical materials with unprecedented properties. This Review discusses these materials, along with recently developed theoretical and experimental methods for materials discovery at high pressures.

This Review details recent advances in battery chemistries and systems enabled by solid electrolytes, including all-solid-state lithium-ion, lithium–air, lithium–sulfur and lithium–bromine batteries, as well as an aqueous battery concept with a mediator-ion solid electrolyte.

Hybrid organic–inorganic perovskites (HOIPs) comprise a diverse range of chemical compositions from halides and azides to formates, dicyanamides, cyanides and dicyanometallates. In this Review, advances in the synthesis, structures and properties of all HOIP subclasses are summarized and their future opportunities are discussed.

Conventional photodetectors, made of crystalline inorganic semiconductors, are limited in terms of the compactness and sensitivity they can reach. Photodetectors based on solution-processed semiconductors combine ease of processing, tailorable optoelectronic properties and good performance, and thus hold potential for next-generation light sensing.

More than twenty 2D carbides, nitrides and carbonitrides of transition metals (MXenes) have been synthesized and studied, and dozens more predicted to exist. Highly electrically conductive MXenes show promise in electrical energy storage, electromagnetic interference shielding, electrocatalysis, plasmonics and other applications.

Understanding the dynamics and architecture of the nervous system requires tools for recording and modulating the activity of billions of neurons. This Review explores the history of neural engineering and the materials innovation at the interface between neural tissue and synthetic sensors.

Highly crystalline 2D superconductors can exhibit very low sheet resistances and unusual physical properties, such as a quantum metallic state, a quantum Griffiths phase and superconductivity robust against in-plane magnetic fields. The origins of these phenomena and the materials in which they are observed are reviewed.

Discoveries of new hydride properties beyond those expected are ushering in a new era in hydride research and development. This Review covers these rapidly evolving advancements; explains their relevance to future energy storage and transmission applications; and proposes future research directions.

Recent works in boiling and condensation have achieved unprecedented performance and revealed new mechanistic insights that will aid in material design. In this Review, we focus on nanoengineered materials, with emphasis on further improving the heat-transfer performance and long-term robustness.