Volume 19 Issue 11, November 2020

Meteoritic diamonds and synthesized diamond-related materials contain a wide variety of complex nanostructures. This Comment highlights and classifies this structural complexity by a systematic hierarchical approach, and discusses the perspectives on nanostructure and properties engineering of diamond-related materials.

The generation of charge-neutral anti-Frenkel defects in a complex transition metal oxide provides a useful pathway for controlling electronic conductivity while minimizing the impact on existing functions.

In situ metabolic labelling and targeted modulation of dendritic cells has been achieved using a hydrogel system in combination with covalent capture of antigens and adjuvants, facilitating improved tumour-specific immune response.

The integration of silicon-based waveguides with barium titanate thin films enables the realization of efficient electro-optic switches and modulators operating at cryogenic temperatures, offering promising opportunities for quantum technologies.

The discovery of intrinsic quantum confinement effects in the form of oscillations in the optical absorption of formamidinium lead triiodide thin films is a vivid example of the surprising physical properties of these hybrid organic–inorganic materials.

Although low-temperature water electrolysers are crucial for decarbonizing the industrial sector, substantial improvements in performance and deployment rates are needed. Recent developments in devices with modified architectures and designs, and practical challenges hampering large-scale deployment are discussed.

Electrochemical capacitors can store electrical energy harvested from intermittent sources and deliver energy quickly, but increased energy density is required for flexible and wearable electronics and larger equipment. Progress in materials and devices and key perspectives in this field are outlined.

The integration of barium titanate thin films with silicon-based waveguides enables the operation of efficient electro-optic switches and modulators at temperatures as low as 4 K, with potential applications in quantum computing and cryogenic computing technologies.

Relaxor ferroelectric polymers are a material of choice for applications such as electrostrictive actuators or electrocaloric cooling. Here, the origin of relaxor behaviour at the molecular level is investigated and found to arise from conformational disorder.

A refractory high-entropy alloy was designed with the composition chosen based on the natural-mixing characteristics among refractory elements; this alloy demonstrates good tensile ductility in the as-cast state and physicochemical stability at high temperatures.

The characteristic length scale and mechanism of the metal–insulator transition in nickelate superlattices is addressed, with implications for the design of oxide electronics.

An integrated one selector–one resistor device is realized using the volatile and non-volatile switching properties of ferroelectric domains created, respectively, at the interface and in the bulk of mesa-like LiNbO₃ domain wall memory cells.

Combining quantum effects with conductivity modulation in complex oxides requires mutually exclusive criteria, making applications difficult. Using tip-induced electrical generation of anti-Frenkel defects, conducting features in Er(Mn,Ti)O₃ are written with nanoscale precision while keeping structural integrity.

Oscillatory features in the absorption spectra of formamidinium lead triiodide perovskite thin films reveal the occurrence of intrinsic quantum confinement effects with confinement on the scale of tens of nanometres.

Deployment of proton-exchange membrane fuel cells is limited by the durability of Pt-nanoscale catalysts during cathodic oxygen reduction reactions. Dissolution processes on single crystalline and thin film surfaces are now correlated leading to the design of PtAu catalysts with suppressed dissolution.

For oxygen reduction and hydrogen oxidation reactions, proton-exchange membrane fuel cells typically rely on precious-metal-based catalysts. A p-block single-metal-site tin/nitrogen-doped carbon is shown to exhibit promising electrocatalytic and fuel cell performance.

An investigation on the electronic transitions of organic radicals allows us to identify design rules to increase the oscillator strength of these emitters and obtain efficient radical-based light-emitting diodes operating in the visible range.

Protein-based materials for soft robotics that self-heal within a second while maintaining the high strength of the damaged area are reported.

A coating made from densely packed hydroxyapatite particles in an organic matrix endows the dactyl club of mantis shrimps with high stiffness and energy damping.

Dendritic cells concentrated in vivo within a hydrogel have been metabolically tagged with azido groups to enable tracking as well as delivery of antigens, adjuvants and cytokines, thereby facilitating targeted immunomodulation.