A novel low-cost aluminum–graphite dual-ion battery is reported. The battery shows a reversible capacity of ≈100 mAh g⁻¹ and a capacity retention of 88% after 200 charge–discharge cycles. A packaged aluminum–graphite battery is estimated to deliver an energy density of ≈150 Wh kg⁻¹ at a power density of ≈1200 W kg⁻¹, which is ≈50% higher than most commercial lithium ion batteries.

Batteries and supercapacitors as electrochemical energy storage and conversion devices are continuously serving for human life. The electrochemical performance of batteries and supercapacitors depends in large part on the active materials in electrodes. As an important family, Mn-based oxides have shown versatile applications in primary batteries, secondary batteries, metal–air batteries, and pseudocapacitors due to their high activity, high abundance, low price, and environmental friendliness. In order to meet future market demand, it is essential and urgent to make further improvements in energy and power densities of Mn-based electrode materials with the consideration of multiple electron reaction and low molecular weight of the active materials. Meanwhile, nanomaterials are favourable to achieve high performance by means of shortening the ionic diffusion length and providing large surface areas for electrode reactions. This article reviews the recent efforts made to apply nanostructured Mn-based oxides for batteries and pseudocapacitors. The influence of structure, morphology, and composition on electrochemical performance has been systematically summarized. Compared to bulk materials and notable metal catalysts, nanostructured Mn-based oxides can promote the thermodynamics and kinetics of the electrochemical reactions occurring at the solid–liquid or the solid–liquid–gas interface. In particular, nanostructured Mn-based oxides such as one-dimensional MnO₂ nanostructures, MnO₂–conductive matrix nanocomposites, concentration-gradient structured layered Li-rich Mn-based oxides, porous LiNi_0.5Mn_1.5O₄ nanorods, core–shell structured LiMnSiO₄@C nanocomposites, spinel-type Co–Mn–O nanoparticles, and perovskite-type CaMnO₃ with micro–nano structures all display superior electrochemical performance. This review should shed light on the sustainable development of advanced batteries and pseudocapacitors with nanostructured Mn-based oxides.

Twisted bismuth nanowire (BiNW) with abundant crystal lattice dislocations is a highly active electrocatalyst for CO ₂ reduction to formate at low overpotential.

Heteroaromatics lured into cycloadditions: The Diels-Alder reaction is widely used to produce six-membered carbon rings from alkenes and dienes. Heteroaromatics such as quinolines resemble dienes in principle, but in practice their pairs of double bonds are inert toward cycloadditions because of aromatic stabilization. Ma et al. report that by using an iridium photosensitizer, they could excite quinolines and related azaarenes to triplet states, thereby disrupting the aromaticity and enabling intermolecular, Diels-Alder–like reactivity toward alkenes (see the Perspective by Schmidt). The reactions proceeded exclusively at the flanking carbons outside the nitrogen-containing ring. Science , this issue p. 1338 ; see also p. 1313