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Downsizing into the strong confinement regime can improve single-photon purity in quantum dot emitters, but often at the expense of optical stability. Here, the authors present an alternative approach leveraging electron–phonon coupling to achieve stable, room-temperature single-photon emission with enhanced purity in colloidal hybrid lead halide perovskite quantum dots.

Solid-state X-ray detectors have enabled real-time diagnostics as well as reduced patient dose. Now researchers have shown that potentially inexpensive perovskites can be used for efficient X-ray imaging.

Narrow emission is desired for light-emitting devices. Here, Kovalenko et al. demonstrate that the emission line-broadening in perovskite quantum dots is dominated by the coupling between excitons and surface phonon modes which can be controlled by minimal surface modifications.

Time-resolved measurements show that coupling between electrons and phonons in lead halide perovskites can mediate attractive interactions between excitons, although the interaction strength depends on the specific material.

Colloidal perovskite quantum dots hold promise for polaritonic devices with strong excitonic confinement. Here the authors report the observation of room-temperature cavity exciton-polariton condensation in a perovskite-based quantum dot solid, opening the door towards quantum and photonics applications.

A colour sensor array based on multilayer monolithically stacked lead halide perovskite thin-film photodetectors achieves higher quantum efficiency and superior colour accuracy compared to conventional filter-based image sensors.

Greatly enhanced light absorption is reported in large perovskite quantum dots by realizing a transition with a giant oscillator strength at the optical bandgap.

Near-infrared imaging with solution-processed organic–inorganic hybrid photodiodes is demonstrated for the first time. The hybrid bulk-heterojunction photodiodes contain PbS nanocrystalline quantum dots as sensitizers for the detection of light of up to 1.8 µm in wavelength, have a minimum lifetime of one year, and external quantum efficiencies of up to 51%.

Cheap and sensitive gamma-ray detectors are desired for defence, medical and research applications. Solid-state gamma-radiation detectors made from solution-grown perovskites have now been demonstrated for multiple practical applications.

Arrays of cadmium selenide nanocrystals capped with molecular metal chalcogenide complexes exhibit high values of electron mobility and photoconductivity.

Optically stimulated vibrational control for materials has the potential to improve the performance of optoelectronic devices. The vibrational control of FAPbBr₃ perovskite solar cells has been demonstrated, where the fast dynamics of coupling between cations and inorganic sublattice may suppress non-radiative recombinations in perovskites, leading to reduced voltage losses.

A direct lead-halide perovskite CT imager has been demonstrated. The detector arrays have 980 μm absorber thickness and exhibit detection quantum efficiency of 80% and noise-equivalent dose of 153 pGy_air.

By comparing CsSrBr3 and CsPbBr3 with close structural similarity but the latter lacking lone-pair electrons on the octahedral metal, the authors reveal the similar vibrational anharmonicities in the two perovskites, which disentangles the electronic properties and vibrational anharmonicities.

Magnesium-sodium dual-ion batteries are promising for energy storage but their utility is limited by low oxidative stability of dual-ion electrolytes. Here, the authors demonstrate an oxidatively stable sodium-ion electrolyte and a sodium-ion conductive β-alumina membrane on the cathode side of the battery.

Excitonic single-photon superradiance is reported in individual perovskite quantum dots with a sub-100 ps radiative decay time, almost as short as the reported exciton coherence time.

Here we report an inexpensive, solution-phase growth of cm-scale single crystals of variable composition Cs_xFA_1−xPbI_3−yBr_y (FA=formamidinium, x=0–0.1, y=0–0.6), which exhibit improved phase stability compared to the parent α-FAPbI₃ compound. High-carrier mobility–lifetime product of up to 1.2 × 10⁻¹ cm² V⁻¹ and a low dark carrier density, combined with the high absorptivity of high-energy photons by Pb and I, allow the sensitive detection of gamma radiation. With stable operation up to 30 V, these novel perovskite materials have been used in a prototype of a gamma-counting dosimeter.

Solution-grown single crystals (SCs) of semiconducting methylammonium lead halide perovskites are promising materials for full-colour imaging. Here we show one-pixel photodetector prototype, constructed by stacking three layers of blue-, green- and red-sensitive MAPbCl₃, MAPbBr₃ and MAPb(Br/I)₃ crystals, respectively. This layered structure concept has several advantages: imparting a two- to three-fold reduction in the number of required pixels, three times more efficient light utilization (and thus higher sensitivity) than common Bayer filters scheme, colour moiré suppression and no need for de-mosaic image processing. In addition, the direct band gap structure of perovskites results in optical absorption that is several orders of magnitude greater than silicon.

Phospholipids enhance the structural and colloidal integrity of hybrid organic–inorganic lead halide perovskites and lead-free metal halide nanocrystals, which then exhibit enhanced robustness and optical properties.

Lithium-free graphite dual-ion battery offers a new means of energy storage. Here the authors show such device utilizing a highly concentrated electrolyte solution of KFSI in alkyl carbonates that exhibits a high energy density and high energy efficiency as well as an average discharge voltage of 4.7 V.

The high polarity of colloidal inorganic-ligand-functionalized nanocrystals can be problematic for their processing, limiting their optoelectronic applications. Here, by complexation with macrocycles, the authors enabled broad amphiphilicity of such nanocrystals and processing from a variety of solvents.

Nanomaterials provide a route to efficient solid-state conversion between thermal and electrical energy. Here, the authors demonstrate that a combination of metal and semiconductor colloidal nanocrystals can produce thermoelectric nanocomposites with high performance.

Lead halide perovskite colloidal nanocrystals have promising optoelectronic properties, such as high photoluminescence quantum yields and narrow emission linewidths. Here, the authors report low-threshold amplified spontaneous emission and two kinds of lasing in nanostructured caesium lead halide perovskites.

A Fourier-transform waveguide spectrometer is demonstrated by using HgTe-quantum-dot-based photoconductors with a spectral response up to a wavelength of 2 μm. The spectral resolution is 50 cm^–1. The total active spectrometer volume is below 100 μm × 100 μm × 100 μm.

Knowledge of fundamental properties of lead halide perovskites is crucial for their technological development. Here, authors perform magneto-optical spectroscopy, develop universal scaling laws and offer a predictive picture for interaction energies within photo-generated charge-carrier complexes.

Existing memristors cannot be reconfigured to meet the diverse switching requirements of various computing frameworks, limiting their universality. Here, the authors present a nanocrystal memristor that can be reconfigured on-demand to address these limitations

Through precise structural engineering, perovskite nanocrystals are co-assembled with other nanocrystal materials to form a range of binary and ternary perovskite-type superlattices that exhibit superfluorescence.

Designing effective covert security features is highly regarded to deter counterfeit of goods and currency in the global markets. Here, the authors present an electrohydrodynamically printed unicolour multifluorescent-lifetime security tag system based on perovskite to provide an alternative yet affordable solution.

Ensemble-level experimental evidence of exciton fine-structure splitting in perovskite quantum dots has been demonstrated, correlated to the intrinsic symmetry of these nanocrystals.

Despite remarkable optical properties in lead halide perovskites, spin control in these materials is largely unexplored. Herein Belykh et al. study the coherent spin dynamics of electrons and holes in cesium lead bromide perovskites, and evidence interaction of electron and lattice nuclear spins.

The optical and electronic properties of cesium lead halide perovskite nanocrystals are dictated by the band-edge exciton, whose physics is not elucidated. Here, the authors unveil its fine structure and demonstrate that the ground dark singlet state promotes the creation of biexcitons at low temperatures and thus correlated photon pairs.

Low-dimensional tin-halide perovskites exhibit strong temperature dependence of luminescence decay time that translates into high sensitivity over a wide range of temperatures and as such can be used in high-resolution remote thermography.

Magneto-optical spectroscopy shows that the dark exciton state in single formamidinium lead bromide perovskite nanocrystals is located below the bright exciton triplet. Slow bright-to-dark relaxation explains the intense brightness of the nanoparticles.

We show perovskite X-ray detection at zero-voltage bias with operational device stability exceeding one year. Detection efficiency of 88% and noise-equivalent dose of 90 pGyair are obtained with 18 keV X-rays, allowing single-photon-sensitive, low-dose and energy-resolved X-ray imaging.

X-ray scattering and density functional theory calculations reveal that ligand-induced tensile stress can distort the rock-salt structure of small PbS and PbSe colloidal quantum dots, creating a Pb-deficient core surrounded by a Pb-enriched shell.

Here, the authors perform spectroscopic investigations of individual Formamidinium lead iodide nanocrystals, demonstrate single-photon emission and unravel the mechanisms of carrier–phonon interactions. These results will guide the development of next-generation devices for photovoltaics and quantum technologies.

Research on the Li₇La₃Zr₂O₁₂ (LLZO)/Li interface is essential for improving the performance of LLZO-based solid-state batteries. In this comment, the authors present an analysis of the key interfacial phenomena at the LLZO/Li interface, highlighting recent developments and unresolved issues.

The halide perovskite family has, arguably, become today’s most promising emerging materials sets for optoelectronic applications. Here, we discuss the underperformance to date of the colloidal nanocrystal forms of these materials when employed in electroluminescent lighting devices relative to their counterparts, in which the emitter layer is in the form of polycrystalline films. However, we highlight the bright future of halide perovskite colloidal nanocrystals in light-emission technologies such as LCD displays, quantum light sources and even alternative LED configurations, as well as key guidelines for their further development to get there.

Although research into colloidal quantum dots has led to promising results for the realization of photovoltaic devices, a better understanding of the robustness and stability of these devices is necessary before commercial competiveness can be claimed.

Cooperative quantum effects in superlattices of quantum dots made of caesium lead halide perovskite give rise to superfluorescence, with the individual emitters interacting coherently to give intense bursts of light.

The lowest-energy exciton state in caesium lead halide perovskite nanocrystals is shown to be a bright triplet state, contrary to expectations that lowest-energy excitons should always be dark.

Coulometric titration time analysis (CTTA) has recently been introduced as a quantitative electrochemical technique to assess the compatibility of Li-ion electrolytes with metallic lithium. Here, the authors outline that the applied stack pressure is a critical factor in influencing CTTA results, highlighting the need for careful stack pressure assessment to perform conclusive CTTA experiments.

Lead-halide perovskites have entered the family of colloidal nanocrystals, showing excellent optical properties and easy synthesizability. This Review provides an insight into their chemical versatility, stability challenges and use in optoelectronics.

Bismuth fluoride is a promising cathode material for lithium ion batteries due to its high theoretical capacity and cycling stability, but low-cost production methods are needed for potential commercialization. Here, the authors report a synthetic method to grow pure BiF₃ via thermal decomposition of bismuth trifluoroacetate.