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Abstract Metal oxide nanostructures with single-atomic heteroatom incorporation are of interest for many applications. However, a universal and scalable synthesis approach with high heteroatom concentrations represents a formidable challenge, primarily due to the pronounced structural disparities between Mhetero–O and Msub–O units. Here, focusing on TiO2 as the exemplified substrate, we present a diethylene glycol-assisted synthetic platform tailored for the controlled preparation of a library of M1-TiO2 nanostructures, encompassing 15 distinct unary M1-TiO2 nanostructures, along with two types of binary and ternary composites. Our approach capitalizes on the unique properties of diethylene glycol, affording precise kinetic control by passivating the hydrolytic activity of heteroatom and simultaneously achieving thermodynamic control by introducing short-range order structures to dissipate the free energy associated with heteroatom incorporation. The M1-TiO2 nanostructures, characterized by distinctive and abundant M–O–Ti units on the surface, exhibit high efficiency in photochromic photothermal catalysis toward recycling waste polyesters. This universal synthetic platform contributes to the preparation of materials with broad applicability and significance across catalysis, energy conversion, and biomedicine.

Abstract Motivated by the high-performance solid-state lithium batteries enabled by lithium superionic conductors, sodium superionic conductor materials have great potential to empower sodium batteries with high energy, low cost, and sustainability. A critical challenge lies in designing and discovering sodium superionic conductors with high ionic conductivities to enable the development of solid-state sodium batteries. Here, by studying the structures and diffusion mechanisms of Li-ion versus Na-ion conducting solids, we reveal the structural feature of face-sharing high-coordination sites for fast sodium-ion conductors. By applying this feature as a design principle, we discover a number of Na-ion conductors in oxides, sulfides, and halides. Notably, we discover a chloride-based family of Na-ion conductors NaxMyCl6 (M = La–Sm) with UCl3-type structure and experimentally validate with the highest reported ionic conductivity. Our findings not only pave the way for the future development of sodium-ion conductors for sodium batteries, but also consolidate design principles of fast ion-conducting materials for a variety of energy applications.

Abstract Solid electrolyte is vital to ensure all-solid-state batteries with improved safety, long cyclability, and feasibility at different temperatures. Herein, we report a new family of amorphous solid electrolytes, xLi2O-MCly (M = Ta or Hf, 0.8 ≤ x ≤ 2, y = 5 or 4). xLi2O-MCly amorphous solid electrolytes can achieve desirable ionic conductivities up to 6.6 × 10−3 S cm−1 at 25 °C, which is one of the highest values among all the reported amorphous solid electrolytes and comparable to those of the popular crystalline ones. The mixed-anion structural models of xLi2O-MCly amorphous SEs are well established and correlated to the ionic conductivities. It is found that the oxygen-jointed anion networks with abundant terminal chlorines in xLi2O-MCly amorphous solid electrolytes play an important role for the fast Li-ion conduction. More importantly, all-solid-state batteries using the amorphous solid electrolytes show excellent electrochemical performance at both 25 °C and −10 °C. Long cycle life (more than 2400 times of charging and discharging) can be achieved for all-solid-state batteries using the xLi2O-TaCl5 amorphous solid electrolyte at 400 mA g−1, demonstrating vast application prospects of the oxychloride amorphous solid electrolytes.

Layered oxide cathode active materials suffer from interfacial structural instability when coupled with sulfide solid-state electrolytes. Here, the authors propose a gradient coating with a lithium oxythiophosphate layer that can stabilize the cathode|solid-state electrolyte interface.

Catalytic hydrogenolysis of end-of-life polyolefins can produce value-added liquid fuels and therefore holds great promises in plastic waste reuse and environmental remediation. The major challenge limiting the recycling economic benefit is the severe methanation (usually >20%) induced by terminal C–C cleavage and fragmentation in polyolefin chains. Here, we overcome this challenge by demonstrating that Ru single-atom catalyst can effectively suppress methanation by inhibiting terminal C–C cleavage and preventing chain fragmentation that typically occurs on multi-Ru sites. The Ru single-atom catalyst supported on CeO2 shows an ultralow CH4 yield of 2.2% and a liquid fuel yield of over 94.5% with a production rate of 314.93 gfuels gRu−1 h−1 at 250 °C for 6 h. Such remarkable catalytic activity and selectivity of Ru single-atom catalyst in polyolefin hydrogenolysis offer immense opportunities for plastic upcycling.

Synthesizing single-atom catalysts through a general method presents a great challenge. Here the authors report that Fe, Co and Ni single-atom catalysts can be obtained using pre-located isolated Pt atoms as the catalyst and identify the role of Pt single atoms in the synthesis process.

We report a study on the effect of chemical and electrochemical cleaning of tarnished daguerreotypes observed using X-ray fluorescence (XRF) microscopy with a micro-focussed X-ray beam from a synchrotron source. It has been found that, while both techniques result in some success depending on the condition of the plate and the experimental parameters (chemical concentration, voltage, current, etc.) the effect varies, and cleaning is often incomplete. The XRF images using Hg Lα,β at an excitation energy just above the L3 edge threshold produce fine images, regardless of the treatment. This finding confirms previous observations that if the bulk of the image particles remains intact, the surface tarnish has little effect on the quality of the original daguerreotype image retrievable from XRF.

Abstract Experimental detection of the Pt 5d densities of states in the valence band is conducted on a series of Pt-Ni alloys by high energy resolution valence-to-core X-ray emission spectroscopy (VTC-XES) at the Pt L3-edge. VTC-XES measurements reveal that the Pt d-band centroid shifts away from the Fermi level upon dilution, accompanied by concentration-dependent Pt d-band width. The competition between the strain effect and ligand effect is observed experimentally for the first time. It is found that the d-band widths in Pt3Ni and PtNi are broader than that of Pt metal due to compressive strain which overcompensates the effect of dilution, while it is narrower in PtNi3 where the ligand effect dominates. VTC-XES is demonstrated to be a powerful tool to study the Pt d-band contribution to the valence band of Pt-based bimetallic. The implication for the enhanced activity of Pt-Ni catalysts in oxygen reduction reaction is discussed.

Electrochemical CO2 reduction to the valuable n-propanol is challenging due to the complicated C3 forming mechanism. Here, authors demonstrate double sulfur vacancies formed on hexagonal copper sulfide can serve as efficient electrocatalytic centers.

The origin of Dzi beads, also called “tian zhu”, has always been a mystery. These beads come in a variety of patterns, shapes and sizes. They have cultural and heritage significance in Tibet and areas surrounding the Himalayas. The most recognized beads are those with the “eye” pattern. They are said to ward off evil spirits. Due to their reputation, the demand for Dzi beads has increased in Asia. Herein, we report a study of a Dzi bead with a three-eye pattern using X-ray diffraction (XRD), X-ray fluorescence (XRF), X-ray absorption near edge structure (XANES) and imaging techniques. This is a novel area for Dzi bead research using X-rays from a synchrotron light source to determine the chemical composition of the bead, if the pattern is natural or man-made or if the bead is genuine or a replica. These techniques revealed the bead to be composed of agate (silicon dioxide). An interesting feature on the bead’s surface was the etched rings, which were observed to contain regular copper hot spots on their circumference. Our results suggest that the Dzi bead was genuine and started out as an earth-formed agate, with the pattern crafted.

The electrocatalytic upgrading of CO to higher-value fuels provides a promising route to multi-carbon alcohol products. Here, the authors show that high alcohol selectivity and activity can be achieved by incorporating palladium in copper.

The electro-oxidative synthesis of valued chemicals offers to enhance the overall efficiency and economic viability of renewable electrosynthesis systems. Here, the authors use dopant-tuned catalysts to promote the electrosynthesis of dimethyl carbonate from CO and methanol via oxidative carbonylation.

Atomically precise control over elemental distributions presents a challenge in the preparation of catalytic nanomaterials. Here the authors report Pt-Ru bimetallic dimer structures through atomic layer deposition process and identify the roles of Pt and Ru in hydrogen evolution reaction.

The first commercially viable photographic image, the daguerreotype, captured images for a span of approximately 20 years (1839⁻1860). DeDterioration now disfigures many of these valuable images. One proposed restoration method is an electrochemical process. However, its safety and effectiveness are still under debate within the conservation community as the effects of this treatment, and its physical and chemical impact on the daguerreotype image, have not yet been analyzed in depth. This study used synchrotron-based micro-X-ray fluorescence to map the elemental distribution pre- and post-electrocleaning on 19th century daguerreotypes using both soft and hard incident X-rays. X-ray absorption spectroscopy was used to probe local chemistry before and after cleaning. Two different electro-treatment methods were compared: the original method proposed by Barger and a second put forward by Wei. When used correctly, both processes significantly reduced the S and Cl surface contamination without dulling the surface. However, both electrochemical methods used in this study resulted in a loss of Hg and Au from the surface. In all cases, the Hg distribution tracks with image particle density allowing the retrieval of full portraits from entirely corroded daguerreotypes, suggesting that Hg concentration may be a useful proxy for the original image.

Controlled synthesis of Mn-doped ZnO nanostructures with Mn concentrations of 1%, 3%, and 10% at. has been carried out using sol–gel methods and temperature treatments at 400, 600, and 800 °C. It is found that Mn is successfully introduced into the hcp oxide lattice of ZnO nanoparticles of a range of sizes from a few nm to 102 nm, depending on temperature conditions. It is also found that a secondary phase appears as the Mn concentration and processing temperature increase, most probably in the form appropriately described as MnOx clusters on the surface, although the dominant component remains hcp ZnO. The x-ray absorption near edge structure at all edges of interest reveals that the Mn2+ ion substitutes Zn2+ at the tetrahedral site and that the secondary phase exhibits a clear signature of the octahedral local environment at the Mn L3,2 and O K-edge. X-ray excited optical luminescence excited at 1085 eV (just above the Zn L3,2 edge) shows that the characteristic bandgap emission is slightly blue shifted and the luminescence from both the bandgap and defect emission is quenched somewhat with the latter significantly shifted to longer wavelengths in the region observed for surface and near surface defects. The Mn-doped samples processed at low temperature are poor light emitters due to the high degree of disorder and improve markedly with annealing at higher temperature. The magnetic properties of these systems were also investigated. The results suggest that Mn doping impedes radiative recombination, which is in favor of improved photocatalytic behavior. The implication of these findings is discussed.

Upgrading wasted carbon emissions to high-value, multi-carbon products provides an economic route to reduce carbon dioxide levels, but such conversions have proven challenging. Here, authors explore copper adparticles as highly active surfaces that convert CO to n-propanol with high selectivities.

Carbonate-based electrolytes can impart advantages in lithium sulfur batteries, but performance is often limited by incompatibility with sulfur-based cathodes. Here the authors elucidate a mechanism for conversion of sulfur to lithium sulfide and demonstrate improved performance in a Li-S cell.

Coating the active materials of interest with carbon is a widely employed way to boost the performance of lithium ion batteries. Here the authors show the formation of a conductive phase on LiFePO4 during carbon coating, which is size, annealing temperature and reduction atmosphere dependent.

Downsizing platinum based nanocatalysts has the twin advantages of lower platinum usage and increased activity per platinum atom. Here, the authors report an atomic layer deposition technique for single platinum atom catalyst fabrication and assess their hydrogen evolution activity.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Tip-enhanced Raman spectroscopy (TERS) is used to investigate the influence of strains in isolated and overlapping silicon nanowires prepared by chemical etching of a (100) silicon wafer. An atomic force microscopy tip made of nanocrystalline diamond coated with a thin layer of silver is used in conjunction with an excitation wavelength of 532 nm in order to probe the first order optical phonon mode of the [100] silicon nanowires. The frequency shift and the broadening of the silicon first order phonon are analyzed and compared to the topographical measurements for distinct configuration of nanowires that are disposed in straight, bent or overlapping configuration over a microscope coverslip. The TERS spatial resolution is close to the topography provided by the nanocrystalline diamond tip and subtle spectral changes are observed for different nanowire configurations.