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Granular metals (GMs), consisting of metal nanoparticles separated by an insulating matrix, frequently serve as a platform for fundamental electron transport studies. However, few technologically mature devices incorporating GMs have been realized, in large part because intrinsic defects (e.g., electron trapping sites and metal/insulator interfacial defects) frequently impede electron transport, particularly in GMs that do not contain noble metals. Here, we demonstrate that such defects can be minimized in molybdenum–silicon nitride (Mo–SiNx) GMs via optimization of the sputter deposition atmosphere. For Mo–SiNx GMs deposited in a mixed Ar/N2 environment, x-ray photoemission spectroscopy shows a 40%–60% reduction of interfacial Mo-silicide defects compared to Mo–SiNx GMs sputtered in a pure Ar environment. Electron transport measurements confirm the reduced defect density; the dc conductivity improved (decreased) by 104–105 and the activation energy for variable-range hopping increased 10×. Since GMs are disordered materials, the GM nanostructure should, theoretically, support a universal power law (UPL) response; in practice, that response is generally overwhelmed by resistive (defective) transport. Here, the defect-minimized Mo–SiNx GMs display a superlinear UPL response, which we quantify as the ratio of the conductivity at 1 MHz to that at dc, Δ σ ω. Remarkably, these GMs display a Δ σ ω up to 107, a three-orders-of-magnitude improved response than previously reported for GMs. By enabling high-performance electric transport with a non-noble metal GM, this work represents an important step toward both new fundamental UPL research and scalable, mature GM device applications. [ABSTRACT FROM AUTHOR]

It is a novel-effective process for realizing high-efficiency sensing and continuous gas monitoring by introducing precious metals into metal–oxide–semiconductors (MOSs). In this study, Ag is exploited to prepare surface functionalized SnO2 nanoparticles (NPs) and innovative xAg@SnO2/CsPbBr3, activating and catalyzing the gas sensing reactions on semiconductors. The results show that the precious metal Ag NPs promote the directional transport of carriers, thus improving the gas sensing performances. In addition, innovative xAg@SnO2/CsPbBr3 composites originated from Ag@SnO2 NPs and 3-mercaptopropionic acid treated all-inorganic perovskite CsPbBr3 are constructed to further accelerate electron transfer on heterointerfaces, enabling continuous and efficient monitoring of ethanolamine (EA) at room temperature. The sensing properties of Ag@SnO2/CsPbBr3 on various volatile organic compounds are investigated. Compared with pure CsPbBr3, the EA response of as-prepared 2Ag@SnO2/CsPbBr3 is obviously improved by about sevenfold. The response/recovery time is greatly shortened, besides the good stability. Another interesting result for xAg@SnO2/CsPbBr3 is the lower limit of detection of 44.43 ppb. The work demonstrates that Ag modification facilitates the adsorption/desorption rate and the response. Furthermore, the catalytic activation of noble metal Ag NPs and the synergistic interaction of SnO2/CsPbBr3 nano-heterojunctions promote EA sensing performances at room temperature. [ABSTRACT FROM AUTHOR]

Reliable nanoswitch operation requires low contact voltages and stable electrical contact resistance (E C R). Surface cleanliness is crucial to prevent nanomechanical switch failure, which can occur due to the presence of insulating adventitious hydrocarbon films. In situ O2 plasma cleaning is effective but oxidizes metal surfaces. Here, the noble metal Pt, which forms PtOx, is employed to form electrodes. Previous studies report on PtOx electrical resistivity, but the effects of PtOx evolution at contacting interfaces due to electrical and mechanical stimuli have not been explored. This study investigates the impact of PtOx on E C R at low contact voltages under hot switching, cold switching, and mechanical cycling conditions. An increase in E C R upon plasma cleaning indicates the presence of a resistive PtOx layer. After hot and cold switch cycling at applied voltages of 300 mV or less, a low stable E C R is achieved. A higher contact voltage accelerates E C R stabilization. The results are consistent with PtOx film volatilization, which is primarily due to Joule heating rather than mechanical rupture. This investigation advances the understanding of interface evolution in plasma-cleaned nanoswitches. [ABSTRACT FROM AUTHOR]

Body-centered-cubic–face-centered-cubic (bcc–fcc) multi-metallic nanoparticles (NPs) associating a single-crystal core (Fe, FeCo alloys, etc.) with a polycrystalline noble metal shell (Au, AuAg alloys, etc.) are perfectly symmetrical or more irregular, even dramatically dissymmetrical, yet presenting a good crystalline organization. Here, a combination of experimental analysis and theoretical symmetry analysis is proposed, in order to provide a unified description of the observed morphologies (Fe–Au and Fe–AuAg systems), whatever their symmetry, and predict some morphology variability in a population of NPs. First, the central role of the crystal lattice accommodation is comprehensively analyzed from the experimental Fe–AuAg system. The two possible bcc–fcc epitaxial relationships generate a core–shell interface in the shape of a truncated rhombic dodecahedron. This results in two different types of grains in the shell, which are elastically accommodated between them by an equal distribution of twins and low-angle grain boundaries, however, at the cost of internal stresses. At the same time, symmetry breaking results from two possible growth variants originating from the Nishiyama–Wasserman epitaxial relationships. The shell grains fit together in a nanopuzzle-like organization, resulting in a large number of possible arrangements distributed in 13 different point groups of symmetry, all of lower order than the core symmetry (highest order of cubic symmetry). If the variants are randomly distributed, the probability for the NP to be asymmetric (group 1) is 80%. The dissymmetrical development of the NPs is then discussed. Extending this approach to other core shapes succeeds in predicting dissymmetrical or dramatically off-centered morphologies experimentally observed in Fe–Au NPs. [ABSTRACT FROM AUTHOR]

Ultrafast luminescence in Mg was investigated in the infrared region, between 0.35 and 1.05 eV, and compared with the results for Al, using a luminescence upconversion technique. The luminescence intensity of these metals at 0.9 eV was higher than that of platinum with a similar surface roughness under the same excitation density. Although the Mg and Al are adjacent to each other in the periodic table and belong to "light metals," having similar band structures, their luminescence spectra differ significantly. Pronounced peak structures were found for Mg and these were attributed to interband transitions within the conduction bands consisting of 3s and 3p orbitals overlapped on the intraband continuum, based on density functional theory band structure calculation. This result is in contrast to the interband luminescence in noble metals (Au, Ag, and Cu) under continuous-wave blue laser excitation, where the final states have been assigned to the d bands. A comparison of the spectra of rough and specular surfaces suggested that the surface roughness is not essential for mitigating wavenumber mismatch for intraband transitions. The luminescence from light metals, which are harmless to humans, will be attractive for biomedical applications. [ABSTRACT FROM AUTHOR]

Surface property modification of catalyst support is a straightforward approach to optimize the performance of supported noble metal catalysts. In particular, oxygen vacancies and hydroxyl groups play significant roles in promoting noble metal dispersion on catalysts as well as catalytic stability. In this study, we developed a nanoflower-like TiO2-supported Pd catalyst that has a higher concentration of oxygen vacancies and surface hydroxyl groups compared to that of commercial anatase and P25 support. Notably, due to the distinctive structure of the nanoflower-like TiO2, our catalyst exhibited improved dispersion and stabilization of Pd species and the formation of abundant reactive oxygen species, thereby facilitating the activation of CO and O2 molecules. As a result, the catalyst showed remarkable efficiency in catalyzing the low-temperature CO oxidation reaction with a complete CO conversion at 80 °C and stability for over 100 h. [ABSTRACT FROM AUTHOR]

Atomic isolated and dispersed single atom catalyst is ideal for high-performance industrial catalyst. However, the contribution from small amounts of nanoclusters coexisting with single atoms to the catalytic reaction activity is often neglected. In this work, a MXene-supported uniformly dispersed Pt single atoms and nanoclusters (Pt 1 +Pt n /MXene) were obtained by self-assembly through an impregnation method. The catalyst exhibits high electrochemical performance in the hydrogen evolution reaction with an overpotential of only 61.3 mV and a Tafel slope of 32.5 mV dec−1 at a current density of 10 mA cm−2 in an acidic environment. The XAFS analysis and further DFT calculation indicate that the synergistic effect between single atoms and nanoclusters can facilitate adsorption of H* and promote the HER reaction. This work provides an efficient method for integrating multiple active sites in noble metal catalysts. • Constructing Pt sites on MXene enables a strong synergism between nanoclusters and single atoms. • Pt 1 +Pt n /MXene possesses large numbers of highly active Ti–O–Pt interfacial sites. • Ti–O–Pt sites make Pt 1 +Pt n /MXene obtain an outstanding catalytic performance in HER. • Pt 1 +Pt n /MXene boosts the adsorption of H* and promotes the HER reaction process. [ABSTRACT FROM AUTHOR]

Ta 2 O 5 /Pd hybrid microspheres were readily synthesized via a one-step thermal solution process employing a template composed of glucose carbon spheres, yielding a structure characterized by a rough and porous surface. This morphology offers an expanded contact area and increased sites for ethanol reactions of Ta 2 O 5 /Pd hybrid microspheres. At room temperature (25 °C), the Ta 2 O 5 /Pd hybrid microspheres exhibited responsiveness to ethanol concentrations ranging from 50 to 700 ppm, displaying a linear response pattern to a narrow concentration gradient of 90–120 ppm. The hybrid exhibited notable sensitivity, manifesting a response value of 5.1–100 ppm ethanol. In addition, they displayed less responsiveness to other VOCs gases, were minimally affected by humidity, and maintained gas-sensitive stability for 30 days, demonstrating excellent selectivity and long-term stability. Based on the fitting curve analysis, the material theoretically demonstrated the ability to detect ethanol at concentrations as low as 101 ppb. Ta 2 O 5 /Pd hybrid microspheres modified by glucose carbon sphere templates and noble metal nanoparticles are promising candidates for ethanol room temperature sensing, providing new insights into the development of room temperature sensing. [ABSTRACT FROM AUTHOR]

In this work, a high density of dispersed Co9S8 nanoparticles (NPs) loaded in carbon aerogels as bi-catalysts (Co9S87.5NP/CA catalysts) were successfully prepared by virtue of the seeded-growth method that is widely used for the synthesis of noble metal NPs. It is found that the optimal molar ratio of Co2+-to-Fe3+ ions for the formation of a high density of dispersed Co9S8 NPs with average sizes of 90 nm is determined to be 7.5 (represented by the superscript number) at the fixed concentration of tannic acid (TA) ([TA] : [Fe3+] = 1 : 1). Moreover, the concentration of Fe3+ precursors is the key that can guarantee the formation of dispersed Co9S8 NPs by the overgrowth of in situ Fe SA-NCs as seeds by the spatial confinement effect during the pyrolysis. Thanks to the multiple valence states of elemental Co in the Co9S8 NPs and their good dispersity in the as-prepared Co9S87.5NP/CA catalysts, the half-wave potential (E1/2) and the overpotential at 10 mA cm−2 (η10) towards the alkaline oxygen reduction reaction (ORR) and the acidic hydrogen evolution reaction (HER) can be improved up to 0.891 V and 177 mV, respectively. [ABSTRACT FROM AUTHOR]

The commercialization of magnesia–air batteries (Mg–air) necessitates the development of highly efficient, cost-effective, and durable electrocatalysts for the oxygen reduction reaction (ORR), replacing expensive and unstable precious metal electrocatalysts. A hard template-assisted synthesis of FeCo nanoparticles immobilized on N-doped porous carbon (Fe–Co–C–N) for the ORR is reported. The half-wave potential of Fe–Co–C–N for ORR (E1/2 = 0.88 V vs. RHE) is elevated by 40 mV compared to that of 20 wt% Pt/C (E1/2 = 0.84 vs. RHE). The catalyst exhibits exceptional catalytic performance and remarkable stability. The discharge voltage of the Mg–air battery, utilizing Fe–Co–C–N as the cathode catalyst (1.29 V), surpasses that of the battery employing 20 wt% Pt/C as the cathode catalyst (1.28 V). The Mg–air battery with Fe–Co–C–N as the cathode catalyst exhibited excellent discharge stability and maintained a stable discharge for over 200 hours. The present study offers valuable insights into the structural design and regulatory mechanisms governing the performance of M–N–C catalysts in Mg–air batteries. [ABSTRACT FROM AUTHOR]

Lewis base/transition-metal cooperatively catalyzed asymmetric transformations have attracted extensive attention as they offer complementary catalytic systems within the realm of cooperative catalysis. Recently, the synergistic use of Lewis bases in combination with earth-abundant 3d metals has emerged as a fascinating prospect, presenting an opportunity to move away from the reliance on noble metals and to explore novel catalytic processes. In this Account, we highlight our recent achievements regarding the chemistry and synthetic utility of isothiourea (ITU) activated C1-ammonium enolates and N-heterocyclic carbene (NHC)-bound homoenolate equivalents in conjunction with 3d transition-metal activated electrophiles. The remarkable success in the stereoselective construction of carbon–carbon and carbon–heteroatom bonds has led to significant contributions to stereodivergent synthesis. 1 Introduction 2 ITU/Copper Cooperative Catalysis 3 NHC/Copper Cooperative Catalysis 4 NHC/Nickel Cooperative Catalysis 5 Conclusion [ABSTRACT FROM AUTHOR]

Highly sensitive strain sensors have been widely used in human motion monitoring, medical treatment, soft robots, and human–computer interaction, and the recycling of functional materials is in a huge demand for eco‐friendly and sustainable electronics. However, the manufacturing of recyclable strain sensors still remains challenging. Here, a semi‐wrapped structure based on silver nanowires and polyvinyl alcohol is proposed to realize a recyclable and stable strain sensor. It has shown excellent sensitivity, fast response, high stretchability and good environmental stability, and is successfully applied for human motion monitoring. In addition, a simple strategy is developed to effectively recycle silver nanowires in an eco‐friendly manner. The recyclable and stable strain sensor demonstrates potential applications in wearable and stretchable electronics, and the recycling strategy can be extended to other noble metal nanomaterials. [ABSTRACT FROM AUTHOR]

The reconstruction of local electronic states in Pt-O x is an effective strategy for balancing charge distribution and enhancing the intrinsic activity of noble metals. This study presents the use of highly porous and oxygen-rich activated bluecoke powders as a desirable carbon support, and regulates Pt-O x bonds by incorporating the Fe as transition metal, leading to the development of an efficient bluecoke-based electrocatalyst characterized (Fe/Pt–O@MKABC) by exceptionally low Pt loading. The loading amount of Pt in Fe/Pt–O@MKABC is only 0.98 wt%, which is less than the 5% reported for commercial Pt/C catalyst, yet its hydrogen evolution performance is comparable. The developed catalyst presents exciting catalytic ability with overpotential of only 17 mV at 10 mA/cm2, a high mass activity of 8.3 A/(cm2·mg pt) at 50 mV, a large turnover frequency of 8.29 H 2 /s, and outstanding durability with a mere increase of 5 mV over 10000 cycles in acidic electrolyte. Detailed spectroscopic analysis and theoretical calculation results demonstrate that the abundant oxygen on activated bluecoke powders provides an opportunity for the construction of Fe-O y and Pt-O x. The introduction of Fe leads to electron rearrangement in Fe/Pt–O@MKABC, promoting electron transfer and reducing the adsorption free energy of H*, and the interaction between Fe-O y and Pt-O x enhances the hydrogen evolution reaction (HER) performance. [Display omitted] • Utilizing highly porous and oxygen-rich activated bluecoke powders as defect carbon support. • The introduction of Fe optimizes the Pt-O x bonds and significantly reduces the Pt loading. • The loading amount of Pt in the developed Fe/Pt–O@MKABC electrocatalyst is only 0.98 wt%. • The interaction between Fe-O y and Pt-O x accelerates the Volmer-Heyrovsky process. [ABSTRACT FROM AUTHOR]

Carbonylation reactions have been widely used to construct carbonyl-containing molecules or carbon enhancement reactions, which are mostly catalyzed by noble metals (Pd, Rh, Ru, Ir). In this review, we introduce the copper-catalyzed carbonylation reactions that have been developed in our group. Diverse reactions have been developed using various substrates, including the carbonylation of C–H activated alkanes, the difunctionalization of unsaturated C–C bonds, and the carbonylation of alkyl halides via the radical pathway. 1 Introduction 2 Cu-Catalyzed Carbonylation of C(sp3)–H Bonds 3 Cu-Catalyzed Carbonylative Difunctionalization of Unsaturated Bonds 4 Cu–X (H or B) Mediated Acylation of Unsaturated Bonds with Electrophiles 5 Cu–X (H or B) Mediated Carbonylation of Unsaturated Bonds 6 Cu-Catalyzed Carbonylation of Alkyl Halides 7 Other Types of Copper-Catalyzed Carbonylation Reactions 8 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

Polymer electrolyte membrane fuel cells (PEMFCs) are an important enabler of the nascent hydrogen economy. However, due to the reliance on precious metal catalysts like platinum, reducing the cost and broad penetration of PEMFCs beyond vehicle application remains a challenge. In this respect, alternative non‐precious metal catalysts and other carbon‐based catalysts remain the holy grail toward advanced low‐cost PEMFC. This review summarizes recent progress along the development of non‐precious catalysts and their performance under PEMFC operation. Critical factors such as the activity, stability, and durability of non‐precious metal catalysts and their associated mechanisms including the paths leading to degradation are discussed. Ultimately, the review concludes by highlighting the impressive activity and potential of NPM catalysts and the areas of focus to enable the translation of non‐precious catalysts to commercially viable PEMFC systems. [ABSTRACT FROM AUTHOR]

Direct ethanol fuel cells (DEFCs) have been widely considered as a feasible power conversion technology for portable and mobile applications. The economic feasibility of DEFCs relies on two conditions: a notable reduction in the expensive nature of precious metal electrocatalysts and a simultaneous remarkable improvement in the anode's long-term performance. Despite the considerable progress achieved in recent decades in Pt nanoengineering to reduce its loading in catalyst ink with enhanced mass activity, attempts to tackle these problems have yet to be successful. During the ethanol oxidation reaction (EOR) at the anode surface, Pt electrocatalysts lose their electrocatalytic activity rapidly due to poisoning by surface-adsorbed reaction intermediates like CO. This phenomenon leads to a significant loss in electrocatalytic performance within a relatively short time. This review provides an overview of the mechanistic approaches during the EOR of noble metal-based anode materials. Additionally, we emphasized the significance of many essential factors that govern the EOR activity of the electrode surface. Furthermore, we provided a comprehensive examination of the challenges and potential advancements in electrocatalytic EOR. [ABSTRACT FROM AUTHOR]

Effective solid-phase extractants (SPE) based on multi-walled carbon nanotubes (CNT) of various structures modified with an organic reagent, 2-mercaptobenzothiazole, were developed. Using scanning and transmission electron microscopy, the morphological and structural features of SPE samples and their elemental composition were determined. It was shown that the specific surface area of the modified CNT is approximately two times lower compared to the original CNT. It was revealed that the modified materials are CNT coils coated with a uniform organic shell 10−15 nm thick. The sorption capacity of the original nanotubes in 1.0 M HCl and of their modified forms (in 0.1−3.0 M HCl) at room temperature and at 80°C was determined. It was found out that in strongly acidic media, SPE based on G-183 CNT and 2-mercaptobenzothiazole, effectively sorbs Pt, Pd and Au at room temperature, and Ru and Rh at the temperature of 80°C. A possibility of the selective extraction of platinum group metals and gold with this sorbent in the presence of macroquantities of Al, Fe, Cu, Ca and Mg was assessed. [ABSTRACT FROM AUTHOR]

Since the colorimetric method has the characteristics of being simple and low cost, the fluorescence spectrum has the characteristics of a strong signal, and Surface-enhanced Raman scattering (SERS) detection has the characteristics of high sensitivity and strong specificity, people usually use these three methods for detection, but the detection of a single sample takes more time. If multiple samples can be tested at the same time, the detection efficiency and sensitivity can be improved, and the selectivity and reliability will be greatly improved. Multiplex sensing also provides a new direction for researchers. To fully understand the research of multiplex sensing based on the plasmonic optics of noble metal nanostructures, this review summarizes all the results previously reported in this field. It also discusses the principles of various detection methods and the biochemical application of multiple detections and finally summarizes the challenges and prospects. [ABSTRACT FROM AUTHOR]

All-inorganic CsPbBr3 perovskite quantum dots (PQDs) are promising candidates in perovskite solar cells (PSCs) due to its excellent stability. However, the large bandgap of PQDs and expensive materials of hole transport materials (HTMs) and noble metal proposed a major obstacle to promoting the further development of PSCs. Herein, a promising method introducing MA+ into the CsPbBr3 PQDs can well decrease the bandgap. Furthermore, the stacked structure assembled by a photoanode A and black electrode B shows a promising prospect for photovoltaic application, in which the black electrode B, a carbon quantum dots, extracted from molasses was used for simultaneous replacement of metals and HTMs, and each layer employed screen-printing method to deposition in the aspect of fabrication of device. Based on this systematic optimization, the assembled PSCs achieve an enhanced PCE of 1.57%, which demonstrated an obvious improvement in comparison to the pristine device. This study demonstrates a low-cost and facile strategy for the fabrication of efficient PSCs with stacked architecture. [ABSTRACT FROM AUTHOR]

This article examines the concept of U.S. vertical power and its effects on the expansion of the United States, with a focus on underground spaces and temporalities. It specifically explores the relationship between mining, Indigenous lands, and colonial authority. The article argues that mining was not only a means of extracting minerals, but also a tactic used to violently maintain control over Native American lands. It also discusses the long-term perspectives of U.S. empire and the lasting consequences of short-term thinking. The example of Elk Mountain in Colorado is used to illustrate these arguments. The article concludes by highlighting the connection between mining and militarism, as well as the role of miners in expanding U.S. power. [Extracted from the article]

The content and distribution of precious metals in fine-grained bottom sediments, accumulated in the technogenic period (last decades) in the southwestern part of the Chukchi Sea, have been studied. The ubiquitous or local enrichment of the sediments with silver, gold, platinum, and palladium according to the average for the Earth's crust, as well as their enrichment with gold and palladium relative to pre-technogenic (Late Holocene) deposits, was shown. Differences in the conditions of the accumulation of precious metals in the Late Holocene and modern sediments were shown. Sources of input were determined, and the possibility of technogenic enrichment of the sources was proved by the methods of multicomponent statistical analysis of the total chemical composition of the sediments. [ABSTRACT FROM AUTHOR]

Iodide has long been recognized as an effective shape-directing agent for facilitating the growth of anisotropic noble metal nanostructures. However, little attention has been paid to the specific interaction between iodide and metal nanoparticles. In this study, we demonstrate the selective recognition of iodide in solution by the carbon-dot-gold nanoparticles (Cdot-AuNPs) ensemble. Irregularly-shaped AuNPs were generated through the reduction of HAuCl4 by citrate ions and stabilized by Cdot at ambient temperature. Upon the addition of iodide, the color of the solution changed from blue to red with the growth of AuNPs to semi-spherical nanoparticles, as confirmed by transmission electron microscopy. The selectivity test validated that only iodide could induce this specific visual response, highlighting a novel interaction mechanism between iodide and AuNPs. The recognition of iodide by this Cdot-AuNPs ensemble showed good resistance toward many environmentally relevant metal ions, particularly Ca2+, providing potential for the identification of iodide ions in real samples. Mixing tetrachloroauric acid, sodium citrate, and bee pollen-derived carbon dots (Cdot) at ambient temperature leads to the preparation of Cdot-AuNPs ensemble for the specific colorimetric recognition of iodide by reshaping the dimensions of the AuNPs. [ABSTRACT FROM AUTHOR]

The green synthesis of noble metal nanoparticles has gained a lot of interest in the area of nanotechnology, because of its high therapeutic properties. The present study focussed on the synthesis of the silver nanoparticles (Ag-NPs) using Ceropegia debilis leaf extract and characterized by various physio-chemical techniques and surface morphological studies. The prepared Ag-NPs exhibit a face-centred cubic structure, spherical morphology, and high purity as shown by XRD, SEM, and EDS analyses. The average size of the Ag-NPs was confirmed by TEM study as 18.6 ± 7.5 nm. The synthesized Ag-NPs show remarkable antioxidant activity of 72.1% compared to standard BHT 86.9%. Furthermore, Ag-NPs show remarkable cytotoxic properties against MCF 7 and A 549 cell line of 37.19% and 33.33%, respectively at 250 µg/mL. The antibacterial activity of Ag-NPs was investigated against the human pathogen and intestinal pathogen Staphylococcus aureus and Escherichia coli by agar disc diffusion method. Moreover, the synthesised Ag-NPs exhibit good antifungal properties against the fungal specimen Trichoderma viride assessed by well diffusion technique. In addition, Ag-NPs serve as an excellent nanocatalyst in the removal of toxic methylene blue dye (93.2%) from industrial wastewater under sunlight irradiation. [Display omitted] • Silver nanoparticles were synthesized by Ceropegia debilis extract. • SEM and TEM used for surface morphology and size determination. • Impressive anti-proliferative activity towards MCF 7 and A 549 were observed. • Effective nanocatalyst for the degradation of methylene blue dye. [ABSTRACT FROM AUTHOR]

Intermediate sulfidation epithermal deposits represent significant reservoirs of precious metals, playing a crucial role in global mining operations. The Anatolian Peninsula, predominantly characterized by relatively young (Tertiary) lithologies, hosts numerous occurrences of epithermal base and precious metal mineralization. Within the realm of research in Northeastern Anatolia, several hydrothermal alteration zones have emerged as indicators of concealed epithermal mineralization, with the Bahçecik mineralization standing out as a recent focal point. The Bahçecik mineralization represents an intermediate sulfidation epithermal Au-Ag system, hosted by Late Cretaceous andesitic rocks, as well as Eocene dacitic lava and tuffs. Employing U-Pb LA-ICP-MS zircon dating of the dacitic host rocks, the mineralization is estimated to have occurred during the Lutetian epoch (43.61 ± 0.35 Ma) or later. The genesis of the Bahçecik deposit is believed to be linked to postcollisional regional extensional tectonics, primarily controlling its structural arrangement. Comprising pyrite, chalcopyrite, low-Fe sphalerite, galena, tetrahedrite/tennantite, enargite-luzonite, and gold-silver minerals, the deposit is accompanied by prominent gangue minerals such as Mn- and Ca-carbonates, quartz, and barite. Microprobe measurements have identified a majority of Au-Ag minerals (krennerite, buckhornite, and nagyagite) closely associated with sulphide minerals. Fluid inclusion data reveal that mineralization and fluid transportation occurred at temperatures ranging from 153 to 327°C, with solutions exhibiting salinity levels consistent with those of intermediate sulfidation deposits (1.7–7.3 wt.% NaCl). This study unequivocally classifies the Bahçecik mineralization as an intermediate sulfidation deposit, contrary to the conclusions drawn in previous research. Moreover, our investigation has unveiled the presence of a substantial ore resource, totalling 7.84 million tons, featuring 1.76 g/t Au and 2.24 g/t Ag. As an intermediate-type deposit, it shares characteristics with other subtypes within the epithermal class, bridging the realms of both high and low sulfidation systems. [ABSTRACT FROM AUTHOR]

Copper is relatively low cost and highly abundant compared with the well-studied noble metals such as gold and silver. However, the poor plasmonic and high susceptibility towards oxidation limit the study of its optical properties and applications as well. Herein, copper nanoparticles@polycarbonate (Cu@PC) composites were prepared by using a facile one-step solvothermal method. The Cu@PC composites have strong localized surface plasmon resonances (LSPR) due to that the PC shell can induce the particles to form many-particles system with different particle numbers, which not only lead to overlap and hybridize of the LSPR modes, but also shift the LSPR away from the interband transitions, and the PC layer also prevents the oxidation of Cu nanoparticles. The photothermal conversion efficiency of Cu@PC composites reaches 41.1% under 808 nm continuous wave (CW) laser irradiation which is higher than previously reported Cu nanomaterials that have been reported. Meanwhile, the composites also have high photothermal stability. Moreover, interfacial evaporator is prepared by assembling the Cu@PC composites on scouring sponge as light absorption layer which has > 92.8% absorption in entire solar spectrum range. Its seawater evaporation rate is 3.177 kg·m−2·h−1 with a Eevaporator/Ewater of 5.2. The high evaporation rate interfacial evaporator with low cost, simple, and scalable approach shows great application value in the field of photothermal evaporation. [ABSTRACT FROM AUTHOR]

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With more and more lithium-ion batteries (LIBs) being put into production and application, precious metals such as lithium and cobalt are scarce, so it is imminent to recover various strategic metal resources from spent LIBs. Meanwhile, the complex and difficult problem of separating and recovering metals from leaching solutions has been an urgent question that needs to be resolved. In this work, a phosphoric acid-based deep eutectic solvent (DES) was developed for extracting metals from spent LIBs and one-step selectively separating and efficiently recovering transition metal. The prepared DES shows excellent extraction performance for Li (100%) and Co (92.8%) at 100 °C. In addition, the extraction system can effectively separate and precipitate Co through its own components, avoiding the introduction of new precipitants and the destruction of the original composition structure of DES. This also contributes to the good cycle stability of the extraction system with excellent extraction performance for Li (94.3%) and Co (80.8%) after 5 cycles. This work proposes a green method for one-step selectively separating and recovering valuable metals from spent LIBs. [ABSTRACT FROM AUTHOR]

Cross‐coupling of nitriles and alcohols offers an environmentally friendly and atom‐economical method for the synthesis of various valuable compounds. These compounds include α‐alkylated and α‐olefinated nitriles, primary amines, imines, N‐alkylation amines, amides, N‐heterocycles, δ‐hydroxynitriles, olefins, etc. Herein, we have reviewed recent developments (from 2013–date) of transition‐metal‐catalyzed cross‐coupling of nitriles and alcohols. A number of transition metal complexes such as noble metals Ru and Ir, as well as base metals Mn, Fe, Co, and Ni are presented. Moreover, different product types, reaction conditions and mechanisms are discussed to understand the reaction and catalyst development. [ABSTRACT FROM AUTHOR]

Renewable energy‐driven proton exchange membrane water electrolyzer (PEMWE) attracts widespread attention as a zero‐emission and sustainable technology. Oxygen evolution reaction (OER) catalysts with sluggish OER kinetics and rapid deactivation are major obstacles to the widespread commercialization of PEMWE. To date, although various advanced electrocatalysts have been reported to enhance acidic OER performance, Ru/Ir‐based nanomaterials remain the most promising catalysts for PEMWE applications. Therefore, there is an urgent need to develop efficient, stable, and cost‐effective Ru/Ir catalysts. Since the structure‐performance relationship is one of the most important tools for studying the reaction mechanism and constructing the optimal catalytic system. In this review, the recent research progress from the construction of unsaturated sites to gain a deeper understanding of the reaction and deactivation mechanism of catalysts is summarized. First, a general understanding of OER reaction mechanism, catalyst dissolution mechanism, and active site structure is provided. Then, advances in the design and synthesis of advanced acidic OER catalysts are reviewed in terms of the classification of unsaturated active site design, i.e., alloy, core‐shell, single‐atom, and framework structures. Finally, challenges and perspectives are presented for the future development of OER catalysts and renewable energy technologies for hydrogen production. [ABSTRACT FROM AUTHOR]

The development of hydrogen storage and conversion technologies, such as electrolyzers and fuel cells, significantly benefits from the electrochemical deposition of platinum (Pt). This process is also crucial for creating coatings for internal combustion engines and electronic devices. Conventionally, Pt electrochemical deposition occurs in acidic media, which efficiently dissolves Pt salts but necessitates the use of expensive, corrosion-resistant substrates like noble metals and other critical raw materials such as titanium (Ti). This research explores the alkaline electrochemical deposition of Pt, aiming to overcome the limitations associated with acidic media. The study begins with developing strategies to dissolve commonly used Pt precursors from acidic baths into stable complexes suitable for alkaline environments. Various protocols, including chronoamperometric and potentiometric ones, are employed to evaluate the Pt electrodeposition on substrates such as nickel (Ni) foams and stainless steel meshes, which are relevant to alkaline water electrolysis. Optimization of the electrochemical deposition parameters is carried out to enhance the hydrogen evolution reaction (HER) activity of the resulting electrodes. The most HER-active electrodes are then tested as cathodes in alkaline electrolyzers (AELs), demonstrating superior performance compared to commercially available platinized Ti felts. These advanced AELs can operate at high current densities (≥1 A cm⁻2) at cell voltages below 2 V, thereby rivaling state-of-the-art acidic water electrolysis systems. Looking forward, the alkaline electrodeposition of Pt presents a sustainable approach to the usage of Pt in green hydrogen production. Pt recovered from operating or end-of-life electrolyzers and fuel cells can be reused to restore or enhance the catalytic activity of cathodes in alkaline water electrolysis, ensuring efficient and eco-friendly Pt utilization. [Display omitted] • Alkaline electrochemical deposition of Pt explored on various substrates used in AELs and AEM-ELs. • Pt precursors can form stable complexes in 1 M and 6.9 M KOH at 70 °C. • Fine-tuned Pt films achieve overpotential as low as 0.067 V at −100 mA cm⁻2. • Electrochemically deposited Pt films were validated in high-performance AEL cells. • In-situ electrochemical Pt deposition can be used for upgrading/healing AEL and AEM-EL cathodes. [ABSTRACT FROM AUTHOR]

A mechanochemical approach through ball milling (BM) to produce NiO clusters supported on TiO 2 has been successfully applied, resulting in a NiO/TiO 2 p-n heterojunction as an efficient and sunlight-sensitive photocatalyst. Besides, the synergistic interaction between NiO and TiO 2 (P90) enhances charge separation, ultimately boosting the H 2 photoproduction. Notably, the material obtained by BM, denoted as NiO/P90-BM achieved an H 2 evolution rate that was over 12 times higher than that of Neat P90 (8.85 mmol h−1 g−1 vs. 0.73 mmol h−1 g−1). The predominance of the high-spin configuration for Ni2+ in NiO was ascribed as one of the main reasons for such performance. Additionally, photoelectrochemical measurements revealed that NiO addition was beneficial for the photoelectrochemical properties. The NiO/P90-BM exhibited the lowest charge transfer resistance, the highest photocurrent signal, and the highest electronic density. Furthermore, the achieved H 2 evolution rate is on par with that of materials produced using noble metals and energy-intensive approaches. Noticeably, cycling, long-term, and aging tests have shown that the reported photocatalyst is efficient after several cycles, prolonged use, and after long periods of storage. [Display omitted] • One-step ball milling process led to a NiO/TiO 2 p-n heterojunction. • The addition of NiO boosted sunlight absorption. • This noble metal-free photocatalyst exhibited an outstanding H 2 evolution rate. • High-spin of Ni2+ in NiO was crucial for such outstanding performance. • NiO/P90-BM performs comparably to noble metal-based and energy-intensive materials. [ABSTRACT FROM AUTHOR]

Nickel-catalyzed C–H bond functionalization reactions provide an impressive alternative to those with noble metal catalysts due to their unique reactivity and low cost. However, the regioselective C(sp2)–H borylation reaction of arenes accomplished by nickel catalyst remains limited. We herein disclose a silyl-directed ortho C(sp2)–H borylation of substituted arenes with a Ni(cod)2/PMe3/KHMDS catalyst system. Using readily available starting materials, this protocol provides easy access to ortho-borylated benzylic hydrosilanes bearing flexible substitution patterns. These products can serve as versatile building blocks for the synthesis of sila or sila/borine heterocycles under mild conditions. Control experiments and DFT calculations suggest that a catalytic amount of base prompts the formation of Ni(II)-Bpin-ate complex, likely related to the C(sp2)–H bond activation. This borylation reaction might follow an unusual Ni(II)/Ni(IV) catalytic cycle. Nickel-catalyzed C–H bond functionalization reactions provide an impressive alternative to those with noble metal catalysts but the regioselective C(sp2)−H borylation reaction of arenes accomplished by nickel catalyst remains challenging. Here the authors disclose a silyl-directed ortho C(sp2)−H borylation of substituted arenes with a Ni(cod)2/PMe3/KHMDS catalyst system. [ABSTRACT FROM AUTHOR]

CeO2‐supported noble metal clusters are attractive catalytic materials for several applications. However, their atomic dispersion under oxidizing reaction conditions often leads to catalyst deactivation. In this study, the noble metal cluster formation threshold is rationally adjusted by using a mixed CeO2‐Al2O3 support. The preferential location of Pd on CeO2 islands leads to a high local surface noble metal concentration and promotes the in situ formation of small Pd clusters at a rather low noble metal loading (0.5 wt %), which are shown to be the active species for CO conversion at low temperatures. As elucidated by complementary in situ/operando techniques, the spatial separation of CeO2 islands on Al2O3 confines the mobility of Pd, preventing the full redispersion or the formation of larger noble metal particles and maintaining a high CO oxidation activity at low temperatures. In a broader perspective, this approach to more efficiently use the noble metal can be transferred to further systems and reactions in heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Cobalt catalysts have recently gained considerable attention as alternatives to catalysts based on precious transition metals such as Rh and Ir. Recently, Co/photoredox cooperative catalysis has emerged as a powerful tool that enables versatile transformations, including cycloaddition reactions of unsaturated compounds. In particular, 1,6‐diyne derivatives are fascinating substrates for these reactions because the corresponding exocyclic 1,3‐diene products can be further transformed into sp3‐rich carbocycles and heterocycles via functionalization of the diene moiety. The dual catalytic system can facilitate not only the cycloaddition based on the activation of the π‐bond only, such as alkyne cyclotrimerization, but also the cycloaddition involving σ‐bond activation. This Concept highlights the recent advances in Co/photoredox cooperative‐catalysis‐enabled cycloaddition reactions, focusing on the reactions of 1,6‐diyne substrates, which are difficult to perform when well‐defined cationic CoI catalysis is employed. [ABSTRACT FROM AUTHOR]

Common half-cell measurements deliver oxygen reduction activities linked to the chosen scan rate, limiting their value for fundamental and comparative studies on platinum. Here we show a deconvolution of the intrinsic kinetics from the effect of surface oxygen on platinum. We find an electronic effect of the surface oxygen, substantiate a Tafel slope of ~120 mV/decade, obtain an exchange current density of 13 ± 4 µA/cm2, and an activity of 7 mA/cm2 at 900 mV. Eventually, we broaden the scope of this analysis to the effects of surface rearrangement, alloying, and supported Pt nanoparticles, the latter providing insight into discrepancies between half-cell and fuel cell measurements. We find through computational methods that binding energies of intermediates would be weakened by the presence of highly coordinated oxygen atoms. Finally, we obtain a phenomenological rate equation for the oxygen reduction and evolution reaction, suggesting that both reactions follow a shared mechanism. Catalyzing the splitting and formation of oxygen on noble metal surfaces are key reactions developing materials for electrolysis. Here, authors show on platinum that the state of a surface oxidation process is a key descriptor for the kinetics. [ABSTRACT FROM AUTHOR]

The rising demand and financial costs of noble transition metal catalysts have emphasized the need for sustainable catalytic approaches. Over the past few years, base‐metal catalysts have emerged as ideal candidates to replace their noble‐metal counterparts because of their abundance and easiness of handling. Despite the significant advancements achieved with precious transition metals, earth‐abundant cobalt catalysts have emerged as efficient alternatives for allylic substitution reactions. In this review, allylic alkylations at sp3‐carbon centers mediated by cobalt will be discussed, with a special focus on the mechanistic features, scope, and limitations. [ABSTRACT FROM AUTHOR]

In this work, Au/Bi2O3 was synthesized by loading Au nanoparticles (NPs) onto β-Bi2O3 by a simple solution reduction method. β-Bi2O3 was synthesized by a precipitation-thermal decomposition procedure, which results in significantly improved SERS detection limits down to 10−9 M for methylene blue (MB) and 10−7 M for methyl orange (MO) as probe molecules, comparable to those reported for the best semiconductor SERS substrates. In particular, further deposition of Au NPs (5.20% wt%) onto β-Bi2O3 results in a two-order-of-magnitude enhancement in detection sensitivity, achieving a detection limit of 10−11 M for MB and 10−9 M for MO. Under ultraviolet/visible irradiation, the Au/Bi2O3 hybrids substrate exhibits superior self-cleaning ability due to its photocatalytic degradation ability which can be applied repeatedly to the detection of pollutants. The advanced composite substrate simultaneously achieved ultra-low mass loading of Au NPs, outstanding detection performance, good reproducibility, high stability and self-cleaning ability. The development strategy of low load noble metal coupled high performance semiconductor β-Bi2O3 to obtain nano-hybrid materials provides a method to balance SERS sensitivity, cost effectiveness and operational stability, and can be synthesized in large quantities, which is a key step towards commercialization and has good reliability prospects. [ABSTRACT FROM AUTHOR]

The design and development of new large-capacity and selective materials for extracting rare precious metals via electronic waste is practically essential. In this paper, a new efficient UiO-66-NCS has been obtained as a consequence of the modification of the classical Zr-MOF (UiO-66-NH2), and its ability to recover gold has been investigated. These batch results adequately illustrated that UiO-66-NCS exhibited good adsorption capacity (675.5 mg g−1) and exceptional selectivity. In addition, UiO-66-NCS achieved faster adsorption equilibrium times of about 120 min. Adsorption kinetics and isotherms demonstrated that the pseudo-second-order adsorption scheme and a Langmuir-type procedure were shown by the adsorption of Au(III) on UiO-66-NCS. Characterized by pH effect experiments, TEM, XRD, and XPS, the adsorption of UiO-66-NCS with Au(III) relies on coordination, which further results in reduction, and the generated Au(0) is uniformly dispersed in the MOF. The adsorbent has considerable advantages for cyclic regeneration. Finally, DFT fitting results showed that the adsorption binding energy of UiO-66-NCS with [AuCl4]− was −8.63 kcal mol−1 for the adsorption process. UiO-66-NCS is likely to be an ideal substance for gold recovery. [ABSTRACT FROM AUTHOR]

Palladium and platinum are precious metals (PMs) used in industrial catalysis, and their green recycling is crucial but challenging. In this study, we aimed to create a novel leaching procedure for the environmentally friendly recovery of PMs using AlCl3·6H2O solution. We report here the use of a microwave-assisted AlCl3·6H2O solution to selectively recover Pd and Pt from spent catalysts. In a large-scale setting, our system can recover gram-scale Pd in a single batch. Electron paramagnetic resonance (EPR) and capture experiments revealed the hydroxyl radicals produced by proton dissociation and microwave coordination triggered the oxidative dissolution process. Microwave-assisted AlCl3·6H2O solution leaching and NaBH4 reduction recovered high-purity Pd and Pt separately. In scale-up experiments, the dissolution performance of the microwave-assisted AlCl3·6H2O solution for Pd remained almost unchanged after seven cycles. Our approach uses around 1/50 and 1/20 of the energy and chemical inputs of the conventional hydrometallurgy process, respectively. Strong acids, poisonous cyanide, and volatile organic solvents were not used during the recovery process, enabling an efficient and sustainable PM recovery process and promoting an advanced oxidation process (AOPs) technology for secondary resource recycling. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting stands out as a highly effective and environment‐friendly strategy for generating pure hydrogen. However, the expensive catalyst required, and the low efficiency of water electrolysis, are still of concern. Herein, a novel Rh–CoSe2/CoSeO3 nanocubes heterostructure is designed with a successful robust coupling between CoSe2 and CoSeO3, and employed as a bifunctional electrocatalyst for the water splitting system. The interaction enhances metal–substrate bonding and generates the anchor sites for intermediate species, which increases the electrocatalytic efficiency and mass transport kinetics, and offers exceptional stability. The water‐splitting device demonstrates remarkable performance, with a low voltage of 1.62 V at a current density of 20 mA cm−2 and long‐lasting durability for ‐100 h. This study opens a new avenue toward the creation of extremely effective and long‐lasting catalysts to be used at an industrial scale to allow alkaline water splitting and for other energy conversion devices. The Rh–CoSe2/CoSeO3 heterostructure offers promising prospects for advancing sustainable energy technologies and positively impacting the clean energy of the future. [ABSTRACT FROM AUTHOR]

Well-defined metal nanoclusters protected by thiolates, with sizes between nanocrystals and metal atoms, have attracted enormous attention due to their various structures, controllable compositions, intriguing physical and chemical properties, and potential applications. Atomically precise metal nanoclusters are a type of important nanomaterial that can provide an ideal platform to address some key challenges related to their applications. However, compared to the straightforward synthesis of larger nanoparticles, the preparation of ultra-small metal nanoclusters frequently encounters difficulties owing to the pursuit of monodispersity and atomic accuracy. Although a series of effective synthesis methods have been developed for metal nanoclusters with well-defined sizes, structures and compositions, rational design and successful preparation of atomically precise metal nanoclusters still face challenges that further hinder the enrichment of cluster libraries and the in-depth understanding of structure–property relationships. In this review, we summarize some recent advances in strategies for the synthesis of atomically precise metal nanoclusters, in particular, silver and gold nanoclusters as well as alloy nanoclusters, and emphasize the following synthesis methods including the Brust–Schiffrin method, ligand-exchange, galvanic/anti-galvanic reaction, etching, solid phase synthesis and intercluster reaction. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm, which focuses on the design and understanding of solid-state and crystalline materials. It includes a cover image by Gonzalo Campillo-Alvarado and an inside cover image by Shuai Wang and Xiaoyang Dai. The highlighted articles in this issue include one on multiple synthesis routes for atomically precise noble metal nanoclusters by Lizhong He and Tingting Dong, and another on co-crystal formation versus boron coordination in azopyridines by Jesus Daniel Loya, Sidhaesh A. Agarwal, Nicholas Lutz, Eric W. Reinheimer, and Gonzalo Campillo-Alvarado. The document also mentions professional development opportunities and provides a list of papers featured in the journal. [Extracted from the article]

Graphitic carbon nitride (g-C3N4), known for being nontoxic, highly stable, and environmentally friendly, is extensively used in photocatalytic degradation technologies. Silver nanoparticles effectively capture the photogenerated electrons in g-C3N4, enhancing the photocatalytic efficiency. This study primarily focused on synthesizing graphitic carbon nitride via thermal polymerization and depositing noble metal silver onto g-C3N4 through photoreduction. Methyl orange (MO) and methylene blue (MB) were targeted as the pollutants in the photocatalytic experiments under visible light in conjunction with a H2O2 system. The characteristics peaks, structure, and morphology were analyzed using Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). g-C3N4 loaded with 6% Ag exhibited superior photocatalytic performance; the photocatalytic fraction of the degraded materials of the MO and MB solutions reached 100% within 70 and 80 min, respectively, upon adding 1 mL and 2 mL of H2O2. ·OH and ·O2− were the primary active free radicals in the dye degradation process within the synergistic system. Stability tests also demonstrated that the photocatalyst maintained good reusability under the synergistic system. [ABSTRACT FROM AUTHOR]

4-(2-furyl)-3-buten-2-one (FAc) is obtained by aldol condensation of furfural and acetone and has been used in hydrodeoxygenation reactions to obtain fuel products using noble metal catalysts. The hydrogenation of FAc in the aqueous phase using metallic- and Re oxide-supported catalysts on graphite was studied, within a temperature range of 200–240 °C, in a batch reactor over a 6 h reaction period. The catalysts were characterized using N2 adsorption–desorption, TPR-H2, TPD-NH3, XRD, and XPS analyses. Catalytic reactions revealed that metallic rhenium and rhenium oxide-supported catalysts are active for the hydrogenation and Piancatelli rearrangement of FAc. Notably, metallic rhenium exhibited a fourfold higher initial rate than rhenium oxide, which was attributed to the higher dispersion of Re in the Re/G catalyst over graphite. Re/G and ReOx/G catalysts tended to rearrange and hydrogenate FAc to 2-(2-oxopropyl)cyclopenta-1-one in water. [ABSTRACT FROM AUTHOR]

Creating heterojunctions or composites by incorporating noble metals offers a remarkable means to modulate the electronic charge transfer and the nonlinear optical (NLO) properties in 2D transition metal dichalcogenides (TMDCs). The response of such 2D‐TMDC‐noble metal composites to femtosecond (fs) infrared (IR) and terahertz (THz) radiation, however, remains vastly unexplored. While the linear optical characteristics of a prototypical 2D‐TMDC, namely, MoSe2 nanosheets incorporated with noble metal (such as Au, Pt, and Ag) nanoparticles in the UV–Vis and the THz spectral range, the NLO characteristics are measured using a 70‐fs pulse at 800 nm excitation is investigated. The results demonstrate a clear reduction of band gap with the incorporation of noble metals in MoSe2, indicating an effective charge transfer mechanism at play. Notably, the MoSe2‐noble metal nanocomposites depicted a significant enhancement in the THz conductivities. In addition, a dramatic 4‐fold enhancement in the third‐order nonlinear coefficient and ≈2‐fold enhancement in the third‐order NLO susceptibility is achieved in MoSe2‐Ag nanocomposite. These results univocally suggest that the noble metal‐based composites with suitable charge transfer channels promote enhanced carrier mobilities and tunable electron transfer dynamics, making these hybrid materials promising candidates for optoelectronic applications both at IR and THz frequencies. [ABSTRACT FROM AUTHOR]

2D orthorhombic palladium diselenide is attracting rapidly increased interest by virtue of its fascinating physical properties and feasibility of phase transformation. However, it remains a major challenge to produce ultrathin PdSe2 through a facile chemical route and control phase transformation because of its anisotropic structure with strong interlayer coupling. Here, the efficient synthesis of few‐layer PdSe2 nanosheets with large sizes using an electrochemical exfoliation approach is reported. Upon thermal annealing at 300–350 °C, the as‐exfoliated PdSe2 nanosheets transform into metallic phase PdSe2‐x, as verified by scanning transmission electron microscopy, Raman spectroscopy, and electrical characterizations. Simple encapsulation using hexagonal boron nitride (h‐BN) can effectively suppress the Se‐loss triggered phase transformation, so that a metal‐semiconductor junction is formed by local phase modification. The fabricated PdSe2 field‐effect transistors exhibit p‐type transport property, which is in stark contrast to electron‐dominated ambipolar transport of pristine PdSe2 devices. The combination of high‐resolution X‐ray photoelectron spectroscopy and cross‐sectional transmission electron microscopy analysis reveals that the modulation of carrier polarity in h‐BN encapsulated PdSe2 should arise from the p‐doping effect associated with the impact of interfacial condition. The study opens up a new route for future phase‐engineered electronics in PdSe2 and other 2D noble metal dichalcogenides materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CoNiFe 0.08 -NC@p-NCNTs is synthesized by DBD plasma treatment. • NC encapsulated CoNiFe NPs constructed nanosheets distribute on the network of NCNTs. • The CoNiFe 0.08 -NC@p-NCNTs is demonstrated to be an excellent catalyst for ORR/OER. • It shows great potentials in improving the performance of rechargeable ZABs. • The assembled flexible all-solid-state ZAB exhibits a high OCV of 1.384 V. Economical oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) bifunctional catalysts with high activity aimed at replacing precious metal catalysts for rechargeable zinc-air batteries (ZABs) must be developed. In this study, a multiple hierarchical-structural material is developed using a facile dielectric barrier discharge (DBD) plasma surface treatment, solvothermal reaction, and high-temperature carbonization strategy. This strategy allows for the construction of nanosheets using nitrogen-doped carbon (NC) material-encapsulated ternary CoNiFe alloy nanoparticles (NPs) on a network of NC nanotubes (NCNTs), denoted as CoNiFe–NC@p–NCNTs. Precisely, the presence of abundant CoNiFe alloy NPs and the formation of M–N–C active sites created by transition metals (cobalt, nickel, and iron) coupled with NC can provide superior OER/ORR bifunctional properties. Moreover, the prepared NC layers with a multilevel pore structure contribute to a larger specific surface area, exposing numerous active sites and enhancing the uniformity of electron and mass movement. The CoNiFe 0.08 –NC@p–NCNTs show remarkable dual functionality for electrochemical oxygen reactions (ORR half-wave potential of 0.811 V, limiting current density of 5.73 mA cm−2 measured with a rotating disk electrode at a rotation speed of 1600 rpm, and OER overpotential of 351 mV at 10 mA cm−2), which demonstrates similar ORR performance to 20 wt% Pt/C and better OER performance than the commercial RuO 2. A liquid ZAB prepared using the proposed material has excellent bifunctionality with an open-circuit voltage of 1.450 V and long-term cycling stability of 230 h@10 mA cm−2. [ABSTRACT FROM AUTHOR]

Noble metal nanoparticles decorated on a catalyst support with a large specific surface area can exhibit enhanced catalytic activity. To this end, a synthetic method to heterogeneously and evenly nucleate platinum nanoparticles (Pt NPs) onto mesoporous silica nanoparticles (MSNs) is developed. The obtained Pt NP-modified MSNs (Pt-MSNs) are characterized as a thin layer of 3 nm-sized Pt NPs densely assembled on the MSN surface, by which the throughput of the peroxidase-like activity of Pt-MSNs is greatly improved. The utility of Pt-MSNs in colorimetric detection of analytes is validated for two different assay schemes. Firstly, colloidally dispersed Pt-MSNs are employed as a peroxidase-mimic in a two-step cascade reaction to quantitate glucose/cholesterol based on the amount of H2O2 produced by glucose/cholesterol oxidase. Secondly, detection of C-reactive protein (CRP) is conducted on a solid substrate by adopting a sandwich immunoassay format. Detection limits are estimated to be 20 μM, 55 μM, and 3.9 pM for glucose, cholesterol, and CRP, respectively. [ABSTRACT FROM AUTHOR]

Recovering platinum group precious metals (PGMs) from used industrial catalysts is crucial and challenging. This study delves into an environmentally friendly approach to selectively recover PGMs from commercial air purifiers using photocatalytic redox technology. We harness sunlight as the energy source to activate the photocatalysts, facilitating the complete dissolution of precious metals under natural light irradiation. [Display omitted] The mitigation of environmental and energy crises could be advanced by reclaiming platinum group precious metals (PGMs) from decommissioned air purification catalysts. However, the complexity of catalyst composition and the high chemical inertness of PGMs significantly impede this process. Consequently, recovering PGMs from used industrial catalysts is crucial and challenging. This study delves into an environmentally friendly approach to selectively recover PGMs from commercial air purifiers using photocatalytic redox technology. Our investigation focuses on devising a comprehensive strategy for treating three-way catalysts employed in automotive exhaust treatment. By meticulously pretreating and modifying reaction conditions, we achieved noteworthy results, completely dissolving and separating rhodium (Rh), palladium (Pd), and platinum (Pt) within a 12-h time frame. Importantly, the solubility selectivity persists despite the remarkably similar physicochemical properties of Rh, Pd, and Pt. To bolster the environmental sustainability of our method, we harness sunlight as the energy source to activate the photocatalysts, facilitating the complete dissolution of precious metals under natural light irradiation. This eco-friendly recovery approach demonstrated on commercial air purifiers, exhibits promise for broader application to a diverse range of deactivated air purification catalysts, potentially enabling implementation on a large scale. [ABSTRACT FROM AUTHOR]