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Absolute measurements of solid-material compressibility by magnetically driven shockless dynamic compression experiments to multi-megabar pressures have the potential to greatly improve the accuracy and precision of pressure calibration standards for use in diamond anvil cell experiments. To this end, we apply characteristics-based inverse Lagrangian analysis (ILA) to 11 sets of ramp-compression data on pure platinum (Pt) metal and then reduce the resulting weighted-mean stress–strain curve to the principal isentrope and room-temperature isotherm using simple models for yield stress and Grüneisen parameter. We introduce several improvements to methods for ILA and quasi-isentrope reduction, the latter including calculation of corrections in wave speed instead of stress and pressure to render results largely independent of initial yield stress while enforcing thermodynamic consistency near zero pressure. More importantly, we quantify in detail the propagation of experimental uncertainty through ILA and model uncertainty through quasi-isentrope reduction, considering all potential sources of error except the electrode and window material models used in ILA. Compared to previous approaches, we find larger uncertainty in longitudinal stress. Monte Carlo analysis demonstrates that uncertainty in the yield-stress model constitutes by far the largest contribution to uncertainty in quasi-isentrope reduction corrections. We present a new room-temperature isotherm for Pt up to 444 GPa, with 1-sigma uncertainty at that pressure of just under ± 1.2 % ; the latter is about a factor of three smaller than uncertainty previously reported for multi-megabar ramp-compression experiments on Pt. The result is well represented by a Vinet-form compression curve with (isothermal) bulk modulus K 0 = 270.3 ± 3.8 GPa, pressure derivative K 0 ′ = 5.66 ± 0.10 , and correlation coefficient R K 0 , K 0 ′ = − 0.843. [ABSTRACT FROM AUTHOR]

Dynamic shockless compression experiments provide the ability to explore material behavior at extreme pressures but relatively low temperatures. Typically, the data from these types of experiments are interpreted through an analytic method called Lagrangian analysis. In this work, alternative analysis methods are explored using modern statistical methods. Specifically, Bayesian model calibration is applied to a new set of platinum data shocklessly compressed to 570 GPa. Several platinum equation-of-state models are evaluated, including traditional parametric forms as well as a novel non-parametric model concept. The results are compared to those in Paper I obtained by inverse Lagrangian analysis. The comparisons suggest that Bayesian calibration is not only a viable framework for precise quantification of the compression path, but also reveals insights pertaining to trade-offs surrounding model form selection, sensitivities of the relevant experimental uncertainties, and assumptions and limitations within Lagrangian analysis. The non-parametric model method, in particular, is found to give precise unbiased results and is expected to be useful over a wide range of applications. The calibration results in estimates of the platinum principal isentrope over the full range of experimental pressures to a standard error of 1.6%, which extends the results from Paper I while maintaining the high precision required for the platinum pressure standard. [ABSTRACT FROM AUTHOR]

Atomic layer deposition is a key technique for preparing large area uniformity, three-dimensional conformal, and ultrathin films due to its sequential self-limiting saturated chemisorption properties. Electric fields of varying magnitudes and directions were applied on Si, Al2O3, Au, and Ni substrates in Pt plasma enhanced atomic layer deposition processes. Studying the influences of electric fields on the initial nucleation and growth of Pt films on different substrates helps to understand the dynamic knowledge and underlying physical mechanisms so as to obtain ultrathin, continuous films and full control over the morphology and distribution of deposited materials. The XPS results reveal that the Pt coverage rate increases on all substrates with applied voltages. The induced dipole moment causes the (MeCp)PtMe3 molecule to rotate in a certain direction resulting in a more compact arrangement, and the energy generated by electric fields also helps the dissociation of methyl, ethyl, Cp, and MeCp ligands, which greatly mitigate the spatial site resistance effect, thus improving initial monolayer chemisorption efficiency and the Pt coverage. We also find that Pt prefers to grow in the (111) direction due to the increase in adsorption of (MeCp)PtMe3 molecules caused by the gradient forces under electric fields. However, applied electric fields can also influence the morphology by inducing surface diffusion and acting on plasma species. [ABSTRACT FROM AUTHOR]

The rate of CO formation from CO2 reduction on Pt(111) vicinal surfaces containing (100) steps, Pt(S)[n(111) × (100)], has been investigated using cyclic voltammetry. To obtain further information about the different roles of terrace and step atoms in this reaction, selective modification of step sites with either bismuth or copper has been performed. In this way, two different mechanistic regimes have been differentiated, depending on the potential range. In the high potential region, between 0.2 and 0.4 V RHE, CO2 is activated on steps and proceeds to the formation of adsorbed CO even when there is no hydrogen adsorbed on the terrace. We suggest that protonation of the activated CO2 uses protons from the solution. In this potential range, the activity decreases after the selective blockage of step sites with bismuth, while the deposition of copper on steps increases the activity. Contrarily, in the low potential region, below 0.2 V RHE, the presence of copper on the steps does not increase the amount of CO formed from CO2 reduction. In fact, the amount of CO formed attains the same saturation value with or without copper. In addition, the CO formed in this potential region remains adsorbed near step sites as shown in the voltammetric profile. We rationalize these observations considering that, in this potential region, activated CO2 reacts with adsorbed hydrogen and the reactions stop when hydrogen near the steps is depleted. [ABSTRACT FROM AUTHOR]

Rovibrational levels of low-lying electronic states of the diatomic molecule PtH are computed using non-relativistic wavefunction methods and a relativistic core pseudopotential. Dynamical electron correlation is treated at the coupled-cluster with single and double excitations and a perturbative estimate of triple excitations level, with basis-set extrapolation. Spin–orbit coupling is treated by configuration interaction in a basis of multireference configuration interaction states. The results compare favorably with available experimental data, especially for low-lying electronic states. For the yet-unobserved first excited state, Ω = 1/2, we predict constants including Te = (2036 ± 300) cm−1 and ΔG1/2 = (2252.5 ± 8) cm−1. Temperature-dependent thermodynamic functions, and thermochemistry of dissociation, are computed from the spectroscopic data. The ideal-gas enthalpy of formation is Δ f H 298.15 o (PtH) = (449.1 ± 4.5) kJ mol−1 (uncertainties expanded by k = 2). The experimental data are reinterpreted, using a somewhat speculative procedure, to yield the bond length Re = (1.5199 ± 0.0006) Å. [ABSTRACT FROM AUTHOR]

A Gaussian approximation machine learning interatomic potential for platinum is presented. It has been trained on density-functional theory (DFT) data computed for bulk, surfaces, and nanostructured platinum, in particular nanoparticles. Across the range of tested properties, which include bulk elasticity, surface energetics, and nanoparticle stability, this potential shows excellent transferability and agreement with DFT, providing state-of-the-art accuracy at a low computational cost. We showcase the possibilities for modeling of Pt systems enabled by this potential with two examples: the pressure–temperature phase diagram of Pt calculated using nested sampling and a study of the spontaneous crystallization of a large Pt nanoparticle based on classical dynamics simulations over several nanoseconds. [ABSTRACT FROM AUTHOR]

We systematically explored NO activation at metal/oxide interfaces by the combination of Sr3Ti2O7, Sr3Fe2O7, CeO2, anatase-TiO2, ZrO2, and γ-Al2O3 supports and the platinum-group metal cluster (Pd4, Pt4, and Rh4) using slab-model density functional theory calculations. These metal clusters can be strongly adsorbed at these metal oxide surfaces. The Pt4 and Rh4 clusters show larger adsorption energies than the Pd4 cluster, yet the γ-Al2O3(100) surface shows smaller adsorption energies than other metal oxide surfaces. One oxygen vacancy close to the metal cluster was constructed to evaluate the NO activation at those metal/oxide interfaces. The O atom of NO refills the oxygen vacancy after NO dissociation, while the N adatom is left on the metal cluster. The exothermic process was identified for the NO activation except for the Sr3Fe2O7 case, indicating the significant role of the interplay between the metal cluster and oxygen vacancy. [ABSTRACT FROM AUTHOR]

Multimetallic NHC (N-heterocyclic carbene) complexes comprising platinum(II) centers are rare. Four new dinuclear platinum(II) complexes possessing a combination of NHC and Py/4-Cl(Py) ligands are presented. Both classical and mesoionic carbene (MIC) ligands have been employed for the complexation. All complexes have been characterized using standard spectroscopic tools. The coordination of both classical NHC and pyridine ligands around the platinum(II) center in complex [2] has been established by using single crystal XRD. [ABSTRACT FROM AUTHOR]

Thanks to their properties, stability, and multifunctionality, nanozymes are increasingly impacting several fields, including medicine, diagnostics, and environmental science. However, clear information about their catalytic properties and mechanisms is still lacking. Several critical issues are currently under discussions, such as the absence of univocally accepted catalytic mechanisms, standardized protocols for directly comparing nanozymes versus enzymes, and a comprehensive characterization of their performance in different chemical/biological environments. All these issues strongly limit the advancement of the field. Herein, nanozymes metrology and analysis of both catalytic mechanisms and methodological procedures are attempted, taking platinum nanozymes as a case study thanks to their multifunctional catalytic features. The oxidoreductase activities of Pt‐nanozymes (i.e., peroxidase‐, oxidase‐, and catalase‐like reactions) are critically investigated in different physical/chemical environments, clarifying fundamental aspects and providing general methodological guidelines for nanozyme properties characterization. Furthermore, PtNP activities are compared with natural enzymes in different conditions, and their performance and catalytic behavior are evaluated by calculating the turnover frequency (TOF) with different normalization strategies. The results highlight that Pt‐nanozymes are efficient catalysts, exhibiting outstanding catalase‐like activity. This work clarifies several key points concerning Pt‐nanozyme properties and general metrological issues, providing a workflow that can become a reference for several nanozymes characterizations. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL)‐active molecular materials have drawn increasing attention due to their promising applications for next‐generation display and optoelectronic technologies. Currently, it is challenging to obtain CPL materials with both large luminescence dissymmetry factor (glum) and high quantum yield (Φ). A pair of enantiomeric N N C‐type Pt(II) complexes (L/D)‐1 modified with chiral Leucine methyl ester are presented herein. Though the solutions of these complexes are CPL‐inactive, the spin‐coated thin films of (L/D)‐1 exhibit giantly‐amplified circularly polarized phosphorescences with |glum| of 0.53 at 560 nm and Φair of ~50 %, as well as appealing circular dichroism (CD) signals with the maximum absorption dissymmetry factor |gabs| of 0.37–0.43 at 480 nm. This superior CPL performance benefits from the hierarchical formation of crystalline fibrillar networks upon spin coating. Comparative studies of another pair of chiral Pt(II) complexes (L/D)‐2 with a symmetric N C N coordination mode suggest that the asymmetric N N C coordination of (L/D)‐1 are favorable for the efficient exciton delocalization to amplify the CPL performance. Optical applications of the thin films of (L/D)‐1 in CPL‐contrast imaging and inducing CP light generation from achiral emitters and common light‐emitting diode lamps have been successfully realized. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL)‐active molecular materials have drawn increasing attention due to their promising applications for next‐generation display and optoelectronic technologies. Currently, it is challenging to obtain CPL materials with both large luminescence dissymmetry factor (glum) and high quantum yield (Φ). A pair of enantiomeric N N C‐type Pt(II) complexes (L/D)‐1 modified with chiral Leucine methyl ester are presented herein. Though the solutions of these complexes are CPL‐inactive, the spin‐coated thin films of (L/D)‐1 exhibit giantly‐amplified circularly polarized phosphorescences with |glum| of 0.53 at 560 nm and Φair of ~50 %, as well as appealing circular dichroism (CD) signals with the maximum absorption dissymmetry factor |gabs| of 0.37–0.43 at 480 nm. This superior CPL performance benefits from the hierarchical formation of crystalline fibrillar networks upon spin coating. Comparative studies of another pair of chiral Pt(II) complexes (L/D)‐2 with a symmetric N C N coordination mode suggest that the asymmetric N N C coordination of (L/D)‐1 are favorable for the efficient exciton delocalization to amplify the CPL performance. Optical applications of the thin films of (L/D)‐1 in CPL‐contrast imaging and inducing CP light generation from achiral emitters and common light‐emitting diode lamps have been successfully realized. [ABSTRACT FROM AUTHOR]

This article demonstrates boron carbon nitrogen compound supported platinum group (Pd/BCN, Pt/BCN and Ru/BCN) for electrocatalytic reduction of nitrate to ammonia. [Display omitted] • Highly efficient electrocatalytic NO 3 – reduction was realized by doped Pd,Ru,Pt/BCN. • Pd/BCN provided higher NH 4 + production rate and Faraday efficiency. • DFT revealed the molecular mechanism of Pd/BCN in the nitrate reduction process. The effective treatment of nitrate (NO 3 −) in water as a nitrogen source and electrocatalytic NO 3 − reduction to ammonia (NH 3) (NRA) have become preferred methods for NO 3 −-to-NH 3 conversion. Achieving efficient NO 3 −-to-NH 3 conversion requires the design and development of electrode materials with high activity and efficiency for the electrocatalytic NRA reaction. Herein, based on the special properties of dodecahydro- closo -dodecaborate anions, a BCN matrix, loaded with platinum-group nanoparticles (namely, Pd/BCN, Pt/BCN, and Ru/BCN), was prepared using a simple method for the electrocatalytic NRA reaction. Results showed that Pd/BCN exerts the best catalytic effect on the NRA reaction. The NH 3 production rate reached 12.71 mg h−1 mg cat. −1 at −1.0 V vs. RHE. Faraday efficiency reached 91.79 %, which can be attributed to the more uniform distribution of the nanoparticles. Furthermore, Pd/BCN exhibited high cycling stability and resistance to ionic interference. Moreover, the density functional theory calculations indicated that small and well-distributed Pd nanoclusters in the BCN matrix have a large active surface area and promote the catalytic process. This study provides a new strategy to design catalysts for green ammonia synthesis. [ABSTRACT FROM AUTHOR]

Two N-alkyloxy-N′-phenylimidazolium proligands and the corresponding platinum(II) cyclometalated N-alkyloxyimidazol-2-ylidene complexes with β-diketonate auxiliary ligands, [(CNOHC^C*)Pt(L∩L)] (L∩L = acetyacetonate (acac) or 1,3-bis(2,4,6-trimethylphenyl)-propane-1,3-dionato (mesacac)) were synthesized and fully characterized. In addition, a Au(I) monocarbene complex was synthesized, isolated and characterized. Solid-state structures of two cyclometalated platinum(II) NOHC complexes and the Au(I) NOHC complex were obtained providing structural proof. [ABSTRACT FROM AUTHOR]

The synthesis, characterization and photocatalytic hydrogen evolution reaction (HER) performance of a series of metal–organic gels (MOGs) constructed from titanium(IV)-oxo clusters and dicarboxylato linkers (benzene-1,4-dicarboxylato and 2-aminobenzene-1,4-dicarboxylato) are described. All the MOGs exhibit a microstructure comprised of metal–organic nanoparticles intertwined into a highly meso-/macroporous structure, as demonstrated by cryogenic transmission electron microscopy and gas adsorption isotherms. Comprehensive chemical characterization enabled the estimation of the complex formula for these defective materials, which exhibit low crystallinity and linker vacancies. To gain deeper insights into the local structure, X-ray absorption fine structure (XAFS) spectroscopy experiments were performed and compared to that of the analogous crystalline metal–organic framework. Additionally, the ultraviolet–visible absorption properties and optical band gaps were determined from diffuse reflectance spectroscopy data. The MOGs were studied as light absorbers for the sacrificial photocatalytic HER under simulated solar light irradiation using a platinum co-catalyst by either (1) in situ photodeposition or (2) ex situ doping process, through a post-synthetic metalation of the MOG structure. The chemical analysis of the metalation, along with high-angle annular dark-field scanning transmission electron microscopy, revealed that although the in situ addition of the co-catalyst led to greater HER rates (227 vs. 110 μmolH2 gMOG−1 h−1 for in situ and ex situ, respectively), the ex situ modification provided a finer distribution of platinum nanoparticles along the porous microstructure and, as a result, it led to a more efficient utilization of the co-catalyst (45 vs. 110 mmolH2 gPt−1 h−1). [ABSTRACT FROM AUTHOR]

Collision‐induced dissociation (CID) of the mass‐selected cation [(bipy)Pt(CH3)2(CH2SCH3)]+ in an ion‐trap mass‐spectrometer results in the losses of the neutrals ethane, ethene, dimethyl sulfide, methane, ethyl methyl sulfide, and propane. The generation of the first four neutrals is also observed, when the isolated, dimeric complex [(bipy)Pt(CH3)2(CH2SCH3)]2[SbF6]2 is heated in the condensed phase. While the product distribution is very similar regardless of whether the complex is heated in the solid state or in solution, ethane loss, i. e. the quite rare event of an sp3‐sp3 C−C reductive elimination from a platinum(IV) complex, dominates in the gas‐phase experiment. However, when the counter anion [SbF6]− is exchanged by the more weakly coordinating anion [BAr4F]−, the amounts of ethane and ethene are increased also in the condensed phase. These sum of observations indicates the similarities of the fragmentation of [(bipy)Pt(CH3)2(CH2SCH3)]+ in both phases. Thus, a correlation of processes in both environments is possible for selected systems (and particularly for unimolecular processes), but the choice of the proper conditions is crucial for a meaningful comparison. [ABSTRACT FROM AUTHOR]

1,10‐Phenanthroline d‐ or f‐metal complexes can be utilised in biomedical applications such as imaging or therapeutics. Herein, we designed bimetallic d‐block metal‐phenanthroline f‐block metal‐1,4,7,10‐tetraazacyclododecane‐1,4,7,1,0‐tetraacetic acid (DOTA) conjugates as theranostic agents to simultaneously achieve both of these applications. Luminescence studies show the 1,10‐phenanthroline‐Eu(III)‐DOTA complexes displayed an off/on/off pH‐dependent switch, demonstrating their potential as pH‐responsive lanthanide luminescence probes. Relaxometry studies showed that the 1,10‐phenanthroline‐Gd(III)‐DOTA complexes present a r1 of 5.15±0.05 mM−1 s−1 and could thus be used as magnetic resonance (MR) contrast agents. Complexation of Pt(II) by the 1,10‐phenanthroline moiety resulted in quenching of the Eu(III) luminescence, but an enhancement of the Gd(III) relaxivity (r1=7.53±0.69 mM−1 s−1). Cell viability studies of the d–f hybrids in a cancer cell line showed the potential of these complexes as anticancer agents, as the IC50 for the Pt(II)/Gd(III) complex (IC50=24.9 μM) was lower than that of cisplatin (IC50=31.6 μM). As such, Pt(II)‐1,10‐phenanthroline‐Gd(III)‐DOTA complexes are promising theranostic agents for cancer therapy. [ABSTRACT FROM AUTHOR]

The synthesis of cone‐shaped Pt nanoparticles featuring compressively‐strained {111} facets by depositing Pt atoms on the vertices of Pd icosahedral nanocrystals, followed by selective removal of the Pd template via wet etching, is reported. By controlling the lateral dimensions down to ca. 3 nm, together with a thickness of ca. 2 nm, the Pt cones show greatly enhanced specific and mass activities toward oxygen reduction, with values being 2.8 and 6.4 times those of commercial Pt/C, respectively. Both the strain field and the observed activity trend are rationalized using density functional theory calculations. With the formation of ultrathin linkers among the Pt cones derived from the same Pd icosahedral seed, the interconnected Pt cones acquire stronger interactions with the carbon support, preventing them from detachment and aggregation during the catalytic reaction. Even after 20 000 cycles of accelerated durability test, the Pt cones still show a mass activity 5.3 times higher than the initial value of the Pt/C. [ABSTRACT FROM AUTHOR]

The stability of platinum‐based alloy catalysts is crucial for the future development of proton exchange membrane fuel cells, considering the potential dissolution of transition metals under complex operating conditions. Here, we report on a Rh‐doped Pt3Co alloy that exhibits strong interatomic interactions, thereby enhancing the durability of fuel cells. The Rh−Pt3Co/C catalyst demonstrates exceptional catalytic activity for oxygen reduction reactions (ORR) (1.31 A mgPt−1 at 0.9 V vs. the reversible hydrogen electrode (RHE) and maintaining 92 % of its mass activity after 170,000 potential cycles). Long‐term testing has shown direct inhibition of Co dissolution in Rh−Pt3Co/C. Furthermore, tests on proton exchange membrane fuel cells (PEMFC) have shown excellent performance and long‐term durability with low Pt loading. After 50,000 cycles, there was no voltage loss at 0.8 A cm−2 for Rh−Pt3Co/C, while Pt3Co/C experienced a loss of 200 mV. Theoretical calculations suggest that introducing transition metal atoms through doping creates a stronger compressive strain, which in turn leads to increased catalytic activity. Additionally, Rh doping increases the energy barrier for Co diffusion in the bulk phase, while also raising the vacancy formation energy of the surface Pt. This ensures the long‐term stability of the alloy over the course of the cycle. [ABSTRACT FROM AUTHOR]

The catalytic production of propylene via propane dehydrogenation (PDH) is a key reaction in the chemical industry. By combining operando transmission electron microscopy with density functional theory analysis, we show that the intercalation and ordering of carbon on Pt interstitials to form Pt−C solid solutions is relevant for increasing propylene production. More specifically, we found that at the point of enhanced propylene formation, the structure of platinum nanoparticles is transformed into a transient caesium chloride‐type Pt−C polymorph. At more elevated temperatures, the zincblende and rock salt polymorphs seemingly coexist. When propylene production was highest, multiple crystal structures consisting of Pt and carbon were occasionally found to coexist in one individual nanoparticle, distorting the Pt lattice. Catalyst coking was detected at all stages of the reaction, but did initially not affect all particles. These findings could lead to the development of novel synthesis strategies towards tailoring highly efficient PDH catalysts. [ABSTRACT FROM AUTHOR]

The stability of platinum‐based alloy catalysts is crucial for the future development of proton exchange membrane fuel cells, considering the potential dissolution of transition metals under complex operating conditions. Here, we report on a Rh‐doped Pt3Co alloy that exhibits strong interatomic interactions, thereby enhancing the durability of fuel cells. The Rh−Pt3Co/C catalyst demonstrates exceptional catalytic activity for oxygen reduction reactions (ORR) (1.31 A mgPt−1 at 0.9 V vs. the reversible hydrogen electrode (RHE) and maintaining 92 % of its mass activity after 170,000 potential cycles). Long‐term testing has shown direct inhibition of Co dissolution in Rh−Pt3Co/C. Furthermore, tests on proton exchange membrane fuel cells (PEMFC) have shown excellent performance and long‐term durability with low Pt loading. After 50,000 cycles, there was no voltage loss at 0.8 A cm−2 for Rh−Pt3Co/C, while Pt3Co/C experienced a loss of 200 mV. Theoretical calculations suggest that introducing transition metal atoms through doping creates a stronger compressive strain, which in turn leads to increased catalytic activity. Additionally, Rh doping increases the energy barrier for Co diffusion in the bulk phase, while also raising the vacancy formation energy of the surface Pt. This ensures the long‐term stability of the alloy over the course of the cycle. [ABSTRACT FROM AUTHOR]

The catalytic production of propylene via propane dehydrogenation (PDH) is a key reaction in the chemical industry. By combining operando transmission electron microscopy with density functional theory analysis, we show that the intercalation and ordering of carbon on Pt interstitials to form Pt−C solid solutions is relevant for increasing propylene production. More specifically, we found that at the point of enhanced propylene formation, the structure of platinum nanoparticles is transformed into a transient caesium chloride‐type Pt−C polymorph. At more elevated temperatures, the zincblende and rock salt polymorphs seemingly coexist. When propylene production was highest, multiple crystal structures consisting of Pt and carbon were occasionally found to coexist in one individual nanoparticle, distorting the Pt lattice. Catalyst coking was detected at all stages of the reaction, but did initially not affect all particles. These findings could lead to the development of novel synthesis strategies towards tailoring highly efficient PDH catalysts. [ABSTRACT FROM AUTHOR]

Low cathodic oxygen reduction reaction (ORR) efficiency is one of the important factors limiting the hydrogen fuel cells. Platinum can effectively reduce the ORR activation energy and improve the reaction rate; However, platinum's low reserves, versatility, and high price still limit its use in commercial, large-scale applications. It is very important to reduce the amount of Pt and improve the utilization rate and the stability of Pt-based catalyst. Here, an ultra-low Pt content catalyst Pt&Fe 2 O 3 /PM has been synthesized. The Pt content of the catalyst is only 4 wt%, and its nanoparticles are about 3 nm. Pt&Fe 2 O 3 /PM exhibit excellent ORR catalytic performance and longevity in acidic electrolyte. The ORR mechanism on Pt&Fe 2 O 3 /PM involves a direct four-electron path. The mass activity and specific activity of Pt&Fe 2 O 3 /PM is 4.8 and 10.3 times than that of commercial Pt/C, respectively. Furthermore, the catalyst's synthesis method is straightforward and amenable to scaling up, offering significant guidance for the creation of low-Pt catalysts. [Display omitted] • High dispersion low-Pt catalyst Pt&Fe 2 O 3 /PM was prepared by heat treatment. • The particle size of the Pt&Fe 2 O 3 /PM is ca. 3 nm, and the Pt content is ca. 4 wt%. • Pt&Fe 2 O 3 /PM has higher ORR activity and durability than commercial Pt/C. [ABSTRACT FROM AUTHOR]

Transition metal-containing materials with aggregation-induced emission (AIE) have brought new opportunities for the development of biological probes, optoelectronic materials, stimuli-responsive materials, sensors, and detectors. Coordination compounds containing the platinum metal have emerged as a promising option for constructing effective AIE platinum complexes. In this review, we classified AIE platinum complexes based on the number of ligands. We focused on the development and performance of AIE platinum complexes with different numbers of ligands and discussed the impact of platinum ion coordination and ligand structure variation on the optoelectronic properties. Furthermore, this review analyzes and summarizes the influence of molecular geometries, stacking models, and aggregation environments on the optoelectronic performance of these complexes. We provided a comprehensive overview of the AIE mechanisms exhibited by various AIE platinum complexes. Based on the unique properties of AIE platinum complexes with different numbers of ligands, we systematically summarized their applications in electronics, biological fields, etc. Finally, we illustrated the challenges and opportunities for future research on AIE platinum complexes, aiming at giving a comprehensive summary and outlook on the latest developments of functional AIE platinum complexes and also encouraging more researchers to contribute to this promising field. [ABSTRACT FROM AUTHOR]

Cyclometallated Pt(II) complexes possessing hydrophobic 2-phenylpyridine (ppy) ligands and hydrophilic acetonylacetone (acac) ligands have been investigated for their ability to detect amyloid fibrils via luminescence response. Using hen egg-white lysozyme (HEWL) as a model amyloid protein, Pt(II) complexes featuring benzanilide-substituted ppy ligands and ethylene glycol-functionalized acac ligands demonstrated enhanced luminescence in the presence of HEWL fibrils, whereas Pt(II) complexes lacking complementary hydrophobic/hydrophilic ligand sets displayed little to no emission enhancement. An amphiphilic Pt(II) complex incorporating a bis(ethylene glycol)-derivatized acac ligand was additionally found to trigger restructuring of HEWL fibrils into smaller spherical aggregates. Amphiphilic Pt(II) complexes were generally non-toxic to SH-SY5Y neuroblastoma cells, and several complexes also exhibited enhanced luminescence in the presence of Aß42 fibrils associated with Alzheimer's disease. This study demonstrates that easily prepared and robust (ppy)PtII(acac) complexes show promising reactivity toward amyloid fibrils and represent attractive molecular scaffolds for design of small-molecule probes targeting amyloid assemblies. [ABSTRACT FROM AUTHOR]

Efficient, electrochemically stable blue phosphors are essential for advancing the organic light‐emitting diode (OLED) industry. Specifically, the characteristics of these phosphors must be further refined to realize commercially viable OLED devices with high stability, efficiency, and color purity. To that end, a new simple molecular design approach is devised in this study for synthesizing tetradentate‐ligand‐based Pt(II) complexes exhibiting intense blue emission. Essentially, novel Pt(II) complexes Pt3 and Pt4 are prepared by introducing the tert‐butyl and cyano groups to the ligand of previously reported highly stable, efficient Pt(II) complexes for preventing molecular aggregation and regulating the frontier levels, respectively, and then fully characterized. Both complexes display a blue emission band in solution and solid states with remarkably low full‐width‐at‐half‐maximum values. Additionally, multilayer phosphorescent OLEDs are fabricated using Pt3 or Pt4 as emitters and SiCzCz/SiTrzCz2 as a mixed‐host system. The devices demonstrate outstanding performance parameters, such as higher efficiencies than those of the devices containing the previously reported Pt(II) complexes and good color purity (CIEy ≈ 0.18). These findings suggest that the molecular design approach employed in this study for creating tetradentate‐ligand‐based Pt(II) blue phosphors is effective and can potentially expedite the commercialization of blue phosphorescent emitters in the OLED industry. [ABSTRACT FROM AUTHOR]

Advanced-stage high-grade serous ovarian cancer (HGSOC) remains a deadly gynecologic malignancy with high rates of disease recurrence and limited, effective therapeutic options for patients. There is a significant need to better stratify HGSOC patients into platinum refractory (PRF) vs. sensitive (PS) cohorts at baseline to improve therapeutic responses and survival outcomes for PRF HGSOC. We performed NanoString for GeoMx Digital Spatial Profile (G-DSP) multiplex protein analysis on PRF and PS tissue microarrays (TMAs) to study the bidirectional communication of cancer cells with immune cells in the tumor microenvironment (TME) of HGSOC. We demonstrate robust stratification of PRF and PS tumors at baseline using multiplex spatial proteomic biomarkers with implications for tailoring subsequent therapy. PS patients had elevated apoptotic and anti-tumor immune profiles, while PRF patients had dual AKT1 and WNT signaling with immunosuppressive profiles. We found that dual activity of AKT1 and WNT signaling supported the exclusion of immune cells, specifically tumor infiltrating lymphocytes (TILs), from the TME in PRF tumors, and this was not observed in PS tumors. The exclusion of immune cells from the TME of PRF tumors corresponded to abnormal endothelial cell structure in tumors with dual AKT1 and WNT signaling activity. We believe our findings provide improved understanding of tumor-immune crosstalk in HGSOC TME highlighting the importance of the relationship between AKT and WNT pathways, immune cell function, and platinum response in HGSOC. [Display omitted] • High AKT1 activity resulted in low antigenicity and high immunoregulatory protein expression in HGSOC. • Immune cell influx was impaired in HGSOC tumors with dual WNT and AKT1 activity. • Dual WNT and AKT1 was highest in PRF HGSOC tumors. [ABSTRACT FROM AUTHOR]

Objectives: Long-term toxicities of germ cell cancer (GCC) treatment are of particular importance in young men with a life expectancy of several decades after curative treatment. This study aimed to investigate the long-term effects of platinum-based chemotherapy on cardiac function and myocardial tissue in GCC survivors by cardiac magnetic resonance (CMR) imaging. Methods: Asymptomatic GCC survivors ≥ 3 years after platinum-based chemotherapy and age-matched healthy controls underwent CMR assessment, including left ventricular (LV) and right ventricular (RV) ejection fraction (EF), strain analysis, late gadolinium enhancement (LGE) imaging, and T1/T2 mapping. Results: Forty-four survivors (age 44 [interquartile range, IQR 37–52] years; follow-up time 10 [IQR 5–15] years after chemotherapy) and 21 controls were evaluated. LV- and RVEF were lower in GCC survivors compared to controls (LVEF 56 ± 5% vs. 59 ± 5%, p = 0.017; RVEF 50 ± 7% vs. 55 ± 7%, p = 0.008). Seven percent (3/44) of survivors showed reduced LVEF (< 50%), and 41% (18/44) showed borderline LVEF (50–54%). The strain analysis revealed significantly reduced deformation compared to controls (LV global longitudinal strain [GLS] -13 ± 2% vs. -15 ± 1%, p < 0.001; RV GLS -15 ± 4% vs. -19 ± 4%, p = 0.005). Tissue characterization revealed focal myocardial fibrosis in 9 survivors (20%) and lower myocardial native T1 times in survivors compared to controls (1202 ± 25 ms vs. 1226 ± 37 ms, p = 0.016). Attenuated LVEF was observed after two cycles of platinum-based chemotherapy (54 ± 5% vs. 62 ± 5%, p < 0.001). Conclusion: Based on CMR evaluation, combination chemotherapy with cumulative cisplatin ≥ 200 mg/m2 is associated with attenuated biventricular systolic function and myocardial tissue alterations in asymptomatic long-term GCC survivors. Clinical relevance statement: Platinum-based chemotherapy is associated with decreased systolic function, non-ischemic focal myocardial scar, and decreased T1 times in asymptomatic long-term germ cell cancer survivors. Clinicians should be particularly aware of the risk of cardiac toxicity after platinum-based chemotherapy. Key Points: • Platinum-based chemotherapy is associated with attenuation of biventricular systolic function, lower myocardial T1 relaxation times, and non-ischemic late gadolinium enhancement. • Decreased systolic function and non-ischemic late gadolinium enhancement are associated with a cumulative cisplatin dose of ≥ 200 mg/m2. • Cardiac MRI can help to identify chemotherapy-associated changes in cardiac function and tissue in asymptomatic long-term germ cell cancer survivors. [ABSTRACT FROM AUTHOR]

Phosphor‐sensitized fluorescent (PSF) organic light‐emitting diodes (OLEDs) emerge as an attractive solution for realizing high‐performance displays with high color purity, meeting the Broadcast Television 2020 (BT.2020) requirements, by fully harnessing the benefits of both phosphorescent and fluorescent emitters. Herein, the synergistic effect of a Pt sensitizer and a boron (B)‐based multi‐resonance (MR)‐fluorescent emitter are introduced to enhance the efficiency of blue‐emitting PSF–OLEDs. Notably, it is confirmed that the interaction between the empty pz orbital in the boron atom of the MR emitter and the unpaired electrons in the dz2 orbital of the Pt emitter plays a crucial role. The combination results in an enhancement of the horizontal emitting dipole orientation (EDO) to 81%, a marked improvement compared to the individual components of Pt phosphor (69%) or MR emitter (78%). The synergistic approach leads to the realization of high‐performance blue‐emitting PSF‐OLEDs with a maximum external quantum efficiency of 25%, a peak intensity at 465 nm in the electroluminescence spectrum, and a full width at half maximum of 29 nm, achieved by enhancing the outcoupling. In these findings, insight is provided into design strategies for developing PSF systems based on Pt sensitizer and B‐terminal emitter to achieve efficient energy transfer as well as improved EDO. [ABSTRACT FROM AUTHOR]

Introduction This study investigated the efficacy and safety of neoadjuvant chemotherapy for locally advance penile squamous cell carcinoma for which current evidence is lacking. Methods Included patients had locally advanced penile squamous cell carcinoma with clinical lymph node metastasis treated with at least 1 dose of neoadjuvant chemotherapy prior to planned consolidative lymphadenectomy. Objective response rates were assessed using Response Evaluation Criteria in Solid Tumors v1.1. The primary and secondary outcomes were overall survival and progression-free survival, estimated by the Kaplan–Meier method. Treatment-related adverse events were graded per the Common Terminology Criteria for Adverse Events v5.0. Results A total of 209 patients received neoadjuvant chemotherapy for locally advanced and clinically node-positive penile squamous cell carcinoma. The study population consisted of 7% of patients with stage II disease, 48% with stage III, and 45% with stage IV. Grade 2 treatment-related adverse events occurred in 35 (17%) patients, and no treatment-related mortality was observed. Of the patients, 201 (97%) completed planned consolidative lymphadenectomy. During follow-up, 106 (52.7%) patients expired, with a median overall survival of 37.0 months (95% confidence interval [CI] = 23.8 to 50.1 months) and median progression-free survival of 26.0 months (95% CI = 11.7 to 40.2 months). Objective response rate was 57.2%, with 87 (43.2%) having partial response and 28 (13.9%) having a complete response. Patients with objective response to neoadjuvant chemotherapy had a longer median overall survival (73.0 vs 17.0 months, P  < .01) compared with those who did not. The lymph node pathologic complete response rate was 24.8% in the cohort. Conclusion Neoadjuvant chemotherapy with lymphadenectomy for locally advanced penile squamous cell carcinoma is well tolerated and active to reduce the disease burden and improve long-term survival outcomes. [ABSTRACT FROM AUTHOR]

Background: Platinum-based chemotherapy regimens are a mainstay in the management of ovarian cancer (OC), but emergence of chemoresistance poses a significant clinical challenge. The persistence of ovarian cancer stem cells (OCSCs) at the end of primary treatment contributes to disease recurrence. Here, we hypothesized that the extracellular matrix protects CSCs during chemotherapy and supports their tumorigenic functions by activating integrin-linked kinase (ILK), a key enzyme in drug resistance. Methods: TCGA datasets and OC models were investigated using an integrated proteomic and gene expression analysis and examined ILK for correlations with chemoresistance pathways and clinical outcomes. Canonical Wnt pathway components, pro-survival signaling, and stemness were examined using OC models. To investigate the role of ILK in the OCSC-phenotype, a novel pharmacological inhibitor of ILK in combination with carboplatin was utilized in vitro and in vivo OC models. Results: In response to increased fibronectin secretion and integrin β1 clustering, aberrant ILK activation supported the OCSC phenotype, contributing to OC spheroid proliferation and reduced response to platinum treatment. Complexes formed by ILK with the Wnt receptor frizzled 7 (Fzd7) were detected in tumors and correlated with metastatic progression. Moreover, TCGA datasets confirmed that combined expression of ILK and Fzd7 in high grade serous ovarian tumors is correlated with reduced response to chemotherapy and poor patient outcomes. Mechanistically, interaction of ILK with Fzd7 increased the response to Wnt ligands, thereby amplifying the stemness-associated Wnt/β-catenin signaling. Notably, preclinical studies showed that the novel ILK inhibitor compound 22 (cpd-22) alone disrupted ILK interaction with Fzd7 and CSC proliferation as spheroids. Furthermore, when combined with carboplatin, this disruption led to sustained AKT inhibition, apoptotic damage in OCSCs and reduced tumorigenicity in mice. Conclusions: This "outside-in" signaling mechanism is potentially actionable, and combined targeting of ILK-Fzd7 may lead to new therapeutic approaches to eradicate OCSCs and improve patient outcomes. [ABSTRACT FROM AUTHOR]

Direct ethanol fuel cell (DEFC) is promising source for mobile and portable applications, but the electrocatalysts are based on metal noble alloys or doping elements to minimize the incomplete ethanol oxidation and poisoning effect. While the main problem persists, this study describes the enhancement of ethanol oxidation reaction by adding graphene (G) to Vulcan XC-72R carbon black (C) metal support, with different C/G ratios. The Graphene was prepared from exfoliated graphite following by dried at ambient temperature. The 60 wt% graphene hybrid support enhances the current density at 5% cyclic voltammetry (CV) and 127% chronoamperometry (CA) higher than carbon pure support in acid electrolyte, whereas in alkaline, graphene (60 wt%) showed the highest electrochemical activity with an increase of current 82% (CV) and 130% (CA). Therefore, we demonstrated the enhancement of the catalyst electrochemical activity in both electrolytes through a simple synthesis method. The 40 wt% carbon and 60 wt% graphene hybrid support achieving higher performance in ethanol oxidation, evidencing a potential application in DEFC. [ABSTRACT FROM AUTHOR]

A series of palladium (II) and platinum (II) selenolate complexes have been isolated depending upon the nature of the phosphine ligand. The substitution reaction of [PdCl2(PPh3)2] with two equivalents of NaSeC5H3(5-Me)N resulted in the hexanuclear complex [Pd6Br0.87Cl1.13{2-SeC5H3(5-Me)N2}2(PPh3)6] (1a) whereas a chelated compound [Pt{κ-Se, κ-N: SeC5H3(5-Me)N}{SeC5H3(5-Me)N}(PPh3)] (1b) has been obtained in the case of [PtCl2(PPh3)2]. However, chelated phosphine as an ancillary ligand with a similar reaction by using [PtCl2(P∩P)] (P∩P = dppm, dppe) yielded cis-configured monomer [Pt{2-SeC5H3(5-Me)N}2(P∩P)]. The trinuclear complexes [M3(µ-Se)3(dppp)3]2+ [M = Pd (2d), Pt (2e)] were isolated by reactions of [MCl2(dppp)] (M = Pd, Pt) with NaSeC5H3(5-Me)N via facile cleavage of Se-C bond in presence of chlorinated solvents. All the synthesized complexes have been characterized by elemental analyses, 1H, 31P{1H}, 77Se{1H} NMR spectroscopy. The molecular structure of complexes [Pd6Br0.87Cl1.13{2-SeC5H3(5-Me)}2(PPh3)6] (1a) and [Pt{2-SeC5H3(5-Me)N}2(dppm)].C6H5CH3 (2a) were determined by single crystal X-ray diffraction analyses. [ABSTRACT FROM AUTHOR]

The rapid fluctuations in heat transfer rates make it challenging to determine the surface temperature history and the estimation of accurate heat generation in research applications such as IC engines, gas turbines, and high-speed space vehicles. Therefore, thin-film heat flux sensors (TFHFS) are generally used to measure the heat flux in such applications due to their high sensitivity and quick response time. The present study demonstrates that increasing the annealing heat treatment temperature will enhance the adhesion of the thin film and the capabilities of these hand-made TFHFS for transient measurements at low temperatures and for short periods. In the present work, TFHFS is fabricated in-house using platinum as a sensing element and Macor as an insulating substrate. The sensitivity (S) and temperature coefficient of resistance (TCR) are estimated using an oil batch calibration technique. At the same time, the performance of TFHFS is tested in a dynamic convective environment. The TFHFS is exposed to the convective environment using a designed calibration set-up, and their transient heat fluxes are computed by conducting several trials. Additionally, the numerical solution has been accomplished using various experimental parameters. In comparison to the outcomes of the experimental method, it is observed that the average fluctuating temperature and mean surface heat flux have an inaccuracy of 0.33% and 4.17% respectively. [ABSTRACT FROM AUTHOR]

Platinum group metals are widely used in the manufacture of advanced materials due to their excellent physical and chemical properties. Especially, palladium (Pd), platinum(Pt), and rhodium(Rh) are used as catalysts for automobiles. In general, combination of pyrometallurgical and hydrometallurgical process is necessary to recover PGMs. In this work, the separation of Pd, Pt, and Rh from the metallic mixture was investigated by selective dissolution using HCl solutions containing oxidizing agents such as H2O2 and NaClO3. As a diluent for the leaching medium, either water or ethylene glycol (EG) was employed and the dissolution behavior of the three metals was compared. Selective dissolution of 99.9% Pd from the metallic mixture was achieved by using 1 M HCl and 1.225 M M H2O2 (H2O medium, 40°C, 30 min), while that of 99.9% Pt was possible by using 5 M HCl and 0.5 M NaClO3 (H2O medium, 60°C,120 min). By these two-step dissolution, Rh metal remained in the residue. A simple process was proposed to separate Pd, Pt, and Rh from their metallic mixture by selective dissolution. [ABSTRACT FROM AUTHOR]

Water purity plays a key role in medical applications such as clinical diagnosis, drug delivery, sterilization, and patient management. One of the most important medical treatments in which the quality of water is very important is hydrotherapy. Most of the patients have weakened immune systems due to existing infections, making them highly vulnerable to new infections from contaminated water in hydrotherapy pools. Therefore, the hydrotherapy water should be tested to ensure the safety of the patients' lives. In this research, a fiber optic bilayer sensor consisting of silver, copper, platinum, nickel, and gold as the metal layer, and scandium oxide as the second layer, has been numerically simulated to test water purity for hydrotherapy applications. The proposed configuration gives water purity detection with a maximum sensitivity of 4594.0°/RIU for Ni/Sc2O3 while the contacting length is considered as 10 mm, which is much higher than the conventional sensor. It is a topic of interest to researchers in related areas. Ag/Sc2O3 exhibits the highest figure of merit value compared to other materials. At the second part of the study, the effect of a silver-aluminum alloy has been investigated to enhance the quality factor of the winner structure (Ag/Sc2O3). The most efficient silver-aluminum combination ratio is found to be 0.1:0.9, which enhances the sensor quality factor from 40.50 to 60.45 (RIU−1) in aqueous media, while the refractive index of water changes from 1.33 to 1.34. [ABSTRACT FROM AUTHOR]

Breast cancer cells have long been inhibited by polypyridine Ru(II) complexes, which are excellent antitumor agents. Due to their multi-targeting properties, this class of ruthenium complexes has received increasing attention as anticancer drug candidates approach to various cellular targets. The aim of this review is to give information about the ligands that were carefully chosen for ruthenium complexes. There has been a great deal of interest in using ruthenium-based complexes to treat breast cancer. Several species have shown potential as treatment candidates. However, further research is needed to determine how these agents affect the metastatic potential of breast cancer cells. The mechanism of action of Ru-based anticancer candidates NAMI-A and KP1019 during phase I clinical trials has been discussed. This article explains hormone-positive breast cancer and triple-negative breast-cancer treatment by using Ru complexes. Although platinum (Pt-based) anticancer medication is widely used in cancer treatment, a minor improvement has been seen and that is Platinum replaced with Ruthenium for its anticancer properties. We have also highlighted the best effective ruthenium-based complexes in treating T.N.B.C. (triple-negative breast cancer) here in this collection. [ABSTRACT FROM AUTHOR]

Background: Platinum-based chemotherapy regimens are a mainstay in the management of ovarian cancer (OC), but emergence of chemoresistance poses a significant clinical challenge. The persistence of ovarian cancer stem cells (OCSCs) at the end of primary treatment contributes to disease recurrence. Here, we hypothesized that the extracellular matrix protects CSCs during chemotherapy and supports their tumorigenic functions by activating integrin-linked kinase (ILK), a key enzyme in drug resistance. Methods: TCGA datasets and OC models were investigated using an integrated proteomic and gene expression analysis and examined ILK for correlations with chemoresistance pathways and clinical outcomes. Canonical Wnt pathway components, pro-survival signaling, and stemness were examined using OC models. To investigate the role of ILK in the OCSC-phenotype, a novel pharmacological inhibitor of ILK in combination with carboplatin was utilized in vitro and in vivo OC models. Results: In response to increased fibronectin secretion and integrin β1 clustering, aberrant ILK activation supported the OCSC phenotype, contributing to OC spheroid proliferation and reduced response to platinum treatment. Complexes formed by ILK with the Wnt receptor frizzled 7 (Fzd7) were detected in tumors and correlated with metastatic progression. Moreover, TCGA datasets confirmed that combined expression of ILK and Fzd7 in high grade serous ovarian tumors is correlated with reduced response to chemotherapy and poor patient outcomes. Mechanistically, interaction of ILK with Fzd7 increased the response to Wnt ligands, thereby amplifying the stemness-associated Wnt/β-catenin signaling. Notably, preclinical studies showed that the novel ILK inhibitor compound 22 (cpd-22) alone disrupted ILK interaction with Fzd7 and CSC proliferation as spheroids. Furthermore, when combined with carboplatin, this disruption led to sustained AKT inhibition, apoptotic damage in OCSCs and reduced tumorigenicity in mice. Conclusions: This "outside-in" signaling mechanism is potentially actionable, and combined targeting of ILK-Fzd7 may lead to new therapeutic approaches to eradicate OCSCs and improve patient outcomes. [ABSTRACT FROM AUTHOR]

The use of nanoparticles has significantly increased in many areas, such as biomedical research, being highly useful as nanoprobes for imaging and as nanocarriers for drug delivery applications. Nevertheless, this potential can only be achieved with the correct characterization of the nanoparticles, since their size and shape can directly affect their biological behavior. In this study, we propose a novel approach for a monolayer deposition of gold and platinum nanoparticles on Si substrates suitable for medium energy ion scattering (MEIS) analysis. The samples were prepared using poly(ethylene glycol) 6000 (PEG 6000) as a coating agent for the substrates, utilizing a spin coater-a versatile, cost-effective, and practical technique. The samples were first analyzed with the RBS technique to assess the adhesion and the overlapping of the nanoparticles in the substrates coated with PEG 6000 and then characterized through the MEIS technique. The analysis through MEIS allowed the determination of the shape, size, and coverage area of the nanoparticles. Scanning and transmission electron microscopy were also performed on the samples, with the results corroborating the findings of the MEIS experiment. Together, the data obtained with microscopy and the MEIS technique suggests the effectiveness of the method in the production of monolayer samples. [ABSTRACT FROM AUTHOR]

Addressing the dual enhancement of circular polarization (glum) and luminescence quantum yield (QY) in circularly polarized luminescence (CPL) systems poses a significant challenge. In this study, we present an innovative strategy utilizing the entropically driven self‐assembly of amphiphilic phosphorescent platinum(II) complexes (L−Pt) with tetraethylene glycol chains, resulting in unique temperature dependencies. The entropically driven self‐assembly of L−Pt leads to a synergistic improvement in phosphorescence emission efficiency (QY was amplified from 15 % at 25 °C to 53 % at 60 °C) and chirality, both in the ground state and the excited state (glum value has been magnified from 0.04×10−2 to 0.06) with increasing temperature. Notably, we observed reversible modulation of phosphorescence and chirality observed over at least 10 cycles through successive heating and cooling, highlighting the intelligent control of luminescence and chiroptical properties by regulating intermolecular interactions among neighboring L−Pt molecules. Importantly, the QY and glum of the L−Pt assembly in solid state were measured as 69 % and 0.16 respectively, representing relatively high values compared to most self‐assembled CPL systems. This study marks the pioneering demonstration of dual thermo‐enhancement of phosphorescence and CPL and provides valuable insights into the thermal effects on high‐temperature and switchable CPL materials. [ABSTRACT FROM AUTHOR]

Addressing the dual enhancement of circular polarization (glum) and luminescence quantum yield (QY) in circularly polarized luminescence (CPL) systems poses a significant challenge. In this study, we present an innovative strategy utilizing the entropically driven self‐assembly of amphiphilic phosphorescent platinum(II) complexes (L−Pt) with tetraethylene glycol chains, resulting in unique temperature dependencies. The entropically driven self‐assembly of L−Pt leads to a synergistic improvement in phosphorescence emission efficiency (QY was amplified from 15 % at 25 °C to 53 % at 60 °C) and chirality, both in the ground state and the excited state (glum value has been magnified from 0.04×10−2 to 0.06) with increasing temperature. Notably, we observed reversible modulation of phosphorescence and chirality observed over at least 10 cycles through successive heating and cooling, highlighting the intelligent control of luminescence and chiroptical properties by regulating intermolecular interactions among neighboring L−Pt molecules. Importantly, the QY and glum of the L−Pt assembly in solid state were measured as 69 % and 0.16 respectively, representing relatively high values compared to most self‐assembled CPL systems. This study marks the pioneering demonstration of dual thermo‐enhancement of phosphorescence and CPL and provides valuable insights into the thermal effects on high‐temperature and switchable CPL materials. [ABSTRACT FROM AUTHOR]

Substrate-controlled product divergence in the reaction of 2-aminopyrimidines with polyfluoroarenes under palladium catalysis is demonstrated for the first time. The reaction of secondary N-alkylpyrimidine-2-amines with polyfluoroarenes leads to C5–H polyfluoroarylation via C–H/C–H coupling, while secondary N-aryl substituents yield N–H polyfluoroarylation, forming triarylamines. [ABSTRACT FROM AUTHOR]

The Ti-MIL-125 metal-organic framework (MOF) functions as a nanoreactor, producing carbon quantum dots (CQDs) within its structure and forming CQD/MOF composites. Similarly, a Pt-CQD/MOF three-component composite is synthesized. Their properties, along with those of CQDs and MOF-free-CQDs (mf -CQDs) enclosed within the MOF, undergo assessment and comparison. Integrating CQDs and Pt minimally alters the MOF structure but reduces specific surface areas due to incorporation. The emitted wavelength of CQD/MOF (570 nm) differs from pristine CQDs (450 nm) and mf -CQDs (496 nm), indicating MOF influence on CQDs' growth and photoluminescence. HOMO and LUMO levels of CQDs/MOF, measured via ultraviolet photoelectron spectroscopy and low-energy inverse photoelectron spectroscopy, are more positive than those of the MOF, suggesting heterogeneous junction formation, aiding electron separation. CQD/MOF exhibits a modest photocatalytic hydrogen evolution rate of 20.4 μmol/g/h. Conversely, Pt-CQD/MOF significantly boosts the rate to 2213 μmol/g/h, underscoring Pt's pivotal catalytic role. [Display omitted] • Ti-MIL-125 MOF functioned as the nanoreactor in the synthesis of CQD. • The MOFs and the CQDs captured inside form the CQD/MOF composites. • The CQDs and those inside MOFs showed different emission wavelengths but similar QY. • Pt particles were incorporated into CQD/MOF for preparing Pt-CQD/MOF composites. • The rate of H 2 generation by Pt-CQD/MOF reached 2213 μ mol h⁻1g⁻1. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations explore the stability of a single platinum atom on various flat, stepped, and defective ceria surfaces, in the context of single‐atom catalysts (SACs) for the water–gas shift (WGS) reaction. The adsorption properties and diffusion kinetics of the metal strongly depend on the support termination with large stability on metastable and stepped CeO2(100) and (210) surfaces where the diffusion of the platinum atom is hindered. At the opposite, the more stable CeO2(111) and (110) terminations weakly bind the platinum atom and can promote the growth of metallic clusters thanks to fast diffusion kinetics. The adsorption of carbon monoxide on the single platinum atom supported on the various ceria terminations is also sensitive to the surface structure. Carbon monoxide weakly binds to the single platinum atom supported on reduced CeO2(111) and (211) terminations. The desorption of the CO2 formed during the WGS reaction is thus facilitated on the latter terminations. A vibrational analysis underlines the significant changes in the calculated scaled anharmonic CO stretching frequency on these catalysts. [ABSTRACT FROM AUTHOR]

Nickel‐based catalysts are recognized as a promising alternative to platinum‐based catalysts for the alkaline hydrogen oxidation reaction (HOR) yet suffer from poor stability and relatively low activity. Herein, a nitrogen ligand‐assisted approach is reported to encapsulate nickel‐copper nanoparticles within few carbon layers, and by modulating the core and shell components/structure, the charge distribution in the nanostructures can be finely regulated. The optimized Ni93Cu7@NC catalyst exhibits outstanding HOR activity with an intrinsic activity of 61.0 µA cm−2 and excellent stability, which is among the most advanced Ni‐based HOR catalysts. Notably, an alkaline exchange membrane fuel cell utilizing this catalyst achieves a peak power density of 381 mW cm−2 and maintains stability at 100 mA cm−2 for over 24 h. Experimental and theoretical investigations unveil that the electron re‐distribution at the interface of NiCu core and nitrogen‐doped carbon reduces the electron occupancy in Ni 4s‐H 1s bonding orbitals and Ni 3dz2/yz‐O 2p antibonding orbitals, leading to a weakened hydrogen binding energy and enhance hydroxide binding energy. Consequently, the limiting energy for the HOR is reduced following a bifunctional mechanism on the Ni93Cu7@NC. This work provides a core‐shell co‐modulation strategy to accurately regulate the electronic structure of transition metals to design robust catalysts. [ABSTRACT FROM AUTHOR]

Iron‐nitrogen‐carbon (Fe‐N‐C) single‐atom catalysts are promising sustainable alternatives to the costly and scarce platinum (Pt) to catalyze the oxygen reduction reactions (ORR) at the cathode of proton exchange membrane fuel cells (PEMFCs). However, Fe‐N‐C cathodes for PEMFC are made thicker than Pt/C ones, in order to compensate for the lower intrinsic ORR activity and site density of Fe‐N‐C materials. The thick electrodes are bound with mass transport issues that limit their performance at high current densities, especially in H2/air PEMFCs. Practical Fe‐N‐C electrodes must combine high intrinsic ORR activity, high site density, and fast mass transport. Herein, it has achieved an improved combination of these properties with a Fe‐N‐C catalyst prepared via a two‐step synthesis approach, constructing first a porous zinc‐nitrogen‐carbon (Zn‐N‐C) substrate, followed by transmetallating Zn by Fe via chemical vapor deposition. A cathode comprising this Fe‐N‐C catalyst has exhibited a maximum power density of 0.53 W cm−2 in H2/air PEMFC at 80 °C. The improved power density is associated with the hierarchical porosity of the Zn‐N‐C substrate of this work, which is achieved by epitaxial growth of ZIF‐8 onto g‐C3N4, leading to a micro‐mesoporous substrate. [ABSTRACT FROM AUTHOR]

The selective oxidation of 5‐(Hydroxymethyl)furfural (HMF) to 2,5‐Furandicarboxylic acid (FDCA) is highly attractive for the production of renewable monomers as substitute for fossil‐based monomers. To achieve a sustainable synthesis, we report on advances for a base‐free approach, reducing waste from the process, using air as oxidant and heterogeneous catalysts. Various Carbon‐based supports, which can be bio‐sourced and cost‐efficient, for Pt particles were investigated as they allow for an easy reuse and at the end‐of‐life Pt can be recycled to enable a closed cycle. Commercially available supports with varying properties, which might replace the base, were studied with Pt particles of similar size and loading. Significant differences in the catalytic activity were observed, which were correlated with the O‐functionalities and graphitization degree of the supports derived from Raman spectroscopy, temperature‐programmed desorption, and X‐ray photoelectron spectroscopy. An activated carbon (Norit ROX) rich in quinone/pyrone‐type groups and a carbon black‐based catalyst with graphene‐layers pushed the efficiency with enhanced FDCA‐yields enabling the complete substitution of the homogeneous base. This allows to circumvent the base in this process which together with high selectivity, air as oxidant, a reusable catalyst, and the use of bio‐based feedstock contributes to the sustainability of the production of renewable monomers. [ABSTRACT FROM AUTHOR]

The decrease in noble metal content presents an efficient approach to attain commercial, effective, and durable electrocatalysts for the hydrogen evolution reaction (HER) at a low fabrication cost. Nonetheless, achieving a proper balance between bimetallic loading ratios and HER performance remains challenging. In this study, a simple and environmentally friendly sonochemical method is employed to successfully synthesize bimetallic palladium–rhodium nanoparticles (Pd‐Rh) with varying ratios, confined within molybdenum disulfide (MoS2) nanosheets. Bimetallic Pd‐Rh/MoS2 composite with different ratios of Pd:Rh is synthesized by adjusting the feed ratio of Pd and Rh precursors (1:4, 1:1, and 4:1). The HER electrocatalytic activity of the bimetallic Pd1‐Rh1/MoS2 composite exhibits the lowest overpotential and a superior Tafel slope, closely rivaling the electrocatalytic activity of the commercial 20 wt% Pt/C. Furthermore, the bimetallic Pd1‐Rh1/MoS2 composite exhibits remarkable stability and durability, with almost negligible performance decay after 2000 cycles. These outstanding HER electrocatalytic properties of the bimetallic composite result from a higher number of active sites, a significantly larger electrochemically active surface area, reduced charge‐transfer resistance, and a larger double‐layer capacitance. These factors collectively facilitate faster adsorption and desorption of hydron on the surface of electrocatalyst. [ABSTRACT FROM AUTHOR]

Hydrolytically stable PdII and PtII complexes supported by acyclic diaminocarbene ligands represent a novel class of structural organometallic anticancer agents exhibiting nanomolar antiproliferative activity in a panel of cancer cell lines (IC50 0.07–0.81 μM) and up to 300‐fold selectivity for cancer cells over normal primary fibroblasts. The lead drug candidate was 300 times more potent than cisplatin in vitro and showed higher efficacy in reducing the growth of aggressive MDA‐MB‐231 xenograft tumors in mice. [ABSTRACT FROM AUTHOR]

Background: Patient-reported outcomes (PROs) are a better tool for evaluating the experiences of patients who have symptomatic, treatment-associated adverse events (AEs) compared with clinician-rated AEs. The authors present PROs assessing health-related quality of life (HRQoL) and treatment-related neurotoxicity for adjuvant capecitabine versus platinum on the Eastern Cooperative Oncology Group-American College of Radiology Imaging Network (ECOG-ACRIN) EA1131 trial (ClinicalTrials.gov identifier NCT02445391). Methods: Participants completed the National Comprehensive Cancer Network Functional Assessment of Cancer Therapy-Breast Cancer Symptom Index (NFBSI-16) and the Functional Assessment of Cancer Therapy-Gynecologic Oncology Group neurotoxicity subscale (platinum arm only) at baseline, cycle 3 day 1 (C3D1), 6 months, and 15 months. Because of early termination, power was insufficient to test the hypothesis that HRQoL, as assessed by the NFBSI-16 treatment side-effect (TSE) subscale, would be better at 6 and 15 months in the capecitabine arm; all analyses were exploratory. Means were compared by using t-tests or the Wilcoxon rank-sum test, and proportions were compared by using the χ2 test. Results: Two hundred ninety-six of 330 eligible patients provided PROs. The mean NFBSI-16 TSE subscale score was lower for the platinum arm at baseline (p = .02; absolute difference, 0.6 points) and for the capecitabine arm at C3D1 (p = .04; absolute difference, 0.5 points), but it did not differ at other times. The mean change in TSE subscale scores differed between the arms from baseline to C3D1 (platinum arm, 0.15; capecitabine arm, -0.72; p = .03), but not from baseline to later time points. The mean decline in Functional Assessment of Cancer Therapy-Gynecologic Oncology Group neurotoxicity subscale scores exceeded the minimal meaningful change (1.38 points) from baseline to each subsequent time point (all p < .05). Conclusions: Despite the similar frequency of clinician-rated AEs, PROs identified greater on-treatment symptom burden with capecitabine and complemented clinician-rated AEs by characterizing patients' experiences during chemotherapy. [ABSTRACT FROM AUTHOR]