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In this work, the adsorption structure of deuterated water on the stepped platinum surface is studied under an ultra-high vacuum by using heterodyne-detected sum-frequency generation spectroscopy. On a pristine Pt(553), D2O molecules adsorbed at the step sites act as hydrogen bond (H-bond) donors to the adjacent terrace sites. This ensures the net D-down orientation at the terrace sites away from the steps. In particular, the pre-adsorption of oxygen atoms at the step sites significantly alters the D-down configuration. The oxygen pre-adsorption leads to a spontaneous dissociation of the post-adsorbed water molecules at the step to form hydroxyl (OD) species. Since the hydroxyl at the step acts as a strong H-bond acceptor, D2O at the terrace no longer maintains the D-down configuration and adopts flat-lying configurations, significantly reducing the number of D-down molecules at the terrace. Density-functional theoretical calculations support these pictures. This work demonstrates the critical role of steps in controlling the net orientation of the interfacial water and provides an important reference for future considerations of the reactions at electrochemical interfaces. [ABSTRACT FROM AUTHOR]

The atomic-level structure of interfaces between Pt and a transition form of Al2O3 were studied using a combination of electron microscopy and first principles calculations. A model system of Pt nanoprecipitates in Al2O3 were formed in sapphire wafers via high-energy ion implantation of Pt followed by thermal annealing at 1000 °C in air. The Pt nanoparticles took the form of tetrahedra and truncated tetrahedra primarily bound by {111}Pt facets. The high prevalence of these facets motivated the development of density functional theory (DFT) based models of (111)Pt interfaces with six different chemical terminations of (2¯01) θ-alumina. The atomic-level structure of the Pt/Al2O3 interfaces was characterized with aberration-corrected scanning transmission electron microscopy (STEM) and the experimental images were compared to STEM image simulations of the DFT models. The model interface with Pt bonded to oxygen-terminated θ-Al2O3, with the Pt located on top of the O and with an underlying layer of octahedral Al, provided the best match to the experimental images. This interfacial termination is also the most stable for the thermal annealing conditions used based on thermodynamic calculations of the interfacial energy as a function of temperature and oxygen partial pressure. This experimentally verified model provides a basis for improving models of Pt/γ-alumina interfaces.

Effective synthesis and application of single-atom catalysts on supports lacking enough defects remain a significant challenge in environmental catalysis. Herein, we present a universal defect-enrichment strategy to increase the surface defects of CeO2-based supports through H2 reduction pretreatment. The Pt catalysts supported by defective CeO2-based supports, including CeO2, CeZrOx, and CeO2/Al2O3 (CA), exhibit much higher Pt dispersion and CO oxidation activity upon reduction activation compared to their counterpart catalysts without defect enrichment. Specifically, Pt is present as embedded single atoms on the CA support with enriched surface defects (CA-HD) based on which the highly active catalyst showing embedded Pt clusters (PtC) with the bottom layer of Pt atoms substituting the Ce cations in the CeO2 surface lattice can be obtained through reduction activation. Embedded PtC can better facilitate CO adsorption and promote O2 activation at PtC-CeO2 interfaces, thereby contributing to the superior low-temperature CO oxidation activity of the Pt/CA-HD catalyst after activation.

Ultrathin ceramic veneers are a viable therapeutic option to manage esthetic challenges in the anterior zone. Proper conditioning of the intaglio surface of porcelain veneers is essential to achieve an adequate bonding. In clinical practice, this is typically done with chemical etching using an acid-containing agent, such as hydrofluoric acid. While it is well established that the etching effect is dependent on etching time and the acid concentration, little is known about the impact of etching time and the veneer fabrication method. The purpose of this pilot study was to evaluate, using scanning electron microscopy (SEM), the effect that different etching-time protocols have on the intaglio surface characteristics of ultrathin ceramic veneers fabricated with either the platinum foil technique or the refractory die technique. Several replicas of an ultrathin feldspathic ceramic veneer for a maxillary central incisor were fabricated. Individual specimens were processed according to different intaglio surface-etching protocols: no etching, etching for 90 seconds, etching for 120 seconds, and etching for 150 seconds (9.6% hydrofluoric acid used for all etching groups). It was observed that the 120-second etching protocol resulted in a favorable microroughness surface pattern in the platinum foil group. This pattern was comparable to that obtained by etching for 90 seconds with hydrofluoric acid the intaglio surface of veneers fabricated with the refractory die technique. Increasing the etching time to 150 seconds did not result in a more favorable roughness pattern. [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]

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]

Isolated platinum(II) ions anchored at acid sites in the pores of zeolite HZSM-5, initially introduced by aqueous ion exchange, were reduced to form platinum nanoparticles that are stably dispersed with a narrow size distribution (1.3 ± 0.4 nm in average diameter). The nanoparticles were confined in reservoirs within the porous zeolite particles, as shown by electron beam tomography and the shape-selective catalysis of alkene hydrogenation. When the nanoparticles were oxidatively fragmented in dry air at elevated temperature, platinum returned to its initial in-pore atomically dispersed state with a charge of +2, as shown previously by X-ray absorption spectroscopy. The results determine the conditions under which platinum is retained within the pores of HZSM-5 particles during redox cycles that are characteristic of the reductive conditions of catalyst operation and the oxidative conditions of catalyst regeneration.

[Display omitted] Transition metal-based nanoparticles (NPs) are emerging as potential alternatives to platinum for catalyzing the oxygen reduction reaction (ORR) in zinc-air batteries (ZAB). However, the simultaneous coexistence of single-atom moieties in the preparation of NPs is inevitable, and the structural complexity of catalysts poses a great challenge to identifying the true active site. Herein, by employing in situ and ex situ XAS analysis, we demonstrate the coexistence of single-atom moieties and iron phosphide NPs in the N, P co-doped porous carbon (in short, Fe-N 4 -Fe 2 P NPs/NPC), and identify that ORR predominantly proceeds via the atomic-dispersed Fe-N 4 sites, while the presence of Fe 2 P NPs exerts an inhibitory effect by decreasing the site utilization and impeding mass transfer of reactants. The single-atom catalyst Fe-N 4 /NPC displays a half-wave potential of 0.873 V, surpassing both Fe-N 4 -Fe 2 P NPs/NPC (0.858 V) and commercial Pt/C (0.842 V) in alkaline condition. In addition, the ZAB based on Fe-N 4 /NPC achieves a peak power density of 140.3 mW cm−2, outperforming that of Pt/C-based ZAB (91.8 mW cm−2) and exhibits excellent long-term stability. This study provides insight into the identification of true active sites of supported ORR catalysts and offers an approach for developing highly efficient, nonprecious metal-based catalysts for high-energy–density metal-air batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Photodynamic therapy (PDT) and catalytic therapy were promising treatment modes, but tumor hypoxia and poor catalytic activity severely limited their efficacies. Herein, using a porphyrin metal–organic framework (PCN-224) as nanocarrier, a platinum/palladium (Pt/Pd) dual-modified PCN-224 nanoprobe (PCN-224-Pt@Pd) with strong peroxidase (POD)/catalase (CAT)-like activities was developed, achieving photothermal-promoted PDT/catalytic therapy. Compared with single ultrasmall Pt modifying, CAT-like activity of Pt/Pd dual-modifying increased oxygen concentration from 6.24 to 9.35 mg/L, which improved singlet oxygen (1O 2) yield from 63.8 % to 82.9 %. Moreover, POD-like activity of Pt/Pd dual-modifying significantly accelerated hydroxyl radicals (·OH) generation. Importantly, PCN-224-Pt@Pd possessed near-infrared II (NIR-II) photothermal effect with a high efficiency (55.6 %), which further promoted ·OH production. Under combined therapy of PCN-224-Pt@Pd, the cell survival rate greatly reduced to 5.8 %, and the tumors were cured, suggesting NIR-II photothermal-enhanced PDT/catalytic therapy. [ABSTRACT FROM AUTHOR]

A selective, sensitive, fast and accurate hydrogen sensor is urgently needed to overcome enormous challenges for enabling safe monitoring and early warning of leaks in applications of hydrogen energy. Metal-oxide semiconductors (MOS) are of great interest as new level of hydrogen sensors because of their high selectivity and sensitivity, in particular, tin dioxide (SnO 2) attracted much attention with superior electrochemical stability and durability. Nevertheless, it is quite challenging to accurately explore nano-scale sensing mechanisms MOS materials by experimental technology. In this work, the effect of Pt-doping on gas sensing mechanisms of SnO 2 is explored via first-principles. The calculated adsorption and electronic properties indicate a significantly stronger adsorption of H 2 on Pt–SnO 2 over the other gases, with breaking of H–H bonds in H 2 , formations of new H–Pt/H–O bonds and obvious changes in electronic structure, and oxygen of Pt–SnO 2 presents large contribution to chemical adsorptions of H 2. The calculated I–V curves suggest that the doping of Pt element results in large compact on conductivity of the system, and dynamic diffusion coefficients at different temperatures demonstrate fast response and superior selectivity of Pt–SnO 2 toward H 2. This work offers conceptual perspective for developing MOS-based gas sensor. [Display omitted] • For the first time, atomic-level hydrogen sensing mechanism of Pt–SnO 2 is studied. • The predicted gas sensing performance of Pt–SnO 2 is consistent with experiment. • Stronger adsorption of H 2 is proved by new bond formation and electronic structure. • Oxygen of Pt–SnO 2 presents large contribution to chemical adsorption of hydrogen. • Doping of Pt leads to significant compact on conductivity of H 2 adsorbed system. [ABSTRACT FROM AUTHOR]

The document is a contents list from the journal CrystEngComm, focusing on the design and understanding of solid-state and crystalline materials. It includes articles on topics such as exploring flexibility in molecular crystals, novel cocrystals of milrinone, and properties of high-temperature piezoelectric crystals. The journal also features papers on chiral resolution, coordination compounds, and the formation of unique crystal structures. The document highlights interdisciplinary research and innovative material innovations in the field of industrial chemistry. [Extracted from the article]

A one-pot method using a dielectric barrier discharge microplasma reactor was employed to rapidly and conveniently prepare glutathione-protected platinum nanoclusters (GSH@PtNCs) with green fluorescence emission. Based on the inner filter effect (IFE), the synthesized GSH@PtNCs were utilized to achieve fast, sensitive and selective detection of malachite green. [ABSTRACT FROM AUTHOR]

Reported herein were two new electrocatalysts based on metal-organic frameworks (MOFs) that were easily crystallized into the pure 3D net. The cobalt (Co-MOF) and iron (Fe-MOF) metal bearing MOFs were prepared with the reaction of cobalt or iron cations with a benzimidazole linker in the mixture of dimethyl formamide (DMF), ethanol, and water using a solvothermal synthesis method. Without any further post-treatments, Co-MOF and Fe-MOF were directly used as promising electrocatalysts for facilitating hydrogen evolution reactions (HER). Remarkably, the high HER catalytic activity was provided through practical measurements with incredible achievement by utilizing Co-MOF and Fe-MOF. The experimental studies showed that both Co-MOF and Fe-MOF coordinated with water molecules and opened access to the metal cation site which facilitated the electrocatalytic activity of them with the lattice water. Both MOFs exhibited superior HER activity including very low overpotentials, low Tafel slopes, high exchange current densities, and long-term stabilities. While the HER overpotential of the GCE/Co-MOF electrode decreased up to 50 mV at a current density of 10 mA/cm2 with a Tafel slope of 38.57 m V. d e c − 1 , Fe-MOF also achieved another incredible overpotential reduction with 46 mV and a Tafel value of 46.71 m V. d e c − 1 , which were very close to the commercial Pt/C electrocatalyst having 42 mV of overpotential with a Tafel slope of about 34.32 m V. d e c − 1 . Additionally, these electrocatalysts showed great current stability with linear sweep voltammetry and good chronoamperometric stability of 86.7% with Fe-MOF and 67.7% with Co-MOF with 12 h tests under stirring for HER. Consequently, this research study represented one of the most successful studies that were done and managed to report one of the best electrocatalytic performances with two simple MOF structures since we managed to break off the limitation for finding available and inexpensive catalysts that were competitive with platinum catalysts that represented the major obstacles (being expensive and rare) that hampered the development of more sophisticated hydrogen production systems. • Iron and cobalt benzimidazole framework electrocatalyst for water-splitting reaction. • Pristine Fe-MOF illustrates excellent electrocatalytic HER activity. • Activity of both Co-MOF and FeMOF are good enough to compete with Pt. • Fe-MOF has 46 mV overpotential with a Tafel value of 46.71 m V. d e c − 1 . [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface partially oxidized Re 3 Co 2 @NCF was synthesized via a hydrothermal followed by pyrolysis strategy. • The Re 3 Co 2 @NCF electrocatalyst exhibited outstanding HER performance and stability in alkaline condition. • The partially oxidized surfaces resulting from the electronic interaction between Re and Co led to the enhanced HER activity. Although the theoretical electrocatalytic activity of rhenium (Re) for the hydrogen evolution reaction is comparable to that of platinum, the experimental performance of reported rhenium-based electrocatalysts remains unsatisfactory. Herein, we report a highly efficient and stable electrocatalyst composed of rhenium and cobalt (Co) nanoalloy embedded in nitrogen-doped carbon film (Re 3 Co 2 @NCF). The Re 3 Co 2 @NCF electrocatalyst exhibited remarkable hydrogen evolution performance, with an overpotential as low as 30 ± 3 mV to reach a current density of 10 mA cm−2. In addition, the Re 3 Co 2 @NCF demonstrated exceptional stability over several days at a current density of 150 mA cm−2. Theoretical calculations revealed that alloying cobalt with rhenium altered the electronic structure of the metals, causing partial oxidation of the superficial metal atoms. This modification provided a balance for various intermediates' adsorption and desorption, thereby boosting the intrinsic activity of rhenium for hydrogen evolution reaction. This work improves the electrocatalytic performance of rhenium to its theoretical activity, suggesting a promising future for rhenium-based electrocatalysts. [ABSTRACT FROM AUTHOR]

With the use of hydrogen as an energy source, mitigation of its leakage in the environment is critical. Therefore, it is required that passive autocatalytic hydrogen–oxygen (H–O) combination systems are developed to combine this hydrogen with oxygen from the air. In the present study, reduced graphene oxide (rGO) sheets loaded with platinum nanoparticles have been developed and studied for their performance as catalysts for hydrogen dissociation as well as its combination with oxygen. The formation of platinum particulates on rGO substrate was confirmed by XRD and SEM. Crystallite sizes of platinum nanoparticles were in the range of 7.8–8.3 nm. However, the platinum particles had spherical morphology with an average particle size of 90 nm when seen through SEM. The particle size distribution was almost similar irrespective of platinum loading. At lower platinum contents, the number density of platinum particles was lower but as the number density of the particles increased with an increase in loading they tended to agglomerate. These platinum-loaded rGO samples were employed as catalysts for hydrogen dissociation kinetic studies using hydrogen deuteride formation as an indicating tool. It was found that the dissociation rate per unit mass improved with an increase in platinum loading up to 11 wt% (Pt11@rGO) and then decreased. When used for (H–O) combination reaction, Pt11@rGO demonstrated the highest combination rates per unit mass of catalyst. Consequently, Pt11@rGO catalyst gave the best performance with regard to the economic use of precious metals for catalytic application. This catalyst may be a potential candidate for traditional as well as futuristic hydrogen mitigation applications. [ABSTRACT FROM AUTHOR]

The substantial promotion of hydrogen evolution reaction (HER) catalytic performance relies on the breakup of the Sabatier principle, which can be achieved by the alternation of the support and electronic metal support interaction (EMSI) is noticed. Due to the utilization of tungsten disulfides as support for platinum (Pt@WS2), surprisingly, Pt@WS2 demands only 31 mV overpotential to attain 10 mA cm−2 in acidic HER test, corresponding to a 2.5‐fold higher mass activity than benchmarked Pt/C. The pH dependent electrochemical measurements associated with H2‐TPD and in situ Raman spectroscopy indicate a hydrogen spillover involved HER mechanism is confirmed. The WS2 support triggers a higher hydrogen binding strength for Pt leading to the increment in hydrogen concentration at Pt sites proved by upshifted d band center as well as lower Gibbs free energy of hydrogen, favourable for hydrogen spillover. Besides, the WS2 shows a comparably lower effect on Gibbs free energy for different Pt layers (−0.50 eV layer−1) than carbon black (−0.88 eV layer−1) contributing to a better Pt utilization. Also, the theoretical calculation suggests the hydrogen spillover occurs on the 3rd Pt layer in Pt@WS2; moreover, the energy barrier is lowered with increment in hydrogen coverage on Pt. Therefore, the boosted HER activity attributes to the EMSI effect caused hydrogen spillover and enhancement in Pt utilization efficiency. [ABSTRACT FROM AUTHOR]

The chemistry of platinum(II) and platinum(IV) with the ligands 3,4,5-tris(2-pyridyl)-4-H-1,2,4-triazole, L1, and 3,5-di(2-pyridyl)-4-(4-pyridyl)-4-H-1,2,4-triazole, L2, is described. The ligand L1 forms platinum(II) complexes [PtXY(κ2-N, N′-L1)] (X, Y = Cl, Cl; Cl, Me; Me, Me) by chelation while ligand L2 forms either analogous chelate complexes [PtXY(κ2-N, N′-L2)] (X, Y = Cl, Me; Me, Me) or acts as a monodentate ligand in forming trans-[PtCl2(SMe2)(κ1-N-L2)], in which only the 4-pyridyl group is coordinated. The electron-rich dimethylplatinum(II) complexes undergo oxidative addition reactions with methyl iodide to give [PtIMe3(κ2-N, N′-L1)], or with dichloromethane to give [PtClMe2(CH2Cl)(κ2-N, N′-L1)] or [PtClMe2(CH2Cl)(κ2-N, N′-L2)], each of which is formed as a mixture of three isomers. Structure determinations of several of these complexes are reported. [ABSTRACT FROM AUTHOR]

The peroxidase-like properties of a graphene oxide/platinum-cobalt nanocomposite and the rapid color development mechanism of 3,3′,5,5′-tetramethylbenzidine (TMB) through the decomposition of ·OH from H2O2 were utilized to prepare a nonlabelled, simple, and sensitive paper-based colorimetric sensor. This sensor allows visualization of the results and instantaneous detection, enabling quantitative measurement of H2O2. The graphene oxide/platinum cobalt composite was synthesized using a two-step procedure. Its properties were investigated using transmission electron microscopy (TEM), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDS). The composite was subsequently transferred onto a paper substrate to create the colorimetric sensor. The optimal catalytic conditions were a composite concentration of 201.17 µg/mL, a color development time of 3 min, a TMB concentration of 2 mmol·L−1, and a pH of 4. Using the optimal conditions, the paper-based colorimetric sensor has a linear range for H2O2 from 1.0 × 10−5 to 0.1 mol·L−1, with a limit of detection of 1.0 × 10−6 mol·L−1 which is comparable or better than comparable methods. This paper-based colorimetric sensor has potential applications for the rapid determination of hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Hydrogen production via water electrolysis offers a promising route to sustainable energy, but the slow kinetics of the hydrogen evolution reaction (HER) demands efficient, cost-effective electrocatalysts to replace noble metals like platinum. We report a novel CuFeO₂/Fe₃O₄ (CD-SF) nanocomposite synthesized via microwave combustion featuring, heterostructure characterized by X-ray diffraction, X-ray photon spectroscopy, FESEM, and HRTEM. Electrochemical tests of CD-SF on nickel foam in 1 M KOH with Pt coil (Pt-CE) and graphite rod (Gr-CE) counter electrodes show outstanding HER catalytic activity. CD-SF(Pt-CE) achieved a low overpotential of 64.6 mV at current density 10 mA cm−2, with an exchange current density of 6.08 mA cm−2, while CD-SF(Gr-CE) reached 94.6 mV at 10 mA cm−2 with an exchange current density of 8.24 mA cm−2, outperforming many non-noble metal catalysts. Both catalysts exhibited high stability over 12 h of continuous hydrogen generation. This study highlights CD-SF's potential for large-scale industrial water splitting applications. Graphical illustration of three-electrode system with a unique heterostructured CuFeO 2 /Fe 3 O 4 electrocatalyst (developed in-situ via., MWC technique) coated on nickel foam as anode with Ag/AgCl as reference electrode and platinum coil/graphite rod as counter electrode showing excellent electrocatalytic activity for hydrogen evolution reaction in alkaline KOH medium. [Display omitted] • Low-cost CuFeO₂/Fe₃O₄ electrocatalyst synthesized via microwave combustion. • Cu–Fe cations offer abundant active sites, high conductivity, and enhanced HER performance. • Electrocatalyst's Overpotential: 64.6 mV (100% iR) outperforming with Pt vs graphite as counter electrodes. • High stability and durability for 12+ hours under high current densities for HER. • Counter electrode selection improves CuFeO₂/Fe₃O₄ performance for HER operation. [ABSTRACT FROM AUTHOR]

Bi- and trimetallic platinum(bipyridine)(dithiolene) complexes involving different organic linkers between the redox active platinum(dithiolene) moieties have been synthesized and studied by electrochemistry and spectroelectrochemistry. Cyclic voltammetry experiments carried out on these multinuclear complexes in dichloromethane using [NBu4][PF6] as the supporting salt show only one oxidation process involving the metallacycles. Nevertheless, spectro-electrochemical studies, carried out under the same conditions, show a different evolution of the spectra during oxidation depending on the position of the metallacycles on the phenyl ring. For instance, only the 1,3-disubtituted (Pt21,3-P) and 1,3,5-trisubstituted (Pt31,3,5-P) complexes show the growth of an absorption band in the NIR region upon oxidation while it was not observed for the other complexes. In contrast, electrochemical studies carried out using the poorly coordinating supporting electrolyte, [Na][B(C6H4(CF3)2)4], indicate sequential oxidation of the redox centers with ΔE values varying according to the nature of the bridge and the distance between metal centers. For all the investigated multinuclear complexes, spectro-electrochemical experiments performed in the presence of [Na][B(C6H4(CF3)2)4] show an absorption band in the NIR region consistent with appreciable electrostatic effects and charge delocalization in the mixed valent intermediates. [ABSTRACT FROM AUTHOR]

Hydrogen fuel cells represent a leading technology in developing green energy targeting net‐zero emissions goals by mid‐century. However, the sluggish kinetics of the oxygen reduction reaction (ORR) have hitherto demanded substantial quantities of expensive platinum (Pt) group metals. Advances in catalyst design, including the controllable fabrication of highly branched morphologies to increase the surface area‐to‐volume ratio, intermixing Pt with more affordable transition metals, and controlling composition, offer solutions that can further enhance activity and reduce expense. In this context, Pt/M (M = Fe, Ni, Co) nanopods and nanodendrites with precise composition control using more affordable starting materials are designed and crafted. The method is highly efficient, taking only 30 min and avoiding the need for high‐pressure equipment, making it highly scalable. These catalysts show superior ORR performance at an electrode loading as low as 0.0022 mgPt cm−2. One, nanodendritic Pt/Ni, achieves a mass activity of 0.55AmgPt−1$ \rm {0.55}\, {A\, mg}_{Pt}^{-1} $ at 0.9 V versus RHE, making it 87 times more efficient in terms of Pt‐content than a commercial 10 wt% Pt/C nanoparticle standard. These findings provide new opportunities for developing next‐generation, cost‐efficient Pt‐based catalysts, by potentially advancing hydrogen fuel cell technology through performance enhancement and addressing cost challenges through catalyst design. [ABSTRACT FROM AUTHOR]

Cisplatin is a platinum‐based chemotherapeutic drug used to treat many types of cancer. The aim of this study was to develop a population pharmacokinetic model that incorporates plasma unbound and bound platinum levels. Cancer patients undergoing their first or second cycle of cisplatin‐containing chemotherapy (n = 33) were prospectively randomized to receive a 5‐hydroxytryptamine (5‐HT3) antagonist (5‐HT3A) antiemetic (ondansetron, granisetron, or palonosetron) followed by blood collection over 10 days. Total and unbound platinum levels were quantified using inductively coupled plasma mass spectrometry. Plasma concentrations of bound and unbound platinum were used to develop a nonlinear mixed‐effect pharmacokinetic model in Phoenix NLME (v8.3, Certara Inc.). A stepwise search was used to screen covariates that influenced pharmacokinetic parameters. A compartment for bound platinum was added to a two‐compartment unbound platinum model to create a combined platinum model. The volume of the central compartment for unbound platinum (V1_u) was significantly impacted by previous cisplatin exposure and the intercompartmental clearance of unbound platinum (CL2_u) was significantly influenced by concomitant lorazepam use. The models also suggested ondansetron‐ and granisetron‐treated subjects had a 331% and 114% increase, respectively, in circulating exposures to unbound platinum than palonosetron‐treated subjects. The results suggest platinum pharmacokinetics are altered by concomitant 5‐HT3A antiemetic use, concomitant lorazepam use, and previous exposure to cisplatin. Ondansetron and granisetron co‐treatment increased unbound platinum exposure compared to palonosetron co‐treatment, suggesting that palonosetron may be a preferred 5‐HT3A to reduce the risk of cisplatin‐induced kidney injury. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Dalton Transactions: An International Journal of Inorganic Chemistry," published by The Royal Society of Chemistry. It includes various articles on topics such as batteries, metal complexes, and anticancer agents. The journal aims to connect the world with the chemical sciences and invest profits back into the chemistry community. The articles cover a range of research areas within inorganic chemistry, showcasing diverse perspectives and contributions to the field. [Extracted from the article]

"CrystEngComm" is a journal focused on solid-state and crystalline materials, published by The Royal Society of Chemistry. The latest issue includes research on topics such as circularly polarized luminescence, infrared nonlinear optical materials, and ammonia adsorbents. The articles cover a range of subjects, including the modification of porous organic polymers, the engineering of copper complexes, and the conversion of ethanol to acetaldehyde. The journal also features research on luminescent coordination polymers, photocatalytic degradation, and chiral enantiomeric pairs with unique properties. [Extracted from the article]