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1. Sub‐6 nm Fully Ordered L 1 ₀ ‐Pt–Ni–Co Nanoparticles Enhance Oxygen Reduction via Co Doping Induced Ferromagnetism Enhancement and Optimized Surface Strain

   https://doi.org/10.1002/aenm.201803771  

   Wang, Tanyuan; Liang, Jiashun; Zhao, Zhonglong; Li, Shenzhou; Lu, Gang; Xia, Zhengcai; Wang, Chao; Luo, Jiahuan; Han, Jiantao; Ma, Cheng; et al (March 2019, Advanced Energy Materials)

   Abstract Engineering the crystal structure of Pt–M (M = transition metal) nanoalloys to chemically ordered ones has drawn increasing attention in oxygen reduction reaction (ORR) electrocatalysis due to their high resistance against M etching in acid. Although Pt–Ni alloy nanoparticles (NPs) have demonstrated respectable initial ORR activity in acid, their stability remains a big challenge due to the fast etching of Ni. In this work, sub‐6 nm monodisperse chemically orderedL1₀‐Pt–Ni–Co NPs are synthesized for the first time by employing a bifunctional core/shell Pt/NiCoO_xprecursor, which could provide abundant O‐vacancies for facilitated Pt/Ni/Co atom diffusion and prevent NP sintering during thermal annealing. Further, Co doping is found to remarkably enhance the ferromagnetism (room temperature coercivity reaching 2.1 kOe) and the consequent chemical ordering ofL1₀‐Pt–Ni NPs. As a result, the best‐performing carbon supportedL1₀‐PtNi_0.8Co_0.2catalyst reveals a half‐wave potential (E_1/2) of 0.951 V versus reversible hydrogen electrode in 0.1mHClO₄with 23‐times enhancement in mass activity over the commercial Pt/C catalyst along with much improved stability. Density functional theory (DFT) calculations suggest that theL1₀‐PtNi_0.8Co_0.2core could tune the surface strain of the Pt shell toward optimized Pt–O binding energy and facilitated reaction rate, thereby improving the ORR electrocatalysis. 

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2. Visible light-activatable platinum( iv ) prodrugs harnessing CD36 for ovarian cancer therapy

   https://doi.org/10.1039/d3dt01292a  

   Jayawardhana, Amarasooriya M.; Bhandari, Srijana; Kaspi-Kaneti, Ariela W.; Kshetri, Man; Qiu, Zihan; Cheline, May; Shen, Hao; Dunietz, Barry D.; Zheng, Yao-Rong (August 2023, Dalton Transactions)

   Visible light-activatable Pt(iv) prodrugs harness the upregulated CD36 to facilitate cell entry and killing of drug resistant ovarian cancer cells. 

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3. Luminous Type II Short-plateau SN 2023ufx: Asymmetric Explosion of a Partially Stripped Massive Progenitor

   https://doi.org/10.3847/1538-4357/adb0bb  

   Ravi, Aravind P; Valenti, Stefano; Dong_董, Yize 一泽; Hiramatsu, Daichi; Barmentloo, Stan; Jerkstrand, Anders; Bostroem, K Azalee; Pearson, Jeniveve; Shrestha, Manisha; Andrews, Jennifer E; et al (March 2025, The Astrophysical Journal)

   Abstract We present supernova (SN) 2023ufx, a unique Type IIP SN with the shortest known plateau duration (t_PT∼ 47 days), a luminousV-band peak (M_V= −​​​​​​18.42 ± 0.08 mag), and a rapid early decline rate (s1 = 3.47 ± 0.09 mag (50 days)⁻¹). By comparing observed photometry to a hydrodynamic MESA+STELLA model grid, we constrain the progenitor to be a massive red supergiant withM_ZAMS∼ 19–25M_⊙. Independent comparisons with nebular spectral models also suggest an initial He-core mass of ∼6M_⊙, and thus a massive progenitor. For a Type IIP, SN 2023ufx produced an unusually high amount of nickel (⁵⁶Ni) ∼0.14 ± 0.02M_⊙, during the explosion. We find that the short plateau duration in SN 2023ufx can be explained with the presence of a small hydrogen envelope ( $M_{{\mathrm{H}}_{\mathrm{env}}}$∼ 1.2M_⊙), suggesting partial stripping of the progenitor. About ∼0.09M_⊙of circumstellar material through mass loss from late-time stellar evolution of the progenitor is needed to fit the early time (≲10 days) pseudo-bolometric light curve. Nebular line diagnostics of broad and multipeak components of [Oi]λλ6300, 6364, Hα, and [Caii]λλ7291, 7323 suggest that the explosion of SN 2023ufx could be inherently asymmetric, preferentially ejecting material along our line of sight. 

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4. Supramolecular self-sorting predicted by a simple harmonic oscillator model

   https://doi.org/10.1039/D4CC05336B  

   Sacristán-Martín, Adriana; Álvarez-Llorente, Nerea; Masson, Eric; Diez-Varga, Alberto; Barbero, Héctor (November 2024, Chemical Communications)

   The self-sorting process of homobimetallic Pt(ii) terpyridyl acetylide dimers secured by a pair of Cucurbit[8]uril macrocycles with recognition motif mismatch can be quantified using a model comprising two coupled harmonic oscillators. 

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5. Synthetic Approaches to and Structures of Diplatinum Polyynediyl Complexes trans,trans ‐[(C ₆ F ₅ )(R ₃ P) ₂ Pt(C≡C) _n Pt(PR ₃ ) ₂ (C ₆ F ₅ )] With Odd Numbers of Triple Bonds; Avoiding Complicating Ethynediyl Extrusions

   https://doi.org/10.1002/ejic.202400428  

   Dey_Baksi, Sourajit; Weisbach, Nancy; Bhuvanesh, Nattamai; Gladysz, John_A (October 2024, European Journal of Inorganic Chemistry)

   Abstract Reactions oftrans‐(C₆F₅)(p‐tol₃P)₂Pt(C≡C)_nSiEt₃(PtC_2nSi;n=5, 7, 9) and excessPtClin the presence of wetn‐Bu₄N⁺F⁻(to effect protodesilylation) under Sonogashira‐type conditions (CuCl, base, other additives) afford the title compoundsPtC₁₀Pt,PtC₁₄Pt, andPtC₁₈Ptin 42–32 % yields. A four‐fold substitution of the phosphine ligands inPtC₁₀Ptby PEt₃affordsPt'C₁₀Pt’(78 %), and a Sonogashira reaction ofPt'C₂HandPt'ClaffordsPt'C₂Pt’(68 %). The analogous reaction withPtC₂SiandPtClis unsuccessful, presumably for steric reasons. The crystal structures ofPtC₁₀Pt,PtC₁₄Pt,Pt'C₁₀Pt′, andPt'C₂Pt’exhibit a number of interesting trends and features. Certain sp chain extension reactions that lead to or employ the precursorsPtC₁₀Si,PtC₁₂Si,PtC₁₄Si, andPtC₁₈Sisometimes give byproducts derived from C₂loss, and possible origins are discussed. Related phenomena have been reported by others in the course of synthesizing extended conjugated polyynes. 

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