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1. Medium‐Entropy Engineering of Magnetism in Layered Antiferromagnet Cu _x Ni _{2(1‐ x )} Cr _x P ₂ S ₆

   https://doi.org/10.1002/adfm.202418722  

   Upreti, Dinesh; Basnet, Rabindra; Sharma, M M; Chhetri, Santosh Karki; Acharya, Gokul; Nabi, Md_Rafique Un; Sakon, Josh; Benamara, Mourad; Mortazavi, Mansour; Hu, Jin (December 2024, Advanced Functional Materials)

   Abstract Antiferromagnetic van der Waals‐typeM₂P₂X₆compounds provide a versatile material platform for studying 2D magnetism and relevant phenomena. Establishing ferromagnetism in 2D materials is technologically valuable. Though magnetism is generally tunable via a chemical way, it is challenging to induce ferromagnetism with isovalent chalcogen and bimetallic substitutions inM₂P₂X₆. Here, we report co‐substitution of Cu¹⁺and Cr³⁺for Ni²⁺in Ni₂P₂S₆, creating Cu_xNi_2(1‐x)Cr_xP₂S₆medium‐entropy alloys spanning a full substitution range (x= 0 to 1). Such substitution strategy leads to a unique evolution in crystal structure and magnetic phases that are distinct from traditional isovalent bimetallic doping, with Cu and Cr co‐substitution enhancing ferromagnetic correlations and generating a weak ferromagnetic phase in intermediate compositions. This aliovalent substitution strategy offers a universal approach for tuning layered magnetism in antiferromagnetic systems, which along with the potential for light‐matter interaction and high‐temperature ferroelectricity, can enable multifunctional device applications. 

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2. Thermoelectric Properties of p‐ and n‐ type Eu ₅ Sn ₂ As ₆

   https://doi.org/10.1002/zaac.202100386  

   Devlin, Kasey P.; Gomez, Braulio; Kauzlarich, Susan M. (February 2022, Zeitschrift für anorganische und allgemeine Chemie)

   Abstract Eu₅Sn₂As₆is a Zintl phase crystalizing in the orthorhombic space groupPbamwith one‐dimensional chains of corner‐shared SnAs₄tetrahedra running in thec‐direction. Eu₅Sn₂As₆has an impressive room temperature Seebeck of >100 μV/K and < – 100 μV/K at 600 K crossing fromp‐ ton‐type at 650 K. The maximum thermoelectric figure of merit,zT, for Eu₅Sn₂As₆is small (0.075), comparable to that of the Zintl phase Ca₅Al₂Sb₆whose thermoelectric performance was improved by doping Na onto the Ca sites. In this study, we show that the thermoelectric properties of Eu₅Sn₂As₆can be improved by substituting with K or La. The series Eu_5‐xK_xSn₂As₆provides an increase in maximumzTof 0.22 forx=0.15 due to a decrease resistivity while the onset of bipolar conduction systematically increases in temperature. Upon La substitution, Eu_5‐xLa_xSn₂As₆results in a newn‐type Zintl phase across the temperature range of 300–800 K. 

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3. Reinvestigation of the ν ₃ – ν ₆ Coriolis interaction in trifluoroiodomethane

   https://doi.org/10.1039/D4CP02640C  

   Bhujel, Arun; Akter, Salma; Ali, Muhammad Qasim; Park, G Barratt (November 2024, Physical Chemistry Chemical Physics)

   An updated fit to the interacting levelsν₃andν₆of CF₃I has been evaluated in this work. 

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4. Sr(Ag _1−x Li _x ) ₂ Se ₂ and [Sr ₃ Se ₂ ][(Ag _1−x Li _x ) ₂ Se ₂ ] Tunable Direct Band Gap Semiconductors

   https://doi.org/10.1002/anie.202301191  

   Zhou, Xiuquan; Wilfong, Brandon; Chen, Xinglong; Laing, Craig; Pandey, Indra R.; Chen, Ying‐Pin; Chen, Yu‐Sheng; Chung, Duck‐Young; Kanatzidis, Mercouri G. (February 2023, Angewandte Chemie International Edition)

   Abstract Synthesizing solids in molten fluxes enables the rapid diffusion of soluble species at temperatures lower than in solid‐state reactions, leading to crystal formation of kinetically stable compounds. In this study, we demonstrate the effectiveness of mixed hydroxide and halide fluxes in synthesizing complex Sr/Ag/Se in mixed LiOH/LiCl. We have accessed a series of two‐dimensional Sr(Ag_1−xLi_x)₂Se₂layered phases. With increased LiOH/LiCl ratio or reaction temperature, Li partially substituted Ag to form solid solutions of Sr(Ag_1−xLi_x)₂Se₂withxup to 0.45. In addition, a new type of intergrowth compound [Sr₃Se₂][(Ag_1−xLi_x)₂Se₂] was synthesized upon further reaction of Sr(Ag_1−xLi_x)₂Se₂with SrSe. Both Sr(Ag_1−xLi_x)₂Se₂and [Sr₃Se₂][(Ag_1−xLi_x)₂Se₂] exhibit a direct band gap, which increases with increasing Li substitution (x). Therefore, the band gap of Sr(Ag_1−xLi_x)₂Se₂can be precisely tuned via fine‐tuningxthat is controlled by only the flux ratio and temperature. 

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5. Oxygen Incorporation in the Molecular Beam Epitaxy Growth of Sc _x Ga _1−x N and Sc _x Al _1−x N

   https://doi.org/10.1002/pssb.201900612  

   Casamento, Joseph; Xing, Huili Grace; Jena, Debdeep (January 2020, physica status solidi (b))

   Secondary‐ion mass spectrometry (SIMS) is used to determine impurity concentrations of carbon and oxygen in two scandium‐containing nitride semiconductor multilayer heterostructures: Sc_xGa_1−xN/GaN and Sc_xAl_1−xN/AlN grown by molecular beam epitaxy (MBE). In the Sc_xGa_1−xN/GaN heterostructure grown in metal‐rich conditions on GaN–SiC template substrates with Sc contents up to 28 at%, the oxygen concentration is found to be below 1 × 10¹⁹ cm⁻³, with an increase directly correlated with the scandium content. In the Sc_xAl_1−xN–AlN heterostructure grown in nitrogen‐rich conditions on AlN–Al₂O₃template substrates with Sc contents up to 26 at%, the oxygen concentration is found to be between 10¹⁹and 10²¹ cm⁻³, again directly correlated with the Sc content. The increase in oxygen and carbon takes place during the deposition of scandium‐alloyed layers. 

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