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1. Strengthening boron carbide through lithium dopant

   https://doi.org/10.1111/jace.16889  

   He, Yi; Shen, Yidi; Tang, Bin; An, Qi (November 2019, Journal of the American Ceramic Society)

   Abstract The high strength of boron carbide (B₄C) is essential in its engineering applications such as wear‐resistance and body armors. Here, by employing density functional theory simulations, we demonstrated that the strength of B₄C can be enhanced by doping lithium to boron‐rich boron carbide (B₁₃C₂) to form r‐LiB₁₃C₂. The bonding analysis on r‐LiB₁₃C₂indicates that the electron counting rule (or Wade's rule) is satisfied in r‐LiB₁₃C₂whose formula can be written as r‐Li⁺(B₁₂)^2‐(CB⁺C). The shear deformation on r‐LiB₁₃C₂indicates that its ideal shear strength is larger than that of B₄C because of the existing of Li dopant. The failure process of r‐LiB₁₃C₂under ideal shear deformation initiates from breaking the icosahedral‐icosahedral B‐B bonds. Then these B atoms react with the middle B in the C‐B‐C chain, resulting in the disintegration of icosahedral clusters and brittle failure. More interesting, the nanotwinned r‐LiB₁₃C₂is even stronger than r‐LiB₁₃C₂because of the directional nature of covalent bonding at the twin boundaries. This suggests that the nanotwinned r‐LiB₁₃C₂has a significant enhanced strength compared to B₄C. Our simulation results illustrate the deformation mechanism of Li‐doped boron carbide and its nanotwinned microstructure. We proposed to improve the strength of boron carbide by doping Li into B₁₃C₂and increasing its twin densities. 

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2. Dopant-Induced Energetic Disorder in Conjugated Polymers: Determinant Roles of Polymer–Dopant Distance and Composite Electronic Structures

   https://doi.org/10.1021/acs.jpcc.3c07197  

   Lu-Díaz, Michael; Duhandžić, Muhamed; Harrity, Simon; Samanta, Subhayan; Akšamija, Zlatan; Venkataraman, Dhandapani (March 2024, The Journal of Physical Chemistry C)
3. Decoupling and Coupling of the Host–Dopant Interaction by Manipulating Dopant Movement in Core/Shell Quantum Dots

   https://doi.org/10.1021/acs.jpclett.0c01861  

   Hofman, Elan; Khammang, Alex; Wright, Joshua T.; Li, Zhi-Jun; McLaughlin, Peter Francis; Davis, Andrew Hunter; Franck, John Mark; Chakraborty, Arindam; Meulenberg, Robert W.; Zheng, Weiwei (August 2020, The Journal of Physical Chemistry Letters)
4. Highly Responsive Plasmon Modulation in Dopant-Segregated Nanocrystals

   https://doi.org/10.1021/acs.nanolett.2c04199  

   Tandon, Bharat; Gibbs, Stephen L.; Dean, Christopher; Milliron, Delia J. (February 2023, Nano Letters)
5. 3,4,5‐Trimethoxy Substitution on an N‐DMBI Dopant with New N‐Type Polymers: Polymer‐Dopant Matching for Improved Conductivity‐Seebeck Coefficient Relationship

   https://doi.org/10.1002/anie.202110505  

   Han, Jinfeng; Chiu, Arlene; Ganley, Connor; McGuiggan, Patty; Thon, Susanna M.; Clancy, Paulette; Katz, Howard E. (November 2021, Angewandte Chemie International Edition)

   Abstract Achieving high electrical conductivity and thermoelectric power factor simultaneously for n‐type organic thermoelectrics is still challenging. By constructing two new acceptor‐acceptor n‐type conjugated polymers with different backbones and introducing the 3,4,5‐trimethoxyphenyl group to form the new n‐type dopant 1,3‐dimethyl‐2‐(3,4,5‐trimethoxyphenyl)‐2,3‐dihydro‐1H‐benzo[d]imidazole (TP‐DMBI), high electrical conductivity of 11 S cm⁻¹and power factor of 32 μW m⁻¹ K⁻²are achieved. Calculations using Density Functional Theory show that TP‐DMBI presents a higher singly occupied molecular orbital (SOMO) energy level of −1.94 eV than that of the common dopant 4‐(1, 3‐dimethyl‐2, 3‐dihydro‐1H‐benzoimidazol‐2‐yl) phenyl) dimethylamine (N‐DMBI) (−2.36 eV), which can result in a larger offset between the SOMO of dopant and lowest unoccupied molecular orbital (LUMO) of n‐type polymers, though that effect may not be dominant in the present work. The doped polymer films exhibit higher Seebeck coefficient and power factor than films using N‐DMBI at the same doping levels or similar electrical conductivity levels. Moreover, TP‐DMBI doped polymer films offer much higher electron mobility of up to 0.53 cm² V⁻¹ s⁻¹than films with N‐DMBI doping, demonstrating the potential of TP‐DMBI, and 3,4,5‐trialkoxy DMBIs more broadly, for high performance n‐type organic thermoelectrics. 

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