About

Xin Sun is an Assistant Professor of Biology at the University of Pennsylvania. His research interests include Computational Biology, Ecology and Biodiversity, Microbiology, and related fields. His work focuses on understanding complex biological systems through computational approaches, contributing to the fields of ecology, microbiology, and biodiversity. As an assistant professor, he is engaged in advancing knowledge in these areas and contributing to the academic community through research and teaching.

Research topics

• Materials science
• Chemical engineering
• Chemistry
• Physical chemistry
• Crystallography
• Computational chemistry
• Photochemistry
• Nanotechnology
• Organic chemistry
• Chemical physics
• Inorganic chemistry

Selected publications

• Uniform lithiophilic layers in 3D current collectors enable ultrastable solid electrolyte interphase for high-performance lithium metal batteries

  Nano Energy · 2022 · 120 citations

  • Materials science
  • Chemical engineering
  DOI

• Supramolecular Self‐Assembled Multi‐Electron‐Acceptor Organic Molecule as High‐Performance Cathode Material for Li‐Ion Batteries

  Advanced Energy Materials · 2021 · 107 citations

  • Materials science
  • Nanotechnology
  • Chemical engineering

  Abstract Organic electrode materials possess many advantages such as low toxicity, sustainability, and chemical/structural tunability toward high energy density. However, to compete with inorganic‐based compounds, crucial aspects such as redox potential, capacity, cycling stability, and electronic conductivity need to be improved. Herein, a comprehensive strategy on the molecular design of small organic electron‐acceptor‐molecule—hexaazatrianthranylene (HATA) embedded quinone (HATAQ) is reported. By introducing conjugated quinone moieties into the electron‐deficient hexaazatriphenylene‐derivative core, HATAQ with highly extended π‐conjugation can yield extra‐high capacity for lithium storage, delivering a capacity of 426 mAh g −1 at 200 mA g −1 (0.4C). At an extremely high rate of 10 A g −1 (19C), a reversible capacity of 209 mAh g −1 corresponding to nearly 85% retention is obtained after 1000 cycles. A unique network of unconventional lock‐and‐key hydrogen bonds in the solid‐state facilitates favorable supramolecular 2D layered arrangement, enhancing cycling stability. To the best of the authors’ knowledge, the capacity and rate capability of HATAQ are found to be the best ever reported for organic small‐molecule‐based cathodes. These results together with density functional theory studies provide proof‐of‐concept that the design strategy is promising for the development of organic electrodes with exceptionally high energy density, rate capability, and cycling stability.

  DOI

• Insights into the Enhanced Cycle and Rate Performances of the F‐Substituted P2‐Type Oxide Cathodes for Sodium‐Ion Batteries

  Advanced Energy Materials · 2020 · 159 citations

  • Materials science
  • Crystallography
  • Chemical engineering

  Abstract A series of F‐substituted Na 2/3 Ni 1/3 Mn 2/3 O 2− x F x ( x = 0, 0.03, 0.05, 0.07) cathode materials have been synthesized and characterized by solid‐state 19 F and 23 Na NMR, X‐ray photoelectron spectroscopy, and neutron diffraction. The underlying charge compensation mechanism is systematically unraveled by X‐ray absorption spectroscopy and electron energy loss spectroscopy (EELS) techniques, revealing partial reduction from Mn 4+ to Mn 3+ upon F‐substitution. It is revealed that not only Ni but also Mn participates in the redox reaction process, which is confirmed for the first time by EELS techniques, contributing to an increase in discharge specific capacity. The detailed structural transformations are also revealed by operando X‐ray diffraction experiments during the intercalation and deintercalation process of Na + , demonstrating that the biphasic reaction is obviously suppressed in the low voltage region via F‐substitution. Hence, the optimized sample with 0.05 mol f.u. −1 fluorine substitution delivers an ultrahigh specific capacity of 61 mAh g −1 at 10 C after 2000 cycles at 30 °C, an extraordinary cycling stability with a capacity retention of 75.6% after 2000 cycles at 10 C and 55 °C, an outstanding full battery performance with 89.5% capacity retention after 300 cycles at 1 C. This research provides a crucial understanding of the influence of F‐substitution on the crystal structure of the P2‐type materials and opens a new avenue for sodium‐ion batteries.

  DOI

Frequent coauthors

• Sheng Dai

  Oak Ridge National Laboratory

  288 shared

• M. Paranthaman

  64 shared

• Craig A. Bridges

  50 shared

• Hailong Lyu

  Oak Ridge National Laboratory

  46 shared

• Bingkun Guo

  Shanghai University

  46 shared

• Charl J. Jafta

  Oak Ridge National Laboratory

  38 shared

• Gabriel M. Veith

  Oak Ridge National Laboratory

  37 shared

• Chen Liao

  Key Laboratory of Guangdong Province

  34 shared

Similar researchers at University of Pennsylvania

• John Q. Trojanowskih-296
• Craig B. Thompsonh-277
• Daniel J Raderh-236
• Carl H. Juneh-218
• M. Celeste Simonh-185