Acta Chimica Sinica ›› 2023, Vol. 81 ›› Issue (10): 1357-1370.DOI: 10.6023/A23050210 Previous Articles     Next Articles

Original article


郑冰*(), 王喆, 何静, 张姣, 戚文博, 张梦圆, 于海涛*()   

  1. 黑龙江大学化学化工与材料学院 功能无机材料化学教育部重点实验室 哈尔滨 150080
  • 投稿日期:2023-05-06 发布日期:2023-06-27
  • 作者简介:
  • 基金资助:
    国家自然科学基金(21601054); 中国博士后科学基金(2020M670935); 黑龙江省省属高校基本科研业务费科研项目(2021-KYYWF0009); 国家大学生创新创业训练计划项目(202210212029); 国家大学生创新创业训练计划项目(2022041); 国家大学生创新创业训练计划项目(202310212033)

Structure and Work Function of Alkaline (Earth) Metal-Bilayer α-Borophene Nanocomposite: A Theoretical Study

Bing Zheng(), Zhe Wang, Jing He, Jiao Zhang, Wenbo Qi, Mengyuan Zhang, Haitao Yu()   

  1. Key Laboratory of Functional Inorganic Material Chemistry (Ministry of Education), School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080
  • Received:2023-05-06 Published:2023-06-27
  • Contact: *E-mail: (B. Zheng); (H. T. Yu)
  • About author:
    The authors contributed equally to this work
  • Supported by:
    National Natural Science Foundation of China(21601054); Project funded by China Postdoctoral Science Foundation(2020M670935); Fundamental Research Funds for the Provincial Universities(2021-KYYWF0009); Training Program of Innovation and Entrepreneurship for Undergraduates of China(202210212029); Training Program of Innovation and Entrepreneurship for Undergraduates of China(2022041); Training Program of Innovation and Entrepreneurship for Undergraduates of China(202310212033)

Work function-adjustable borophene-based electrode materials are of significant importance for achieving the maximum energy conversion efficiency of electronic devices owing to their vital role in efficient transferring of carriers. Accordingly, understanding the regularity in the gradation of the work function for adatom-borophene nanocomposites with diverse adatoms will facilitate the design of such materials. Herein, the structural stabilities, electronic structures, and work functions of M-decorated experimentally available bilayer α-borophene (M/DBBP; M=Li~Cs; Be~Ba) are investigated systematically. The results obtained indicate that M/DBBP are all thermodynamically and kinetically stable. Moreover, M—B bond length, binding energy (Eb), electron transfer between M and DBBP, and work function (ϕ) are linearly dependent on the ionization potential (IP) in the same adatom family for these investigated systems. Furthermore, we report the two exceptional binding energies of Li/DBBP and Be/DBBP, which deviate from abovementioned IP dependence, owing to their extremely small adatoms and the resulting significantly enhanced effective M—B bonding areas. Impressively, the forming interlayer multi-centered B—B bonds lead to a significantly enhanced interlayer interaction of Ca/DBBP relative to other nine M/DBBP systems. In addition to interpreting that the metallic M/DBBP possesses ionic sp-p and dsp-p bonds for M1/DBBP (M1=Li, Na, Be, Mg, Sr, and Ba) and M2/DBBP (M2=K, Rb, Cs, and Ca), respectively, in particular, we confirm that the positive IP dependence of ϕ for alkali (earth) metal/DBBP originates from the synergistic effect of charge rearrangement and the increasing induced dipole moment. Our predictions not only provide guidance to the experimental efforts towards the realization of work function-adjustable borophene-based electrodes, which can be utilized as cathode materials in electronic devices, but also present a rational understanding of the bonding rules between varying alkali (earth) metal adatoms and bilayer α-borophene.

Key words: bilayer borophene, work function, adsorption, electronic structure, binding energy