A ZnS/CaZnOS Heterojunction for Efficient Mechanical-to-Optical Energy Conversion by Conduction Band Offset

Dengfeng Peng, Yue Jiang, Bolong Huang (Corresponding Author), Yangyang Du, Jianxiong Zhao, Xin Zhang, Ronghua Ma, Sergii Golovynskyi, Bing Chen, Feng Wang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

22 Citations (Scopus)

Abstract

Actively collecting the mechanical energy by efficient conversion to other forms of energy such as light opens a new possibility of energy-saving, which is of pivotal significance for supplying potential solutions for the present energy crisis. Such energy conversion has shown promising applications in modern sensors, actuators, and energy harvesting. However, the implementation of such technologies is being hindered because most luminescent materials show weak and non-recoverable emissions under mechanical excitation. Herein, a new class of heterojunctioned ZnS/CaZnOS piezophotonic systems is presented, which displays highly reproducible mechanoluminescence (ML) with an unprecedented intensity of over two times higher than that of the widely used commercial ZnS (the state-of-the-art ML material). Density functional theory calculations reveal that the high-performance ML originates from efficient charge transfer and recombination through offset of the valence and conduction bands in the heterojunction interface region. By controlling the ZnS-to-CaZnOS ratio in conjunction with manganese (Mn2+) and lanthanide (Ln3+) doping, tunable ML across the full spectrum is activated by a small mechanical stimulus of 1 N (10 kPa). The findings demonstrate a novel strategy for constructing efficient ML materials by leveraging interface effects and ultimately promoting practical applications for ML.

Original languageEnglish
Article number1907747
JournalAdvanced Materials
Volume32
Issue number16
DOIs
Publication statusPublished - 1 Apr 2020

Keywords

  • doping
  • heterojunctions
  • light emission
  • mechanoluminescence
  • ZnS/CaZnOS

ASJC Scopus subject areas

  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering

Cite this