Proton diffusion in ceramic fuel cells    陶瓷燃料电池中的质子传导

Ceramic proton conductors are promising electrolyte materials in energy devices such as intermediate temperature solid-oxide fuel cells. However, the fundamental understanding about the relationship between the material structure and the proton transport process is still lacking, eliminating the enhancement of proton conductivity and thus the device performance. We systematically tune the crystal structure and phonon frequency in proton conductors by modulating the lattice strain using high pressure or epitaxial film growth, and study the correlation between crystal structure, lattice vibration and proton conductivity.


Representative publications:

  • P. Du, N. Li, X. Ling, Z. Fan, A. Braun, W. Yang, Q. Chen, A. Yelon, Optimizing the Proton Conductivity with the Isokinetic Temperature in Perovskite-Type Proton Conductors According to Meyer–Neldel Rule, Advanced Energy Materials 12 (2022) 2102939.
  • A. Braun, Q. Chen, Experimental neutron scattering evidence for proton polaron in hydrated metal oxide proton conductors, Nature Communications 8 (2017) 15830.
  • Y. Gao, A.M. Nolan, P. Du, Y. Wu, C. Yang, Q. Chen, Y. Mo, S.-H. Bo, Classical and Emerging Characterization Techniques for Investigation of Ion Transport Mechanisms in Crystalline Fast Ionic Conductors, Chemical Reviews 120 (2020) 5954–6008. (ESI Highly Cited Paper)

Charge carrier transport in perovskite solar cells   钙钛矿太阳能电池的电荷载流子传输

Metal halide perovskites are applied in optoelectronic devices such as solar cells and light-emitting diodes. Despite the intensive research in the past decade, the relation between material and device structure on the charge carrier behavior are still under debate. We investigate the effects of crystal structure, microstructure and device structure on the photogenerated charge carriers and relevant photophysical processes.


Representative publication:

  • Y. Wang, M.-R. Ahmadian-Yazdi, Y. Ni, Y. Jiang, M. Eslamian, Z. Jin, Q. Chen, Boosted Charge-Carrier Transport in Triple-Cation Perovskites by Ultrasonic Vibration Post Treatment, Advanced Electronic Materials (2022) 2101286.
  • C. Yang, P. Du, Z. Dai, H. Li, X. Yang, Q. Chen, Effects of Illumination Direction on the Surface Potential of CH3NH3PbI3 Perovskite Films Probed by Kelvin Probe Force Microscopy, ACS Applied Materials & Interfaces 11 (2019) 14044–14050.

In situ spectroscopic methods for nanoscale material chemistry and physics  材料物理与化学原位光谱表征方法

To investigate the fundamental physical- and chemical-processes in energy materials and devices, we develop and use complementary in situ experimental techniques, including vibrational spectroscopies, X-ray and neutron scattering, and scanning probe microscopies. These microscale probes are combined with conventional electrical and electrochemical characterization of materials at macro-scale. Our novel findings help to design better materials in the future.


Representative publication:

  • Z. Zhao, X. Ling, F. El Gabaly, M. Grass, N. Jabeen, D. Jones, Z. Liu, B.S. Mun, A. Braun, Q. Chen, Observation of Potential-Induced Hydration on the Surface of Ceramic Proton Conductors Using In Situ Near-Ambient Pressure X-ray Photoelectron Spectroscopy, The Journal of Physical Chemistry Letters 13 (2022) 2928–2933.
  • Q. Chen, F. El Gabaly, F. Aksoy Akgul, Z. Liu, B.S. Mun, S. Yamaguchi, A. Braun, Observation of oxygen vacancy filling under water vapor in ceramic proton conductors in situ with ambient pressure XPS, Chemistry of Materials 25 (2013) 4690–4696.