fig1
![Recent advancement of solid oxide fuel cells towards semiconductor membrane fuel cells](https://image.oaes.cc/b769612f-5790-42fe-aa9a-c5948257ae59/em4054.fig.1.jpg)
Figure 1. Schematic representation of different kinds of fuel cells: (A) conventional solid oxide fuel cells (SOFCs). (B) double-layer fuel cells (DLFCs), (C) single component fuel cells (SCFCs), (D) SCFC–nano redox fuel cells, (E) band alignment for SCFCs. Adapted and modified from Ref.[32].