Junction and energy band on novel semiconductor-based fuel cells

Abstract

Fuel cells are highly efficient and green power sources. The typical membrane electrode assembly is necessary for common electrochemical devices. Recent research and development in solid oxide fuel cells have opened up many new opportunities based on the semiconductor or its heterostructure materials. Semiconductor-based fuel cells (SBFCs) realize the fuel cell functionality in a much more straightforward way. This work aims to discuss new strategies and scientific principles of SBFCs by reviewing various novel junction types/interfaces, i.e., bulk and planar p-n junction, Schottky junction, and n-i type interface contact. New designing methodologies of SBFCs from energy band/alignment and built-in electric field (BIEF), which block the internal electronic transport while assisting interfacial superionic transport and subsequently enhance device performance, are comprehensively reviewed. This work highlights the recent advances of SBFCs and provides new methodology and understanding with significant importance for both fundamental and applied R&D on new-generation fuel cell materials and technologies.

A nanoscale perspective on solid oxide and semiconductor membrane fuel cells: materials and technology

“…For instance, bulk p-n heterojunction, planar p-n junction, and Schottky junction have been taken into account as a major factor that leads to built-in-field for charge separation, which can block the electrons from passing internally through the devices and thus evade short circuit risk [20,21,[46][47][48]. Based on these working principles, various junction-based fuel cells and relative technologies have been emerged by means of interface modulation method and energy band engineering [49]. Though the SOFC technology has been advanced over the last two decades, unleashing potential of SOFCs requires more attention to be paid on the operation of the commonly used YSZ electrolyte material which has limited ionic conductivity at lower temperatures.…”

Classification of Solid Oxide Fuel Cells

“…To date, various two- and more-phase composites from materials with different conductivity types have been used for SLFC fabrication. A review of the materials can be found in [ 8 , 45 ]. In particular, ceria–carbonate electrolytes possess H + and O 2− conduction [ 41 , 46 ]; therefore, in Figure 1 d the formation of H 2 O on the cathode side is shown.…”

Layered LiCoO2–LiFeO2 Heterostructure Composite for Semiconductor-Based Fuel Cells

“…Recently, semiconductors are selected to serve as novel electrolytes or key components in SOFCs, particularly in a proposed concept of the semiconductor-based fuel cell (SBFC) technology [ 9 , 10 , 11 , 12 , 13 ]. Analogously to the conventional SOFC, the SBFC technology can realize fuel cell function by converting chemical energy into electrical power.…”

“…The semiconductor–ionic conductor layer in SBFC has been dominantly investigated based on the dual- or multiphase homogeneous composites [ 15 , 16 , 17 , 18 , 19 ]. For example, the typical ionic conductors Gd 3+ - or Sm 3+ -doped ceria (GDC or SDC) are composited with a semiconducting LiNiZn-based oxide as the core component to realize the fuel cell functions [ 10 ]. In this regard, the ion-conducting and semiconducting phases can provide the percolating passageways for ions’ transfer, including O 2− and H + ions, while the electron conduction is suppressed by the formed junction in the semiconductor phase.…”