AA′-Stacked Trilayer Hexagonal Boron Nitride Membrane for Proton Exchange Membrane Fuel Cells

Abstract

Hexagonal boron nitride (h-BN) and graphene have emerged as promising materials for proton exchange membranes because of their high proton conductivity and chemical stability. However, the defects and grain boundaries generated during the growth and transfer of two-dimensional materials limit their practical applicability. Here, we report the fabrication of membrane electrode assemblies using large-area single-oriented AA′-stacked trilayer h-BN (3L-BN), which exhibits very few defects during the growth and transfer, as a proton exchange membrane for use in fuel cell systems. The fuel cell based on AA′-stacked 3L-BN showed a H 2 permeation current density as low as 2.69 mA cm −2 and an open circuit voltage (OCV) as high as 0.958 V; this performance is much superior to those for cells based on Nafion (3.7 mA cm −2 and 0.942 V, respectively) and single-layer h-BN (10.08 mA cm −2 and 0.894 V, respectively). Furthermore, the fuel cell with the AA′-stacked 3L-BN membrane almost maintained its original performance (OCV, maximum power density, and H 2 permeation current density) even after 100 h of an accelerated stress test at 30% RH and 90 °C, while the fuel cells with the Nafion and single-layer BN membranes exhibited severely deteriorated performances. The stability of the cell based on the AA′-stacked 3L-BN membrane was better because the membrane prevented gas crossover and suppressed the generation of reactive radicals during cell operation.

Synthesis and Modification of Boron Nitride Nanomaterials for Electrochemical Energy Storage: From Theory to Application

“…Although the mechanism of proton transport is not clear, it does not affect the exploration of BN-based PEMFCs. [263][264][265][266] Kim and co-workers constructed a new electrode module and a fuel cell using trilayer h-BN (3L-BN) prepared by the low pressure CVD process (Figure 12d). [263] The characterization confirmed that the h-BN is a large-area single-oriented AA′ stack.…”

“…[263][264][265][266] Kim and co-workers constructed a new electrode module and a fuel cell using trilayer h-BN (3L-BN) prepared by the low pressure CVD process (Figure 12d). [263] The characterization confirmed that the h-BN is a large-area single-oriented AA′ stack. At 10.08 mA cm −2 , the fuel cell with a monolayer BN membrane shows a high hydrogen permeable current density, indicating that gas transboundary flow occurs through the membrane, which may be attributed to intrinsic defects and grain boundaries in the monolayer.…”

“…e) Polarization curves and f) power densities of fuel cells with different membranes. d-f) Reproduced with permission [263]. Copyright 2018, American Chemical Society.…”

Recent Progress on Defect‐rich Transition Metal Oxides and Their Energy‐Related Applications

“…In recent decades, various clean energy conversion devices have been developed rapidly. Lithium ion batteries (LIBs), [2][3][4] solid oxide fuel cells (SOFCs), [5][6][7] proton exchange membrane fuel cells (PEMFCs), [8][9][10] metal-air batteries [11][12][13] and other clean and efficient devices have been continuously studied, fast developed and commercialized. For PEMFCs and metal-air batteries, the oxygen evolution reaction (OER) at the anode and oxygen reduction reaction (ORR) at the cathode are the main reactions of electrochemical conversion.…”

Bi-Functional Composting the Sulfonic Acid Based Proton Exchange Membrane for High Temperature Fuel Cell Application

“…As a primary segment in the hydrogen energy chain, proton-exchange membrane fuel cells (PEMFCs) have also been regard as one of the most promising green energies due to high efficiency and pollution-free properties [8][9][10]. As the core component in a PEMFC, a proton-exchange membrane (PEM) acts as a proton-transporting medium and can directly affect the performance of a PEMFC [11,12]. For numerous developed PEMs, sulfonic acid (SA) groups are the most widely used functional groups due to the great proton conductive efficiency of SA groups with the assistance of water molecules at low temperature [13][14][15].…”