A highly active, stable and synergistic Pt nanoparticles/Mo2C nanotube catalyst for methanol electro-oxidation

Abstract

Poor electrocatalytic activity and carbon monoxide (CO) poisoning of the anode in Pt-based catalysts are still two major challenges facing direct methanol fuel cells. Herein, we demonstrate a highly active and stable Pt nanoparticle/Mo 2 C nanotube catalyst for methanol electro-oxidation. Pt nanoparticles were deposited on Mo 2 C nanotubes using a controllable atomic layer deposition (ALD) technique. This catalyst showed much higher catalytic activity for methanol oxidation and superior CO tolerance, when compared with those of the conventional Pt/C and PtRu/C catalysts. The experimental evidence from X-ray absorption near-edge structure spectroscopy and scanning transmission X-ray microscopy clearly support a strong chemical interaction between the Pt nanoparticles and Mo 2 C nanotubes. Our studies show that the existence of Mo 2 C not only minimizes the required Pt usage but also significantly enhances CO tolerance and thus improves their durability. These results provide a promising strategy for the design of highly active next-generation catalysts.

Solvothermal Synthesis of Alloyed PtNi Colloidal Nanocrystal Clusters (CNCs) with Enhanced Catalytic Activity for Methanol Oxidation

“…Meanwhile, compared with PtNi 2 and Pt 2 Ni catalysts, PtNi CNCs show a lower onset potential for MOR, indicating that the oxidation of methanol is much easier to be triggered on the surface of PtNi CNCs. [20] The long term catalytic durability of the catalysts for MOR has been examined by chronoamperometric (CA) meas urements. Figure 5d shows the obtained mass normalized cur rent density-time plots recorded at 0.63 V for 3600 s. It can be observed that the mass current density of PtNi CNCs decreased slowly and it is always higher than those of PtNi 2 and Pt 2 Ni catalysts, further indicating a significantly enhanced electro catalytic durability.…”

Mo2C nanoparticles embedded within bacterial cellulose-derived 3D N-doped carbon nanofiber networks for efficient hydrogen evolution

“…1,2,[4][5][6][7] Among these non-noble-metal HER catalysts, molybdenum carbide (Mo 2 C), which features a d-band electronic structure and catalytic properties similar to those of platinum, has been demonstrated as an active and stable HER catalyst, even in the form of bulky particles. [8][9][10][11][12][13] Previous research has revealed that the coupling of Mo 2 C particles with nanocarbons is an excellent strategy for improving the HER activity, 8,9,[14][15][16] because of the following reasons: (1) carbon supports create a resistanceless path for rapid electron transfer and also effectively inhibit Mo 2 C nanoparticle aggregation; (2) coupling conjugation can downshift the d-band center of molybdenum by inducing a charge transfer from molybdenum to carbon, thus achieving a relatively moderate Mo-H bond strength for enhanced H desorption. 8,15 In particular, if the carbon supports are electrochemically active N-doped nanocarbons, their synergistic effects become more significant.…”

Study of PtPd Bimetallic Nanoparticles for Fuel Cell Applications

“…A solution to enhancement the electrocatalytic properties is to mix the Pt with other elements or deposited on different supports 12 . Among Pt-based catalysts, Pt-Pd is one of the most attractive bimetallic systems due to its application as electrocatalyst in fuel cells [13][14][15] and various applications including hydrogenation [16][17] and oxidation of organic compounds 18 .…”