Exploiting advanced electrocatalysts for the sluggish oxygen reduction reaction (ORR) of the cathode is greatly crucial for proton-exchange membrane fuel cell (PEMFC) commercial application but still exhibit a significant challenge, especially the stability issues that have drawn attractive attention. Therefore, we introduced a nitrogen-doped carbon layer into the Pt/C surface, which not only prevents aggregation of Pt nanoparticles but also endows the electrocatalyst with enhanced performance without hiding the internal Pt active sites. The accelerated durability tests show an ignorable ORR activity loss (10 mV) in the as-prepared Pt/C@NC-0.06 sample compared to the pristine Pt/C catalyst (37 mV) after 5000 cyclic voltammetry cycles. Furthermore, in comparison to the pristine Pt/C catalyst (0.28 mA cm–2), the as-obtained Pt/C@NC-0.06 sample exhibits 2.32-fold improvement for the specific activity. The enhanced ORR properties of the Pt/C@NC-X catalyst in this work supplies a promising way to facilitate the electrocatalytic performance of catalysts in PEMFCs.

Improving the activity and stability of Pt‐based electrocatalysts is essential for large‐scale commercial applications of fuel cells. The ordered Pt‐based alloy nanomaterials encapsulated by coating have attracted significant attention. Here, we displayed a surface coating strategy to synthesize structurally ordered PtCo alloy catalysts featuring nitrogen‐doped carbon (NC). Experimental results reveal that the sample with appropriate dopamine feeding content shows enhanced oxygen reduction activity and stability, which exhibits a mass activity of 1.36 mA ⋅ mg−1Pt and specific activity of 1.98 mA ⋅ cm−2, superior to those of excessive or low dopamine adding content samples and commercial Pt/C catalyst. The enhanced electrocatalytic performance of this catalyst was attributed to the combined effect including the protection of suitable thickness NC shells, strong electronic interaction and high ordering degree. In this work, the surface coating strategy provides available references to further improve the oxygen reduction performance of PtM alloy catalysts.

The high cost and insufficient performance of Pt catalysts for oxygen reduction reaction (ORR) are considered obstacles to the realization of the widespread application of proton exchange membrane fuel cell...

The designs of efficient and inexpensive Pt-based catalysts for methanol oxidation reaction (MOR) are essential to boost the commercialization of direct methanol fuel cells. Here, the highly catalytic performance PtFe alloys supported on multiwalled carbon nanotubes (MWCNTs) decorating nitrogen-doped carbon (NC) have been successfully prepared via co-engineering of the surface composition and electronic structure. The Pt 1 Fe 3 @NC/MWCNTs catalyst with moderate Fe 3 + feeding content (0.86 mA/mg Pt ) exhibits 2.26-fold enhancement in MOR mass activity compared to pristine Pt/C catalyst (0.38 mA/mg Pt ). Furthermore, the CO oxidation initial potential of Pt 1 Fe 3 @NC/MWCNTs catalyst is lower relative to Pt/C catalyst (0.71 V and 0.80 V). Benefited from the optimal surface compositions, the anti-corrosion ability of MWCNT, strong electron interaction between PtFe alloys and MWCNTs and the N-doped carbon (NC) layer, the Pt 1 Fe 3 @NC/MWCNTs catalyst presents an improved MOR performance and anti-CO poisoning ability. This study would open up new perspective for designing efficient electrocatalysts for the DMFCs field.

The preparation of low-cost, high-activity, and high-stability platinum (Pt)-based oxygen reduction reaction (ORR) catalysts is the key to the large-scale commercial application of proton exchange membrane fuel cells. Herein, we designed a facile synthesis strategy to achieve direct transformation of solid Pt nanoparticles into hollow PtNi alloy nanocubes through a eutectic salt-mediated pyrolysis strategy and nanoscale Kirkendall effect. This distinctive hollow structure makes the inner and exterior spaces easy to access, which would expose additional active sites and a high active surface area. Accordingly, the as-synthesized Pt1Ni8@NC sample, with the moderate Ni feeding content, exhibits an improved ORR activity and stability with respect to a pristine Pt/C catalyst. Such improvement in ORR performance is mainly caused by the moderate surface compositions, high surface area, and well-designed nanostructure. Indeed, this facile surfactant- and template-free synthetic strategy in our work can be extended for fabricating electrocatalysts with a similar hollow cubic structure.