Spatial construction of ultrasmall Pt-decorated 3D spinel oxide-modified N-doped graphene nanoarchitectures as high-efficiency methanol oxidation electrocatalysts

Advancements in Noble Metal-Decorated Porous Carbon Nanoarchitectures: Key Catalysts for Direct Liquid Fuel Cells

“…Recently, mixed metal oxides with multiple catalytic functions have been utilized to strengthen the overall performance of noble metal-decorated porous carbon electrocatalysts. 234,235 For instance, our group demonstrated the spatial construction of 3D spinel manganese−cobalt oxidemodified N-doped graphene nanoarchitectures decorated with ultrafine Pt NPs (Pt/MnCo 2 O 4 −NG) using a controllable selfassembly process. 234 As displayed in Figure 17a−f, the 3D cross-linked networks with continuously distributed macropores consisted of numerous doped graphene nanolayers, which facilitated high dispersion of both MnCo 2 O 4 nanocrystals and Pt NPs.…”

“…234,235 For instance, our group demonstrated the spatial construction of 3D spinel manganese−cobalt oxidemodified N-doped graphene nanoarchitectures decorated with ultrafine Pt NPs (Pt/MnCo 2 O 4 −NG) using a controllable selfassembly process. 234 As displayed in Figure 17a−f, the 3D cross-linked networks with continuously distributed macropores consisted of numerous doped graphene nanolayers, which facilitated high dispersion of both MnCo 2 O 4 nanocrystals and Pt NPs. Because of these architectural advantages, the Pt/MnCo 2 O 4 −NG catalyst exhibited exceptional methanoloxidation properties with a high mass activity of 1508.3 mA mg −1 , small Tafel slope of 127 mV dec −1 , and reliable longrange stability (Figure 17g).…”

Durable Electrocatalyst Support Materials Based on N-Doped Mesoporous Carbon Nanofibers with Titanium Nitride Overlay Coating for High-Performance Proton Exchange Membrane Fuel Cells

“…Degradation of carbon under harsh PEMFC conditions is yet to be fully addressed. Electrochemical oxidative corrosion of carbon support due to the high electric fields developed in fuel cells during startup and shutdown cycles and/or insufficient fuel supply results in structural deterioration and metal catalyst (Pt) dissolution, which can severely impede the long-term durability of PEMFCs. − More specifically, at the cathode side, due to the cumulative effect of high potential, moisture, and in some cases, generation of hydrogen peroxide (H 2 O 2 ), the carbon supports suffer from the formation of surface oxides, which eventually leads to the evolution of CO and CO 2 . , The potential range between 0.6 and 1.0 V versus the reversible hydrogen electrode (RHE) thermodynamically favors the carbon oxidation reaction (COR). Further, it has been proposed that the COR can be catalyzed by Pt nanoparticles, most likely via the back-spillover of oxygen-containing surface groups (CO surf ) to the metal surface followed by their oxidation into CO 2 . , Especially, under the harsh working conditions of PEMFCs (e.g., frequent load cycles, high potential, and strong acidic and oxidizing conditions), Pt nanoparticles tend to suffer from dissolution, migration, and Ostwald ripening/coalescence induced by relatively weak interactions/binding between Pt and the carbon support, leading to significant degradation in the overall cell performance. , Therefore, a good catalyst support should possess excellent chemical stability to withstand the oxidative PEMFC environment, high electrical conductivity for rapid electron transfer, unique porous structure for the effective mass transport of reactants/byproducts, large surface area to maximize the catalyst utilization, and strong catalyst–support interactions .…”

Interconnected Pd Nanowire Networks Stereoassembled on Biomass-Derived Porous Carbon Skeletons as Bifunctional Electrocatalysts for Efficient Methanol and Formic Acid Oxidation

“…Over the past few decades, the massive consumption of fossil fuels and deteriorating ecological environment have brought a series of negative impacts on the sustainable development of human society, which highlights the importance of exploring various green energy-generation and -conversion technologies. − Among them, direct methanol fuel cells (DMFCs) and direct formic acid fuel cells (DFAFCs) have been regarded as potential candidates for the next-generation power sources with the merits of high energy transforming efficiency, low greenhouse gas emissions, facile power system integration, suitable operating temperature range, and easy storage and transportation of liquid fuels. − Nonetheless, there are still some obstacles that need to be overcome on the road to the successful commercial application of DMFCs and DFAFCs, including the sluggish anodic reaction kinetics and short service lives. − Given this, the design and construction of advanced anode catalysts are essential to the performance improvement of DMFCs and DFAFCs, which have become a research hotspot in the electrocatalysis field. − …”