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The availability of durable, high‐performance electrocatalysts for the hydrogen oxidation reaction (HOR) is currently a constraint for anion‐exchange membrane fuel cells (AEMFCs). Herein, a rapid microwave‐assisted synthesis method is used to develop a core–shell catalyst support based on a hydrogenated TiO₂/carbon for PtRu nanoparticles (NPs). The hydrogenated TiO₂provides a strong metal‐support interaction with the PtRu NPs, which improves the catalyst's oxophilicity and HOR activity compared to commercial PtRu/C and enables greater size control of the catalyst NPs. The as‐synthesized PtRu/TiO₂/C‐400 electrocatalyst exhibits respectable performance in an AEMFC operated at 80 °C, yielding the highest current density (up to 3× higher) within the catalytic region (compared at 0.80–0.90 V) and voltage efficiency (68%@ 0.5 A cm⁻²) values in the compared literature. In addition, the cell demonstrates promising short‐term voltage stability with a minor voltage decay of 1.5 mV h⁻¹. This “first‐of‐its‐kind in alkaline” work may open further research avenues to develop rapid synthesis methods to prepare advanced core–shell metal‐oxide/carbon supports for electrocatalysts for use in the next‐generation of AEMFCs with potential applicability to the broader electrochemical systems research community.

 

Nitrogen doping in carbon materials can modify the employed carbon material’s electronic and structural properties, which helps in creating a stronger metal-support interaction. In this study, the role of nitrogen doping in improving the durability of Pt catalysts supported on a three-dimensional vertically aligned carbon nanofiber (VACNF) array towards oxygen reduction reaction (ORR) was explored. The nitrogen moieties present in the N-VACNF enhanced the metal-support interaction and contributed to a reduction in the Pt particle size from 3.1 nm to 2.3 nm. The Pt/N-VACNF catalyst showed better durability when compared to Pt/VACNF and Pt/C catalysts with similar Pt loading. DFT calculations validated the increase in the durability of the Pt NPs with an increase in pyridinic N and corroborated the molecular ORR pathway for Pt/N-VACNF. Moreover, the Pt/N-VACNF catalyst was found to have excellent tolerance towards methanol crossover. 

This study reports the preparation of a set of hybrid materials consisting of molybdenum disulfide (MoS 2 ) nanopatches on reduced graphene oxide (rGO) nanosheets by microwave specific heating of graphene oxide and molecular molybdenum precursors followed by thermal annealing in 3% H 2 and 97% Ar. The microwave process converts graphene oxide to ordered rGO nanosheets that are sandwiched between uniform thin layers of amorphous molybdenum trisulfide (MoS 3 ). The subsequent thermal annealing converts the intermediate layers into MoS 2 nanopatches with two-dimensional layered structures whose defect density is tunable by controlling the annealing temperature at 250, 325 and 600 °C, respectively. All three MoS 2 /rGO samples and the MoS 3 /rGO intermediate after the microwave step show a high Li-ion intercalation capacity in the initial 10 cycles (over 519 mA h g MoSx −1 , ∼3.1 Li + ions per MoS 2 ) which is attributed to the small MoS 2 nanopatches in the MoS 2 /rGO hybrids while the effect of further S-rich defects is insignificant. In contrast, the Zn-ion storage properties strongly depend on the defects in the MoS 2 nanopatches. The highly defective MoS 2 /rGO hybrid prepared by annealing at 250 °C shows the highest initial Zn-ion storage capacity (∼300 mA h g MoSx −1 ) and close to 100% coulombic efficiency, which is dominated by pseudocapacitive surface reactions at the edges or defects in the MoS 2 nanopatches. The fast fading in the initial cycles can be mitigated by applying higher charge/discharge currents or extended cycles. This study validates that defect engineering is critical for improving Zn-ion storage. 

Nitrogen‐doped graphitic carbon materials have been widely used as a catalyst support in the methanol oxidation reaction (MOR). In this study, we report the role of three‐dimensionally architectured in‐situ N‐doped vertically aligned carbon nanofibers (VACNF) as a catalyst support for MOR in acidic and alkaline media. The abundant graphitic edge sites at the sidewall of N‐doped VACNF strongly anchor the deposited platinum group metal (PGM) catalysts and induce a partial electron transfer between the PGM catalysts and support. Density Functional Theory (DFT) calculations reveal that the strong metal‐support interaction substantially increases the adsorption energy of OH, particularly near the N‐doping sites, which helps to compete and remove the adsorbed intermediate species generated during MOR. The PGM catalysts on N‐doped VACNF support exhibits CO stripping at lower potentials comparing to the commercial Vulcan carbon support and presents an enhanced electrocatalytic performance and better durability for MOR.