The efficiency of direct methanol fuel cell (DMFC) is largely determined by the activity and durability of methanol oxidation reaction (MOR) catalysts. Herein, we present a CO-resilient MOR catalyst of palladium-tin n...
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The efficiency of direct methanol fuel cell (DMFC) is largely determined by the activity and durability of methanol oxidation reaction (MOR) catalysts. Herein, we present a CO-resilient MOR catalyst of palladium-tin nano-alloy anchored on Se-doped MXene (PdSn 0.5 /Se−Ti 3 C 2 ) via a progressive one-step electrochemical deposition strategy. MOR mass activity resulting from Pd/Se−Ti 3 C 2 catalyst (1046.2 mA mg −1 ) is over 2-fold larger than that of Pd/Ti 3 C 2 , suggesting that the introduction of Se atoms on MXene might accelerate the reaction kinetics. PdSn 0.5 /Se−Ti 3 C 2 with Se-doping progress of MXene and the cooperated Pd−Sn sites has a superior MOR mass activity (4762.8 mA mg −1 ), outperforming many other reported Pd-based catalysts. Both experimental results and theoretical calculation reveal that boosted electron interaction of metal crystals with Se-doped MXene and optimized distribution of Pd−Sn sites can modulate the d band center, reduce adsorption energies of CO* at Pd site and enhance OH* generation at Sn site, resulting in highly efficient removal of CO intermediates by reaction with neighboring OH species on adjacent Sn sites.
The interplay between chirality with magnetism can break both the space and time inversion symmetry and have wide applications in information storage, photodetectors, multiferroics and spintronics. Herein, we report t...
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The interplay between chirality with magnetism can break both the space and time inversion symmetry and have wide applications in information storage, photodetectors, multiferroics and spintronics. Herein, we report the chiral transition-metal complex cation-based lead halide, R -CDPB and S -CDPB. In contrast with the traditional chiral metal halides with organic cations, a novel strategy for chirality transfer from the transition-metal complex cation to the lead halide framework is developed. The chiral complex cations directly participate the band structure and introduce the d - d transitions and tunable magneto-chiroptical effects in both the ultraviolet and full visible range into R -CDPB and S -CDPB. Most importantly, the coupling between magnetic moment of the complex cation and chiroptical properties is confirmed by the magneto-chiral dichroism. For the band-edge transition, the unprecedented modulation of +514 % for S -CDPB and −474 % for R -CDPB was achieved at −1.3 Tesla. Our findings demonstrate a novel strategy to combine chirality with magnetic moment, and provide a versatile material platform towards magneto-chiroptical and chiro-spintronic applications.
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