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 construction of highly active, durable, and cost-effective catalysts is urgently needed for green hydrogen production. Herein, catalysts consisting of high-density Pt (24 atoms nm −2 ) and Ir (32 atoms nm −2 ) sin...
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The construction of highly active, durable, and cost-effective catalysts is urgently needed for green hydrogen production. Herein, catalysts consisting of high-density Pt (24 atoms nm −2 ) and Ir (32 atoms nm −2 ) single atoms anchored on Co(OH) 2 were constructed by a facile one-step approach. Remarkably, Pt 1 /Co(OH) 2 and Ir 1 /Co(OH) 2 only required 4 and 178 mV at 10 mA cm −2 for hydrogen evolution reaction and oxygen evolution reaction, respectively. Moreover, the assembled Pt 1 /Co(OH) 2 //Ir 1 /Co(OH) 2 system showed mass activity of 4.9 A mg noble metal −1 at 2.0 V in an alkaline water electrolyzer, which is 316.1 times higher than that of Pt/C//IrO 2 . Mechanistic studies revealed that reconstructed Ir−O 6 single atoms and remodeled Pt triple-atom sites enhanced the occupancy of Ir−O bonding orbitals and improved the occupation of Pt−H antibonding orbital, respectively, contributing to the formation of the O−O bond and the desorption of hydrogen. This one-step approach was also generalized to fabricate other 20 single-atom catalysts.
An in‐depth understanding of dynamic interfacial self‐assembly processes is essential for a wide range of topics in theoretical physics, materials design, and biomedical research. However, direct monitoring of such ...
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An in‐depth understanding of dynamic interfacial self‐assembly processes is essential for a wide range of topics in theoretical physics, materials design, and biomedical research. However, direct monitoring of such processes is hampered by the poor imaging contrast of a thin interfacial layer. We report in situ imaging technology capable of selectively highlighting self‐assembly at the phase boundary in real time by employing the unique photophysical properties of aggregation‐induced emission. Its application to the study of breath‐figure formation, an immensely useful yet poorly understood phenomenon, provided a mechanistic model supported by direct visualization of all main steps and fully corroborated by simulation and theoretical analysis. This platform is expected to advance the understanding of the dynamic phase‐transition phenomena, offer insights into interfacial biological processes, and guide development of novel self‐assembly technologies.
Correction for ‘Improving the selectivity of hydrogenation and hydrodeoxygenation for vanillin by using vacancy-coupled Ru–N3 single atoms immobilized on defective boron nitride’ by Haoxiang Fan et al., J. Mater. C...
Correction for ‘Improving the selectivity of hydrogenation and hydrodeoxygenation for vanillin by using vacancy-coupled Ru–N3 single atoms immobilized on defective boron nitride’ by Haoxiang Fan et al., J. Mater. Chem. A, 2023, https://***/10.1039/d3ta01384g.
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