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Thehydrogenoxidationreaction(HOR)inalkalineelectrolytesexhibitsmarkedlyslowerkineticsthanthatinacidic electrolytes.Thisposesacriticalchallengeforalkalineexchangemembranefuelcells(AEMFCs).Theslowerkineticsinalkaline electrolytesisoftenattributedtothemoresluggishVolmerstep(hydrogendesorption).IthasbeenshownthatthealkalineHOR activityonthePtsurfacecanbeconsiderablyenhancedbythepresenceofoxophilictransitionmetals(TMs)andsurface-adsorbed hydroxylgroupsonTMs(TM−OHad),althoughtheexactroleofTM−OHadremainsatopicofactivedebates.Herein,usingsingle- atomRh-tailoredPtnanowiresasamodelsystem,wedemonstratethathydroxylgroupsadsorbedontheRhsites(Rh−OHad)can profoundly reorganize the Pt surface water structure to deliver a record-setting alkaline HOR performance. In situ surface characterizations,togetherwiththeoreticalstudies,revealthatsurfaceRh−OHadcouldpromotetheoxygen-downwater(H2O↓)that favorsmorehydrogenbondwithPtsurfaceadsorbedhydrogen(H2O↓···Had-Pt)thanthehydrogen-downwater(OH2↓).TheH2O↓ furtherservesasthebridgetofacilitatetheformationofanenergeticallyfavorablesix-membered-ringtransitionstructurewith neighboringPt−Had andRh−OHad,thusreducingtheVolmerstepactivationenergyandboostingHORkinetics. 

The performance of electrocatalysts is critical for renewable energy technologies. While the electrocatalytic activity can be modulated through structural and compositional engineering following the Sabatier principle, the insufficiently explored catalyst-electrolyte interface is promising to promote microkinetic processes such as physisorption and desorption. By combining experimental designs and molecular dynamics simulations with explicit solvent in high accuracy, we demonstrated that dimethylformamide can work as an effective surface molecular pump to facilitate the entrapment of oxygen and outflux of water. Dimethylformamide disrupts the interfacial network of hydrogen bonds, leading to enhanced activity of the oxygen reduction reaction by a factor of 2 to 3. This strategy works generally for platinum-alloy catalysts, and we introduce an optimal model PtCuNi catalyst with an unprecedented specific activity of 21.8 ± 2.1 mA/cm²at 0.9 V versus the reversible hydrogen electrode, nearly double the previous record, and an ultrahigh mass activity of 10.7 ± 1.1 A/mg_Pt. 

Ru decorated Ag nanoparticles are designed as highly effective bifunctional electrocatalysts for hydrazine oxidation and hydrogen evolution reactions, enabling a hydrazine assisted water electrolyser with greatly increased current density. 

Electrocatalytic hydrogen evolution reaction (HER) is critical for green hydrogen generation and exhibits distinct pH-dependent kinetics that have been elusive to understand. A molecular-level understanding of the electrochemical interfaces is essential for developing more efficient electrochemical processes. Here we exploit an exclusively surface-specific electrical transport spectroscopy (ETS) approach to probe the Pt-surface water protonation status and experimentally determine the surface hydronium pK a = 4.3. Quantum mechanics (QM) and reactive dynamics using a reactive force field (ReaxFF) molecular dynamics (RMD) calculations confirm the enrichment of hydroniums (H 3 O + * ) near Pt surface and predict a surface hydronium pK a of 2.5 to 4.4, corroborating the experimental results. Importantly, the observed Pt-surface hydronium pK a correlates well with the pH-dependent HER kinetics, with the protonated surface state at lower pH favoring fast Tafel kinetics with a Tafel slope of 30 mV per decade and the deprotonated surface state at higher pH following Volmer-step limited kinetics with a much higher Tafel slope of 120 mV per decade, offering a robust and precise interpretation of the pH-dependent HER kinetics. These insights may help design improved electrocatalysts for renewable energy conversion.