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Abstract Development of high‐performance, low‐cost catalysts for electrochemical water splitting is key to sustainable hydrogen production. Herein, ultrafast synthesis of carbon‐supported ruthenium–copper (RuCu/C) nanocomposites is reported by magnetic induction heating, where the rapid Joule's heating of RuCl₃and CuCl₂at 200 A for 10 s produces Ru–Cl residues‐decorated Ru nanocrystals dispersed on a CuCl_xscaffold, featuring effective Ru to Cu charge transfer. Among the series, the RuCu/C‐3 sample exhibits the best activity in 1 mKOH toward both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), with an overpotential of only −23 and +270 mV to reach 10 mA cm⁻², respectively. When RuCu/C‐3 is used as bifunctional catalysts for electrochemical water splitting, a low cell voltage of 1.53 V is needed to produce 10 mA cm⁻², markedly better than that with a mixture of commercial Pt/C+RuO₂(1.59 V). In situ X‐ray absorption spectroscopy measurements show that the bifunctional activity is due to reduction of the Ru–Cl residues at low electrode potentials that enriches metallic Ru and oxidation at high electrode potentials that facilitates the formation of amorphous RuO_x. These findings highlight the unique potential of MIH in the ultrafast synthesis of high‐performance catalysts for electrochemical water splitting. 

Synergetic interactions between ruthenium and molybdenum oxide weaken H adsorption on ruthenium active sites and hence enhance the electrocatalytic activity towards hydrogen evolution reaction. 

Metal chalcogenide nanoparticles play a vital role in a wide range of applications and are typically stabilized by organic derivatives containing thiol, amine, or carboxyl moieties, where the nonconjugated particle–ligand interfaces limit the electronic interactions between the inorganic cores and organic ligands. Herein, a wet-chemistry method is developed for the facile preparation of stable platinum chalcogenide (S, Se) nanoparticles capped with acetylene derivatives (e.g., 4-ethylphenylacetylene, EPA). The formation of Pt–C≡ conjugated bonds at the nanoparticle interfaces, which is confirmed by optical and X-ray spectroscopic measurements, leads to markedly enhanced electronic interactions between the d electrons of the nanoparticle cores and π electrons of the acetylene moiety, in stark contrast to the mercapto-capped counterparts with only nonconjugated Pt–S– interfacial bonds, as manifested in spectroscopic measurements and density functional theory calculations. This study underscores the significance of conjugated anchoring linkages in the stabilization and functionalization of metal chalcogenides, a unique strategy for diverse applications. 

Hematite (α-Fe 2 O 3 ) is a promising transition metal oxide for various energy conversion and storage applications due to its advantages of low cost, high abundance, and good chemical stability. However, its low carrier mobility and electrical conductivity have hindered the wide application of hematite-based devices. Fundamentally, this is mainly caused by the formation of small polarons, which show conduction through thermally activated hopping. Atomic doping is one of the most promising approaches for improving the electrical conductivity in hematite. However, its impact on the carrier mobility and electrical conductivity of hematite at the atomic level remains to be illusive. In this work, through a kinetic Monte-Carlo sampling approach for diffusion coefficients combined with carrier concentrations computed under charge neutrality conditions, we obtained the electrical conductivity of the doped hematite. We considered the contributions from individual Fe–O layers, given that the in-plane carrier transport dominates. We then studied how different dopants impact the carrier mobility in hematite using Sn, Ti, and Nb as prototypical examples. We found that the carrier mobility change is closely correlated with the local distortion of Fe–Fe pairs, i.e. the more stretched the Fe–Fe pairs are compared to the pristine systems, the lower the carrier mobility will be. Therefore, elements which limit the distortion of Fe–Fe pair distances from pristine are more desired for higher carrier mobility in hematite. The calculated local structure and pair distribution functions of the doped systems have remarkable agreement with the experimental EXAFS measurements on hematite nanowires, which further validates our first-principles predictions. Our work revealed how dopants impact the carrier mobility and electrical conductivity of hematite and provided practical guidelines to experimentalists on the choice of dopants for the optimal electrical conductivity of hematite and the performance of hematite-based devices. 

Sustainable hydrogen gas production is critical for future fuel infrastructure. Here, a series of phosphorous-doped carbon nitride materials were synthesized by thermal annealing of urea and ammonium hexafluorophosphate, and platinum was atomically dispersed within the structural scaffold by thermal refluxing with Zeise's salt forming Pt–N/P/Cl coordination interactions, as manifested in X-ray photoelectron and absorption spectroscopic measurements. The resulting materials were found to exhibit markedly enhanced electrocatalytic activity towards the hydrogen evolution reaction (HER) in acidic media, as compared to the P-free counterpart. This was accounted for by P doping that led to a significantly improved charge carrier density within C 3 N 4 , and the sample with the optimal P content showed an overpotential of only −22 mV to reach the current density of 10 mA cm −2 , lower than that of commercial Pt/C (−26 mV), and a mass activity (7.1 mA μg−1Pt at −70 mV vs. reversible hydrogen electrode) nearly triple that of the latter. Results from the present study highlight the significance of P doping in the manipulation of the electronic structures of metal/carbon nitride nanocomposites for high-performance HER electrocatalysis. 

Carbon nanocomposites based on transition-metal oxides have been attracting extensive attention as cost-effective catalysts towards the oxygen reduction reaction (ORR). However, the activity remains subpar as compared to state-of-the-art platinum catalysts. One way to enhance the ORR performance is to dope a second metal into the nanocomposite to manipulate the electronic structure and hence the interactions with key reaction intermediates. Herein, dual metal (Ru and Fe) and nitrogen codoped carbon (RuFe-NC) nanocomposites were synthesized by controlled pyrolysis of a Fe–Ru–Fe trinuclear complex along with zeolitic imidazolate framework-8. The obtained porous nanocomposites consisted of Ru-doped Fe 2 O 3 nanoparticles embedded within a carbon scaffold, and exhibited an ORR activity in alkaline media rivaling that of commercial Pt/C, which was also markedly better than those of the monometallic counterparts and nanocomposites prepared with a simple mixture of the individual monometallic compound precursors. Structural characterization suggests that the use of the trinuclear complex facilitated the atomic dispersion of ruthenium within the iron oxide nanoparticles and charge transfer between the metal centers led to a high ORR activity. Results from this study suggest that rational design of heteronuclear complexes may be a unique strategy in the structural engineering of carbon-metal nanocomposites for high-performance electrocatalysis.