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Compared to LCTNi cathode, LCTNi-Ce exhibits better electrochemical performance in CO2-SOEC with CO or H2 as the protective gas.

Exploration of highly efficient and stable photocatalysts for water splitting has attracted much attention. However, developing a facile and effective approach to enhance the photocatalytic activity for practical applications is still highly challenging. Herein, we report a newly-fabricated perovskite oxide (Pr0.5(Ba0.5Sr0.5)0.5Co0.8Fe0.2O3) decorated with Au ultrafine nanoparticles for photocatalytic water splitting. An exceptionally high hydrogen evolution rate of 1618 μmol g-1 h-1 was achieved (under 2 h illumination) when the Au mass loading was optimized to 9.3 wt%, which is 540 times higher than that of the pristine one. The splendid photocatalytic activity of the sample was attributed to plasmon-excited hot electron injection from Au to Pr0.5(Ba0.5Sr0.5)0.5Co0.8Fe0.2O3 (PBSCF) under illumination. The finite-difference time-domain simulations (FDTD) demonstrated that the localized strong electric field formed at the interface between Au and PBSCF under illumination, enables the hot electrons to be energetic and make the injection possible.

The scarcity and weak durability of precious metal catalysts are among the biggest obstacles to achieving cost-effective electrocatalysts in fuel cells and metal–air batteries. Hence, it is imperative to develop low-cost non-precious metal catalysts with comparable oxygen reduction reaction (ORR) activity to precious metal catalysts. Herein, we report a highly effective strategy for the facile synthesis of Fe/N-functionalized 3D porous carbon networks. A major advantage of the newly designed catalyst is that ultrafine Fe4N nanoparticles are grown and uniformly mounted on the carbon framework upon pyrolysis treatment at 800 °C, and co-exist with numerous in situ formed Fe–N4 moieties in the carbon matrix, being evidenced by using X-ray absorption and photoelectron spectroscopy. The new electrocatalysts exhibit high ORR activity, comparable/superior to that of the state-of-the-art Fe/N–carbon based catalysts reported to date. Specifically, the catalysts show a half-wave potential of 0.890 V (vs. RHE) and a limited current density of 6.18 mA cm−2. By resorting to experimental measurements and density-functional theory (DFT) calculations, the synergistic effects between Fe–N4 moieties and the Fe4N support are identified for the first time, which play a key role in boosting the catalytic performance of the Fe/N-functionalized porous carbon networks.

Hydrogen, regarded as one of the most promising green and sustainable energy resources, could be generated by splitting water with electrochemical methods. The challenge for efficient hydrogen generation is the sluggish kinetics at the anodes for the oxygen evolution reaction (OER). Here, a novel catalyst with remarkably enhanced OER activity was prepared by coupling FeOOH and NiCoP/C. The enhanced OER activity of the hybrid catalyst should be ascribed to the synergistic effect of the individual components. First, NiCoP/C derived from ZIF-67 with a hollow rhombic dodecahedral architecture not only allows exposure of numerous active sites but also provides high conductivity. Second, the re-localization of electrons at the coupling interface optimizes the adsorption/desorption nature of intermediate oxygenated species and imparts a high OER activity. The hybrid NiCoP/C@FeOOH catalyst exhibits very high OER activity with a low overpotential of 271 mV for producing a current density of 10 mA cm-2 in 1 M KOH aqueous solution, markedly surpassing the individual counterparts of pure NiCoP/C nanocages and bare FeOOH. This work represents a universal strategy for boosting the OER kinetics of catalysts and pushing boundaries for high-efficiency water oxidation.

Because of the advanced nature of their high power density, fast charge/discharge time, excellent cycling stability, and safety, supercapacitors have attracted intensive attention for large-scale applications. Nevertheless, one of the obstacles for their further development is their low energy density caused by sluggish redox reaction kinetics, low electroactive electrode materials, and/or high internal resistance. Here, we develop a facile and simple nitridation process to successfully synthesize hierarchical Ni nanoparticle decorated Ni0.2Mo0.8N nanorod arrays on a nickel foam (Ni–Mo–N NRA/NF) from its NiMoO4 precursor, which delivers a high areal capacity of 2446 mC cm−2 at a current density of 2 mA cm−2 and shows outstanding cycling stability. The superior performance of the Ni–Mo–N NRA/NF can be ascribed to the metallic conductive nature of the Ni–Mo nitride, the fast surface redox reactions for the electrolyte ions and electrode materials, and the low contacted resistance between the active materials and the current collectors. Furthermore, a hybrid supercapacitor (HSC) is assembled using the Ni–Mo–N NRA/NF as the positive electrode and reduced graphene oxide (RGO) as the negative electrode. The optimized HSC exhibits excellent electrochemical performance with a high energy density of 40.9 W h kg−1 at a power density of 773 W kg−1 and a retention of 80.1% specific capacitance after 6000 cycles. These results indicate that the Ni–Mo–N NRA/NF have a promising potential for use in high-performance supercapacitors.

Carbon deposition is a great problem for most solid acid and base catalysts applied in organic catalytic reactions. Basic lithium phosphate catalyst, when used for propylene oxide rearrangement, is also easily deactivated due to carbon deposition. In this paper, a green surface modification technique of steam treatment was employed to suppress carbon deposition on the basic lithium phosphate catalyst and to improve its catalytic performance. The results showed that the catalyst which was pre-treated with steam at 300 °C for 30 minutes exhibited excellent catalytic activity. Furthermore, the amount of carbon deposition was 15.1%, much lower than that of the untreated catalyst (21.5%). The steam treatment could increase the amount of hydroxyl and adjust the distribution of the acid and base sites. The decrease of the amount of Bronsted acid sites resulted in the reduction of carbon deposition. The enhancement of activity could be attributed to the increase of synergistic sites, and this could be due to an increase in the amount of Lewis acid sites and in the strength of the base sites.