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Abstract Direct ethanol fuel cells have been widely investigated as nontoxic and low-corrosive energy conversion devices with high energy and power densities. It is still challenging to develop high-activity and durable catalysts for a complete ethanol oxidation reaction on the anode and accelerated oxygen reduction reaction on the cathode. The materials’ physics and chemistry at the catalytic interface play a vital role in determining the overall performance of the catalysts. Herein, we propose a Pd/Co@N-C catalyst that can be used as a model system to study the synergism and engineering at the solid-solid interface. Particularly, the transformation of amorphous carbon to highly graphitic carbon promoted by cobalt nanoparticles helps achieve the spatial confinement effect, which prevents structural degradation of the catalysts. The strong catalyst-support and electronic effects at the interface between palladium and Co@N-C endow the electron-deficient state of palladium, which enhances the electron transfer and improved activity/durability. The Pd/Co@N-C delivers a maximum power density of 438 mW cm −2 in direct ethanol fuel cells and can be operated stably for more than 1000 hours. This work presents a strategy for the ingenious catalyst structural design that will promote the development of fuel cells and other sustainable energy-related technologies. 

Atmospheric nitrogen fixation using a photocatalytic system is a promising approach to produce ammonia. However, most of the recently explored photocatalysts for N 2 fixation are in the powder form, suffering from agglomeration and difficulty in the collection and leading to unsatisfactory conversion efficiency. Developing efficient film catalysts for N 2 photofixation under ambient conditions remains challenging. Herein, we report the efficient photofixation of N 2 over a periodic WS 2 @TiO 2 nanoporous film, which is fabricated through a facile method that combines anodization, E-beam evaporation, and chemical vapor deposition (CVD). Oxygen vacancies are introduced into TiO 2 nanoporous films through Ar annealing treatment, which plays a vital role in N 2 adsorption and activation. The periodic WS 2 @TiO 2 nanoporous film with an optimized WS 2 content shows highly efficient photocatalytic performance for N 2 fixation with an NH 3 evolution rate of 1.39 mmol g −1 h −1 , representing one of the state-of-the-art catalysts. 

The structural, thermal, electrical and mechanical properties of fully dense B4C ceramics, sintered using Spark Plasma Sintering (SPS), were studied and compared to the properties of B4C ceramics previously published in the literature. New results on B4C’s mechanical responses were obtained by nanoindentation and ring-on-ring biaxial strength testing. The findings contribute to a more complete knowledge of the properties of B4C ceramics, an important material in many industrial applications.