Heterogeneous nanocomposites comprising chemically distinct constituents are particularly promising in electrocatalysis. We herein report a synthetic strategy that combines the reduction of Pt and Co ionic precursors at an appropriate ratio with the subsequent phosphating at an elevated temperature for forming heterogeneous nanocomposites consisting of quasi‐spherical Pt₃Co alloy domains and rod‐like CoP₂ domains for high‐efficiency methanol electro‐oxidation. The strong electronic coupling between Pt₃Co and CoP₂ domains in the nanocomposites render the electron density around Pt atoms to decrease, which is favorable for reducing the adsorption of poisoning CO‐like intermediates on the catalyst surfaces. Accordingly, the as‐prepared heterogeneous Pt₃Co–CoP₂ nanocomposites show good performance for methanol electro‐oxidation both in acidic and alkaline media. In specific, at a Pt loading of only 6.4% on a common carbon substrate, the mass‐based activity of Pt₃Co–CoP₂ nanocomposites in an acidic medium is about 2 and 1.5 times as high as that of commercial Pt/C catalyst (20% mass loading) and home‐made Pt₃Co alloy nanoparticles (8.0% mass loading), while in the alkaline medium, these values are 3 and 2, respectively.

Mastery over the structure of nanoparticles might be an effective way to enhance their performance for a given application. Herein we demonstrate the design of cage-bell nanostructures to enhance the methanol tolerance of platinum (Pt) nanoparticles while remaining their catalytic activity for oxygen reduction reaction. This strategy starts with the synthesis of core-shell-shell nanoparticles with Pt and silver (Ag) residing respectively in the core and inner shell regions, which are then agitated with saturated sodium chloride (NaCl) solution to eliminate the Ag component from the inner shell region, leading to the formation of bimetallic nanoparticles with a cage-bell structure, defined as a movable Pt core enclosed by a metal shell with nano-channels, which exhibit superior methanol-tolerant property in catalyzing oxygen reduction reaction due to the different diffusion behaviour of methanol and oxygen in the porous metal shell of cage-bell structured nanoparticles. In particular, the use of remarkably inexpensive chemical agent (NaCl) to promote the formation of cage-bell structured particles containing a wide spectrum of metal shells highlights its engineering merit to produce highly selective electrocatalysts on a large scale for the cathode reaction of direct methanol fuel cells.

Orthorhombic PdSe₂, cubic Pd₁₇Se₁₅, and monoclinic Pd₇Se₂nanoparticles are precisely synthesized, which show phase-dependent electrocatalysis for the ethanol oxidation reaction.

Nanosized rare earth (RE) hydroxides including La(OH)₃, Nd(OH)₃, Pr(OH)₃, Sm(OH)₃, Gd(OH)₃, and Er(OH)₃ with rod-like morphology are fabricated via a convenient hydrothermal approach. This strategy calls for the first preparation of metal complexes between RE precursors and dodecylamine (DDA) in water/ethanol mixture at room temperature and subsequent thermal decomposition at elevated temperature. The influence of reaction time and water/ethanol volume ratios on the morphology and size of as-prepared RE hydroxides are investigated. CeO₂ nanoparticles with spherical shape could be directly obtained by hydrothermal treatment of complexes formed between Ce precursors and DDA. In addition, by further calcinating the RE hydroxides at high temperature in air, RE oxide nanorods could be readily produced.

The activity of Pt catalysts for the electro-oxidation of methanol can be greatly enhanced by coupling the electron effect with morphological engineering. Herein, we report the use of bimetallic Pt–Co alloys with different molar ratios/morphologies as precursors for P doping to prepare high-efficiency electrocatalysts for the methanol oxidation reaction. We will demonstrate that the P doping could not only change the electron density around Pt atoms, but also significantly alter the original morphology of the alloy precursors. The strong electron affinity of P decreases the electron cloud density around Pt atoms, favorable for weakening the adsorption of poisonous CO-like intermediates and thus enhancing their electrocatalytic activity for methanol oxidation. In particular, the as-prepared ternary Pt₃CoP_n nanoparticles with branched morphologies exhibit a specific activity and mass activity for methanol oxidation of up to 5.62 mA cm⁻² and 1790 mA mg⁻¹, respectively, which are 2.3 and 1.1 times those of ternary Pt₃CoP_n spheres, 4.8 and 1.5 times those of commercial PtRu/C catalysts and surpass those of most Pt-based electrocatalysts reported in the literature. This study thus offers a vivid example to demonstrate the alloying of a transition metal and a non-metal element into active Pt catalysts for improving their electrocatalytic properties.