Morphology engineering has been developed as one of the most widely used strategies for improving the performance of electrocatalysts. However, the harsh reaction conditions and cumbersome reaction steps during the nanomaterials synthesis still limit their industrial applications. Herein, one-dimensional (1D) novel-segmented PtTe porous nanochains (PNCs) were successfully synthesized by the template methods assisted by Pt autocatalytic reduction. The PtTe PNCs consist of consecutive mesoporous architectures that provide a large electrochemical surface area (ECSA) and abundant active sites to enhance methanol oxidation reaction (MOR). Furthermore, 1D nanostructure as a robust sustaining frame can maintain a high mass/charge transfer rate in a long-term durability test. After 2,000 cyclic voltammetry (CV) cycles, the ECSA value of PtTe PNCs remained as high as 44.47 m²·g_Pt^–1, which was much larger than that of commercial Pt/C (3.95 m²·g_Pt^–1). The high catalytic activity and durability of PtTe PNCs are also supported by CO stripping test and density functional theory calculation. This autocatalytic reduction-assisted synthesis provides new insights for designing efficient low-dimensional nanocatalysts.

The morphology manipulation of nanomaterials by ion irradiation builds a way to precisely control physicochemical properties. Under the continuous irradiation of low energy Ga⁺, Ne⁺, and He⁺ ions, an ion compaction effect has been found in hollow FePt nanochains with ultrathin shell that the volumes of the nanochains are gradually compacted by ions. The deep learning algorithm has been successfully applied to automatically and precisely measure average sizes of spheres in hollow FePt nanochains. The compaction under ion irradiation is very fast in the very early period and then proceeds to a slow region. The compaction rates in both regions are linearly fitted and all the values are in the order of 10^–17 to 10^–14 cm²/ion. Ion species and ion current have effect on the compaction rate. For example, the compaction rate of Ga⁺ ions is larger than those of Ne⁺ and He⁺ ions under an identical current, while irradiation with larger current can compact nanochains faster. The ion compaction effect originates from the local shear deformation caused by the interaction between incident ions and the electrons of Fe and Pt atoms in the ultrathin shell. With continuous irradiation, the crystalline clusters of FePt nanchains firstly grow larger and then become amorphous. The ion compaction effect can be applied to tune the size and crystal structure of hollow structures with a precise rate by choosing appropriate ion species and current.

Tunable behavior in electrocatalysis by external multifields, such as magnetic field, thermal field, and electric field, is the most promising strategy to expand the theory, design, and synthesis of state-of-the-art catalysts and the cell in the near future. Here, a systematic investigation for the effect of external magnetic field and thermal field on methanol oxidation reactions (MOR) in magnetic nanoparticles is reported. For Co₄₂Pt₅₈ truncated octahedral nanoparticles (TONPs), the catalytic performance in MOR is greatly increased to the maximum of 14.1% by applying a magnetic field up to 3000 Oe, and it shows a monotonical increase with increasing working temperature. The magnetic enhanced effect is closely related to the Co content of Co_xPt_100-x TONPs. Furthermore, the enhancement effect under a magnetic field is more obvious for Co₄₂Pt₅₈ TONPs annealed at 650 ℃. First-principle calculation points out that the magnetic fields can facilitate the dehydrogenation of both methanol and water by suppression of entropy of the electron spin and lowering of the activation barrier, where OH_ad intermediates on Co sites play a more important role. The application of magnetic fields together with thermal fields in MOR provides a new prospect to manipulate the performance of direct methanol fuel cells, which will accelerate their potential applications.