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Open Access Research Article Issue
Autocatalytic reduction-assisted synthesis of segmented porous PtTe nanochains for enhancing methanol oxidation reaction
Nano Research Energy 2023, 2: e9120041
Published: 28 November 2022
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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·gPt–1, which was much larger than that of commercial Pt/C (3.95 m2·gPt–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.

Research Article Issue
Ion compaction effect in hollow FePt nanochains with ultrathin shell under low energy ion irradiation
Nano Research 2022, 15(10): 9309-9318
Published: 27 June 2022
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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.

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