Dongtao Wang

Platinum remains the benchmark catalyst for proton exchange membrane fuel cells, but its long‐term durability and tolerance toward CO impurities are still insufficient for demanding practical operation. Here, we propose a novel perspective to address the degradation and CO‐poisoning of Pt by introducing a quasi‐covalent interaction via trace Nd incorporation into ordered L1 ₂ ‐Pt ₃ Co intermetallic nanoparticles. Our design enables highly robust proton exchange membrane fuel cells (PEMFCs) assembled with L1 ₂ ‐NdPt ₃ Co as the cathode, which achieves a high mass activity (MA) of 1.16 A mgPt ^{− 1} and a peak power density of 1.60 W cm ^{− 2} in H _2– O ₂ mode, as well as an extraordinary durability with a MA retention of 84.86% after 30 000 accelerated durability tests (ADTs), all of which exceed the relevant 2026 DOE targets, due to the Nd‐induced local bonding regulation that strongly restricts metal dissolution and optimizes intermediate adsorption. Moreover, the high current density of 0.34 A cm ^{− 2} at 0.8 V and rated power density of 0.68 W cm ^{− 2} at 0.67 V under realistic H ₂ –air operation suggest the great potential for application of L1 ₂ ‐NdPt ₃ Co in practical heavy‐duty vehicles. This rare‐earth‐induced local bonding regulation provides new perspectives to design highly durable Pt electrocatalysts.

A high level of Fe impurity restricts the sustainable recycling and wide application of recycled aluminum alloys. Optimizing the phase selection to favor less harmful Fe-containing intermetallics is a critical strategy to develop high-performance alloys with high Fe-level contamination. To reveal the intrinsic mechanism of Fe-containing intermetallic transformation in Al-Si-Fe alloys, the thermodynamic stability, thermal properties, elastic properties, and electronic structure evolution of θ-Al₁₃Fe₄, α-Al_7.1Fe₂Si, β-Al₉Fe₂Si_2, and δ-Al₃FeSi₂ phases were systematically investigated by first-principles calculations. The calculated formation energy and binding energy of θ-Al₁₃Fe₄, α-Al_7.1Fe₂Si, β-Al₉Fe₂Si₂ and δ-Al₃FeSi₂ are −0.28 eV/atom, −0.41 eV/atom, −0.57 eV/atom, −1.92 eV/atom and −4.95 eV/atom, −5.14 eV/atom, −5.35 eV/atom and −6.7 eV/atom, respectively. These results revealed that the thermodynamic stability shows an increasing tendency in the sequence of θ-Al₁₃Fe₄, α-Al_7.1Fe₂Si, β-Al₉Fe₂Si₂ and δ-Al₃FeSi₂. The calculated Gibbs free energy, enthalpy, entropy, heat capacity, thermal expansion-temperature, and bulk modulus results demonstrated the increased stability in the sequence of θ-Al₁₃Fe₄, α-Al_7.1Fe₂Si, β-Al₉Fe₂Si₂ and δ-Al₃FeSi₂ phases. These calculated thermal properties validated the phase transformation behaviors. Finally, the enhanced stability and increased modulus values of the δ-Al₃FeSi₂ phase is attributed to the stronger Si-Fe covalent chemical bonding caused by electron transfer. These findings provide new insight for designing recycled aluminum alloys by optimizing Fe-IMC phase selection and transformation pathways.

Microstructural heterogeneity plays an important role in the localized corrosion behavior of aluminum alloys. However, the contribution of fine α-Al(Mn,Fe)Si dispersoids remains insufficiently understood. This study investigates how dispersoid characteristics and Cr, Er, and Zr microalloying relate to localized corrosion in industrial-purity Al-based model alloys. Decreasing the total Mn + Si content increased the average dispersoid size by 146% and reduced the number density by 46%, accompanied by a 77% decrease in corrosion current density and a 411% increase in charge-transfer resistance relative to the base alloy. In the studied alloys, surface and cross-sectional observations together with in situ atomic force microscopy (AFM) were qualitatively consistent with suppression of localized corrosion development. Cr, Er, and Zr microalloying further modified dispersoid characteristics and corrosion response, with Cr producing the greatest improvement in electrochemical resistance. The different responses of the Er- and Zr-containing alloys indicate that dispersoid size and number density alone cannot account for the microalloying effect. A two-level interpretation involving dispersoid/matrix interface density and element-dependent interfacial responses is proposed as a working framework, providing a basis for controlling localized corrosion through dispersoid regulation and microalloying.

Against the backdrop of carbon neutrality targets and resource constraints, the upcycling of recycled aluminum plays a critical role in reducing lifecycle carbon emissions, mitigating dependence on primary aluminum, and expanding the applications of aluminum alloys. In this study, Al–Mg–Si–Cu alloys are fabricated from recycled aluminum beverage can stock, and the influence of Si content (expressed as the Mg/Si ratio) on mechanical properties and intergranular corrosion (IGC) resistance is systematically investigated. Key design guidelines are established. The consumption of Si by Mn, Cr, Fe, and other transition elements forming precipitates must be considered when determining the Mg/Si ratio. When Mg/Si ≤ 1.04, alloys exhibit a yield strength above 394 MPa, tensile strength above 425 MPa, and elongation of at least 8%. IGC susceptibility increases with decreasing Mg/Si. When the Mg/Si ratio is no less than 0.88, the alloy exhibits excellent IGC. The enhanced performance is primarily attributed to the formation of abundant submicron α‐Al(MnFeCr)Si dispersoids, which refine the grains, increase the fraction of low‐angle grain boundaries, and mitigate the detrimental effects of coarse Fe‐rich phases. These findings provide a feasible pathway and quantitative design basis for the high‐value utilization of recycled can‐based aluminum.

The low strength–ductility of cast aluminum alloys is a critical challenge hindering their engineering applications, particularly when the yield strength exceeds 350 MPa, the fracture elongation is only 4 ≈ 5%. In this study, an aging manipulating strategy is designed to achieve increased number density and decreased size of peak‐aged precipitates ( θ ′ and Q″) in high‐strength Al7Si3Cu0.5Mg cast alloy. These manipulated nanoprecipitates improve the strengthening effect and effectively promote homogeneous dislocation distribution during the plastic deformation stage, effectively improving strain hardening and delaying localized failure. The precipitate‐manipulated Al7Si3Cu0.5Mg cast alloy delivers a yield strength of 385 MPa, ultimate tensile strength of 452 MPa, and fracture elongation of 8.1%, achieving almost twofold improvement of ductility while maintaining high strength. This study reveals critical insights into aging‐induced strength–ductility evolution, proposing effective strategies to achieve significant enhancement of ductility in high‐strength cast aluminum alloy.

The process of symmetrical multidirectional pressure was adopted to inhibit the macrosegregation of eutectic Si in squeeze cast A356 alloy. Five pressure modes were applied to study the effects of multidirectional pressure and the timing of pressure application on the macrosegregation of eutectic Si. The results show that the directional movement of the solute-rich liquid phase could be inhibited by symmetrical multidirectional pressure. Therefore, the macrosegregation of eutectic Si in the casting part was inhibited. Moreover, the timing of pressure application should be matched with the local pressure position. After the effective inhibition of the macrosegregation of eutectic Si, the elongation of the alloy was significantly improved, reaching up to 7.12%. In addition, the plastic deformation region was observed at the local pressure position. The grains in the plastic deformation region were refined. The proportion of low-angle grain boundaries in the deformed region was about 30%, which was much higher than that in the other undeformed region. The size of the Fe-containing intermetallics in the deformed region decreased to 5–10 μm, which is favorable for the mechanical properties of the alloy.