Platinum–Tellurium Heterojunction Nanosheet Assemblies for Efficient Direct Formic Acid Electrooxidation Catalysis
Chengyuan Dong, Biao Zhang, Huijun Song, Shiyuan Zhou, Jinyu Ye, Hong‐Gang Liao, Lisha Dong, Xiaoqing Huang, Lingzheng Bu
Abstract
Two-dimensional (2D) heterojunction nanomaterials offer exceptional physicochemical and catalytic properties, thanks to their special spatial electronic structure. However, synthesizing morphologically uniform 2D platinum (Pt)-based metallic nanomaterials with diverse crystalline phases remains a formidable challenge. In this study, we have achieved the successful synthesis of advanced 2D platinum–tellurium heterojunction nanosheet assemblies (Pt x –PtTe 2 HJNSAs, x = 0, 1, 2), seamlessly integrating both trigonal PtTe 2 ( t -PtTe 2 ) and cubic Pt ( c -Pt) phases. By enabling efficient electron transport and leveraging the specific electron density present at the heterojunction, the Pt 2 –PtTe 2 HJNSAs/C demonstrated exceptional formic acid oxidation reaction (FAOR) activity and stability. Specifically, the specific and mass activities reached 8.4 mA cm –2 and 6.1 A mg Pt –1, which are 46.7 and 50.8 times higher than those of commercial Pt/C, respectively. Impressively, aberration-corrected high-angle annular dark field scanning transmission electron microscopy (AC-HAADF-STEM) revealed a closely packed arrangement of atomic layers and a coherent intergrowth heterogeneous structure. Density functional theory (DFT) calculations further indicated that rearrangement of electronic structure occurred on the surface of Pt 2 –PtTe 2 HJNSAs resulting in a more favorable dehydrogenation pathway and excellent CO tolerance, beneficial for performance improvement. This work inspires the targeted exploration of Pt-based nanomaterials through 2D heterostructure design, leading to an important impact on fuel cell catalysis and beyond.