Reasonable construction of high activity and selectivity electrocatalysts is crucial to achieve efficient ethanol oxidation reaction (EOR). However, the oxidation of ethanol tends to produce CO species that poison the active centers of the EOR electrocatalysts. Herein, a unique amorphous CrO x -protected defect-rich ultrafine Pd nanowires (CrO x -Pd NWs) is developed. On the one hand, the CrO x layer can act as a protective layer to maintain the structure of the nanowire. On the other hand, it can play the role of OH regulator to optimize the adsorption energy barrier of intermediate species in Pd nanowire, thereby enhancing the ability of the catalyst to resist CO poisoning. The CrO x -Pd NWs exhibit excellent EOR performance with 3.64 times higher mass activity and 50 mV lower CO electro-oxidation potential than commercial Pd black. The results show that the CrO x layer promotes the dissociation of H 2 O into OH ads , while the CrO x transfers electrons to neighboring Pd atoms optimizing the electronic configuration of Pd, thus selectively oxidizing ethanol to acetate and preventing the formation of toxic * CO. This work provides an effective strategy for the synthesis of nanowire materials with oxide/metal interfaces and offers new ideas for the design of catalysts that can efficiently drive EOR.
Jiao Ma,Chengcheng Yang,Shu Zhu,Jinyi Song,Yingzi Fu
In this paper, a simple stereoselective sensing platform for the recognition of ascorbic acid (AA) and isoascorbic acid (IAA) was fabricated via immobilizing HS-β-cyclodextrin (HS-β-CD) on the surface of nanocomposite modified glassy carbon electrodes (GCEs). The nanocomposites were prepared using Pt and Pd bimetal nanowires (Pt–PdNWs) and reduced graphene oxide (rGO). The preparation process was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). After the modified electrodes interacted with the analytes, obvious differences in the peak currents of AA and IAA were obtained, hinting at the ability of the proposed sensor to recognize AA and IAA. This sensor with simple preparation, a rapid response, and excellent stability and reproducibility provided a promising perspective to recognize and determine AA and IAA.