Feng Yingliang, Zhang Sifan, Chen Mingzhi, Zhu Lihua, Pei An, Wu Fengshun, Liao Xianping, Gao Qingsheng, Wang Weizhen, Yang Zhiqing, Ye Hengqiang, Chen Bing Hui
Jiangxi Province Key Laboratory of Functional Crystalline Materials Chemistry, College of Chemistry and Chemical Engineering, Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou 341000, Jiang Xi, China.
Jiangxi Province Key Laboratory of Functional Crystalline Materials Chemistry, College of Chemistry and Chemical Engineering, Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou 341000, Jiang Xi, China.
J Colloid Interface Sci. 2025 Feb;679(Pt B):918-928. doi: 10.1016/j.jcis.2024.10.136. Epub 2024 Oct 24.
The development of clean energy solutions, such as fuel cells and hydrogen energy, is crucial for addressing the global energy shortage. Platinum (Pt)-based catalysts are widely used in fuel cells and hydrogen energy generation (for example, via water electrolysis). However, reducing the amount of Pt used while maintaining the catalytic performance of such catalysts is essential. Herein, PtLa catalysts (PtLa/C) doped with rare earth element lanthanum (La) with different Pt/La atomic ratios were synthesized using a simple chemical reduction method, resulting in PtLa/C, PtLa/C, PtLa/C, and Pt/C. These PtLa/C catalysts exhibited excellent electrocatalytic activity and stability in methanol oxidation reaction (MOR), hydrogen evolution reaction (HER), and their coupling reaction as MOR||HER under alkaline conditions. The mechanism by which La doping enhances the electrocatalytic properties and stability of Pt-based catalysts was investigated using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), aberration-corrected scanning transmission electron microscopy (AC-STEM), in-situ Fourier transform infrared (FTIR) and operando Raman spectroscopy. For HER, La doping facilitated the adsorption and activation of HO at Pt sites, improving water dissociation and *OH desorption and reducing Pt poisoning by *OH. This enhances both the catalytic performance and stability of PtLa/C for HER. PtLa/C exhibited a considerably lower overpotential of only 111 mV at 100 mA cm compared to commercial 20 wt% Pt/C (Pt/C-Johnson Matthey (JM)), which requires 153 mV. For MOR, La promotes CO bond cleavage and reduces CO adsorption at the Pt sites, thereby enhancing both the performance and stability of the catalysts. The mass activity (MA) of PtLa/C for MOR is 4.44 A mg, which is 12.33 times higher than that of Pt/C-JM (0.36 A/mg), and surpasses those of PtLa/C, PtLa/C, and Pt/C (2.93, 0.24, and 2.91 A mg, respectively). Additionally, PtLa/C exhibited outstanding catalytic performance for MOR||HER, with a current density of 20 mA cm at 1.030 V, demonstrating good stability with negligible voltage changes after a 15 h chronoamperometry (CA) testing. This study provides a new strategy for synthesizing Pt-based catalysts with enhanced efficiency and low-energy input for HER||MOR.
开发清洁能源解决方案，如燃料电池和氢能，对于解决全球能源短缺至关重要。基于铂（Pt）的催化剂广泛应用于燃料电池和氢能生产（例如，通过水电解）。然而，在保持此类催化剂催化性能的同时减少Pt的用量至关重要。在此，采用简单的化学还原方法合成了具有不同Pt/La原子比的掺杂稀土元素镧（La）的PtLa催化剂（PtLa/C），得到了PtLa/C、PtLa/C、PtLa/C和Pt/C。这些PtLa/C催化剂在碱性条件下的甲醇氧化反应（MOR）、析氢反应（HER）及其耦合反应MOR||HER中表现出优异的电催化活性和稳定性。使用X射线衍射（XRD）、X射线光电子能谱（XPS）、透射电子显微镜（TEM）、像差校正扫描透射电子显微镜（AC-STEM）、原位傅里叶变换红外（FTIR）和操作拉曼光谱研究了La掺杂增强Pt基催化剂电催化性能和稳定性的机理。对于HER，La掺杂促进了HO在Pt位点的吸附和活化，改善了水的解离和OH脱附，并减少了OH对Pt的中毒。这提高了PtLa/C对HER的催化性能和稳定性。与商业20 wt% Pt/C（Pt/C-约翰逊·马西（JM））相比，PtLa/C在100 mA cm时的过电位仅为111 mV，而Pt/C-JM需要153 mV。对于MOR，La促进了CO键的断裂并减少了CO在Pt位点的吸附，从而提高了催化剂的性能和稳定性。PtLa/C对MOR的质量活性（MA）为4.44 A mg，比Pt/C-JM（0.36 A/mg）高12.33倍，超过了PtLa/C、PtLa/C和Pt/C（分别为2.93、0.24和2.91 A mg）。此外，PtLa/C在MOR||HER中表现出出色的催化性能，在1.030 V时电流密度为20 mA cm，在15小时计时电流法（CA）测试后电压变化可忽略不计，显示出良好的稳定性。本研究为合成用于HER||MOR的具有更高效率和低能量输入的Pt基催化剂提供了一种新策略。
