Bekmyrza Kenzhebatyr Zh, Kuterbekov Kairat A, Kabyshev Asset M, Kubenova Marzhan M, Baratova Aliya A, Aidarbekov Nursultan, Chaka Mesfin Diro, Benti Natei Ermias
Faculty of Engineering, Caspian University of Technology and Engineering named after Sh.Yessenov, Aktau, 130000, Kazakhstan.
Institute of Physical and Technical Sciences, L.N. Gumilyov Eurasian National University, Astana, 010008, Kazakhstan.
Sci Rep. 2025 Aug 4;15(1):28418. doi: 10.1038/s41598-025-08306-6.
Hydrogen energy generation faces challenges in efficiency and economic viability due to reliance on scarce noble metal catalysts. This study aimed to develop platinum-doped nickel-iron metal-organic framework (Pt-NiFe-MOF) catalysts with controlled metal ratios and pore architecture for enhanced water electrolysis. The NiFe-MOF framework was first synthesized via a solvothermal method, which was then subjected to post-synthetic modification to introduce controlled platinum loadings (0.5-2.0 wt%). The pore structure was tuned using a mixed-linker strategy (H₄DOBDC ratios 1:0 to 1:1). Catalysts were characterized using PXRD, HRTEM, BET, XPS, and ICP-OES techniques. Electrochemical performance was analyzed in 1.0 M KOH. A custom-designed integrated electrolysis system at 75 °C assessed practical performance. The Pt-NiFe-MOF-1.0 catalyst with H₄DOBDC ratio of 1:0.5 achieved remarkable effectiveness, requiring overpotentials of only 253 mV for OER and 58 mV for HER when operating at 10 mA/cm². This catalyst featured an optimal pore diameter of 4.2 nm and surface area of 1325 m²/g. DFT calculations revealed platinum incorporation created synergistic effects by modifying hydrogen binding energies. Furthermore, DFT calculations and XPS analysis revealed that the role of platinum in the OER is not direct catalysis, but rather a powerful electronic modulation effect; Pt dopants withdraw electron density from adjacent Ni and Fe centers, promoting the formation of higher-valent Ni³⁺/Fe³⁺ species that are intrinsically more active and lowering the energy barrier for the rate-determining O-O bond formation step. The integrated system achieved 1.62 V at 100 mA/cm² with 75.8% energy efficiency, maintaining stability for 200 h with 15-30 times lower precious metal loading than conventional systems. Strategic incorporation of low platinum concentrations within optimized NiFe-MOF structures significantly enhances water electrolysis performance while maintaining economic viability, advancing development of industrial-scale hydrogen generation systems.
由于依赖稀缺的贵金属催化剂，氢能生产在效率和经济可行性方面面临挑战。本研究旨在开发具有可控金属比例和孔结构的铂掺杂镍铁金属有机框架（Pt-NiFe-MOF）催化剂，以增强水电解性能。首先通过溶剂热法合成NiFe-MOF框架，然后进行后合成修饰以引入可控的铂负载量（0.5-2.0 wt%）。使用混合连接体策略（H₄DOBDC比例为1:0至1:1）调节孔结构。使用PXRD、HRTEM、BET、XPS和ICP-OES技术对催化剂进行表征。在1.0 M KOH中分析电化学性能。在75°C下使用定制设计的集成电解系统评估实际性能。H₄DOBDC比例为1:0.5的Pt-NiFe-MOF-1.0催化剂表现出显著的效果，在10 mA/cm²下运行时，析氧反应（OER）的过电位仅为253 mV，析氢反应（HER）的过电位为58 mV。该催化剂的最佳孔径为4.2 nm，表面积为1325 m²/g。密度泛函理论（DFT）计算表明，铂的掺入通过改变氢结合能产生协同效应。此外，DFT计算和XPS分析表明，铂在OER中的作用不是直接催化，而是强大的电子调制效应；铂掺杂剂从相邻的镍和铁中心提取电子密度，促进更高价态的Ni³⁺/Fe³⁺物种的形成，这些物种本质上更具活性，并降低了速率决定步骤O-O键形成的能垒。该集成系统在100 mA/cm²下实现了1.62 V的电压，能量效率为75.8%，在贵金属负载量比传统系统低15-30倍的情况下保持了200小时的稳定性。在优化的NiFe-MOF结构中战略性地掺入低浓度铂，可显著提高水电解性能，同时保持经济可行性，推动工业规模制氢系统的发展。
