Chhetri Manjeet, Gupta Uttam, Yadgarov Lena, Rosentsveig Rita, Tenne Reshef, Rao C N R
New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P. O., Bangalore 560064, India.
Dalton Trans. 2015 Oct 7;44(37):16399-404. doi: 10.1039/c5dt02562a.
Electrochemical generation of hydrogen by non-precious metal electrocatalysts at a lower overpotential is a focus area of research directed towards sustainable energy. The exorbitant costs associated with Pt-based catalysts is the major bottleneck associated with commercial-scale hydrogen generation. Strategies for the synthesis of cost-effective and stable catalysts are thus key for a prospective 'hydrogen economy'. In this report, we highlight a novel and general strategy to enhance the electrochemical activity of molybdenum disulfide (MoS2) in a fullerene structure (IF-). In particular, pristine (undoped) and rhenium-doped nanoparticles of MoS2 with fullerene-like structures (IF-MoS2) were studied, and their performance as catalysts for the hydrogen evolution reaction (HER) was compared to that of 2H-MoS2 particles (platelets). The current density of the IF-MoS2 was higher by one order of magnitude than that of few-layer (FL-) MoS2, due to the enhanced density of the edge sites. Furthermore, Re doping of as low as 100 ppm in IF-MoS2 decreased the onset potential by 60-80 mV and increased the activity by 60 times compared with that of the FL-MoS2. The combined synergistic effect of Re doping and the IF structure not only changes the intrinsic nature of the MoS2 but also increases its reactivity. This strategy highlights the potential use of the IF structure and Re doping in electrocatalytic hydrogen evolution using MoS2-based catalysts.
通过非贵金属电催化剂在较低过电位下电化学产氢是可持续能源研究的一个重点领域。与铂基催化剂相关的高昂成本是商业规模制氢的主要瓶颈。因此，合成具有成本效益且稳定的催化剂的策略是未来“氢经济”的关键。在本报告中，我们重点介绍了一种新颖且通用的策略，以增强富勒烯结构（IF-）中硫化钼（MoS2）的电化学活性。具体而言，研究了具有类富勒烯结构的原始（未掺杂）和铼掺杂的MoS2纳米颗粒（IF-MoS2），并将它们作为析氢反应（HER）催化剂的性能与2H-MoS2颗粒（薄片）进行了比较。由于边缘位点密度的增加，IF-MoS2的电流密度比少层（FL-）MoS2高一个数量级。此外，IF-MoS2中低至100 ppm的铼掺杂使起始电位降低了60 - 80 mV，与FL-MoS2相比活性提高了60倍。铼掺杂和IF结构的联合协同效应不仅改变了MoS2的固有性质，还提高了其反应活性。该策略突出了IF结构和铼掺杂在基于MoS2的催化剂电催化析氢中的潜在应用。
