Abstract:
High-performance production of green hydrogen gas is necessary to develop renewable energy generation technology and to safeguard the living environment. This study reports a controllable engineering approach to tailor the structure of nickel-layered double hydroxides via doped and absorbed platinum single atoms (PtSA) promoted by low electronegative transition metal (Mn, Fe) moieties (PtSA-Mn,Fe-Ni LDHs). We explore that the electron donation from neighboring transition metal moieties results in the well-adjusted d-band center with the low valence states of PtSA(doped) and PtSA(ads.), thus optimizing adsorption energy to effectively accelerate the H2 release. Meanwhile, a tailored local chemical environment on transition metal centers with unique charge redistribution and high valence states functions as the main center for H2O catalytic dissociation into oxygen. Therefore, the PtSA-Mn,Fe-Ni LDH material possesses a small overpotential of 42 and 288 mV to reach 10 mA·cm-2 for hydrogen and oxygen evolution, respectively, superior to most reported LDH-based catalysts. Additionally, the mass activity of PtSA-Mn,Fe-Ni LDHs proves to be 15.45 times higher than that of commercial Pt-C. The anion exchange membrane electrolyzer stack of PtSA-Mn,Fe-Ni LDHs(+,-) delivers a cell voltage of 1.79 V at 0.5 A·cm-2 and excellent durability over 600 h. This study presents a promising electrocatalyst for a practical water splitting process.
摘要:
绿色氢气的高效生产是发展可再生能源发电技术和维护生活环境的必要条件。这项研究报告了一种可控的工程方法,可通过低电负性过渡金属(Mn,Fe)部分(PtSA-Mn,Fe-NiLDHs)。我们探索了来自相邻过渡金属部分的电子捐赠导致具有PtSA(掺杂)和PtSA(ads)的低价态的良好调整的d带中心。),从而优化吸附能量以有效加速H2释放。同时,在具有独特电荷再分布和高价态的过渡金属中心上定制的局部化学环境作为H2O催化解离为氧的主要中心。因此,PtSA-Mn,Fe-NiLDH材料具有42和288mV的小超电势,可达到10mA·cm-2的氢和氧析出,分别,优于大多数报道的LDH基催化剂。此外,PtSA-Mn的质量活性,Fe-NiLDHs被证明是商业Pt-C的15.45倍。PtSA-Mn的阴离子交换膜电解槽堆,Fe-NiLDHs(+,-)在0.5A·cm-2时提供1.79V的电池电压,并在600h内具有出色的耐用性。这项研究为实际的水分解过程提供了一种有前途的电催化剂。