Although nickel-based catalysts display good catalytic capability and excellent corrosion resistance under alkaline electrolytes for water splitting, it is still imperative to enhance their activity for real device applications. Herein, we decorated Ni_0.85Se hollow nanospheres onto reduced graphene oxide (RGO) through a hydrothermal route, then annealed this composite at different temperatures (400 °C, NiSe₂-400 and 450 °C, NiSe₂-450) under argon atmosphere, yielding a kind of NiSe₂/RGO composite catalysts. Positron annihilation spectra revealed two types of vacancies formed in this composite catalyst. We found that the NiSe₂-400 catalyst with dual Ni-Se vacancies is able to catalyze the oxygen evolution reaction (OER) efficiently, needing a mere 241 mV overpotential at 10 mA·cm⁻². In addition, this catalyst exhibits outstanding stability. Computational studies show favorable energy barrier on NiSe₂-400, enabling moderate OH⁻ adsorption and O₂ desorption, which leads to the enhanced energetics for OER.

尽管镍基催化剂在碱性电解质用于水分解时显示出良好的催化能力和出色的耐腐蚀性，但仍必须在实际设备应用中提高其活性。本文中，我们通过水热法将Ni _0.85 Se空心纳米球装饰在还原的氧化石墨烯（RGO）上，然后在氩气气氛下在不同温度（400°C，NiSe ₂ -400和450°C，NiSe ₂ -450）下对该复合材料进行退火，得到一种NiSe ₂ / RGO复合催化剂。正电子an没光谱揭示了在该复合催化剂中形成的两种空位。我们发现NiSe ₂具有双重Ni-Se空位的-400催化剂能够有效催化氧释放反应（OER），在10 mA·cm ^-2下仅需241 mV超电势。另外，该催化剂表现出优异的稳定性。计算研究表明上NISE有利的能量势垒₂ -400，使中等OH ^-吸附和O ₂解吸，这导致用于OER增强能量学。