Robust route to H2O2 and H2 via intermediate water splitting enabled by capitalizing on minimum vanadium-doped piezocatalysts

作者：Li, Yuekun; Li, Li; Liu, Fangyan; Wang, Biao; Gao, Feng; Liu, Chuan; Fang, Jingyun; Huang, Feng; Lin, Zhang; Wang, Mengye^*

来源：Nano Research, 2022, 15(9): 7986-7993.

DOI：10.1007/s12274-022-4506-0

• water splitting
• H-2 evolution
• H(2)O(2 )production
• piezocatalysis
• vanadium-doped NaNbO3

H2O2 is an environmentally friendly chemical for a wide range of water treatments. The industrial production of H2O2 is an anthraquinone oxidation process, which, however, consumes extensive energy and produces pollution. Here we report a green and sustainable piezocatalytic intermediate water splitting process to simultaneously obtain H2O2 and H-2 using single crystal vanadium (V)-doped NaNbO3 (V-NaNbO3) nanocubes as catalysts. The introduction of V improves the specific surface area and active sites of NaNbO3. Notably, V-NaNbO3 piezocatalysts of 10 mg exhibit 3.1-fold higher piezocatalytic efficiency than the same catalysts of 50 mg, as more piezocatalysts lead to higher probability of aggregation. The aggregation causes reducing active sites and decreased built-in electric field due to the neutralization between different nano-catalysts. Remarkably, piezocatalytic H2O2 and H-2 production rates of V-NaNbO3 (10 mol%) nanocubes (102.6 and 346.2 mu mol.g(-1).h(-1), respectively) are increased by 2.2 and 4.6 times compared to the as-prepared pristine NaNbO3 counterparts, respectively. This improved catalytic efficiency is attributed to the promoted piezo-response and more active sites of NaNbO3 catalysts after V doping, as uncovered by piezoresponse force microscopy (PFM) and density functional theory (DFT) simulation. More importantly, our DFT results illustrate that inducing V could reduce the dynamic barrier of water dissociation over NaNbO3, thus enhancing the yield of H2O2 and H-2. This facile yet robust piezocatalytic route using minimal amounts of catalysts to obtain H2O2 and H-2 may stand out as a promising candidate for environmental applications and water splitting.

• 单位
  中山大学