Research Center for Analytical Sciences, College of Chemistry, Nankai University, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Tianjin, 300071, China.
State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, China.
Small. 2021 Dec;17(52):e2104195. doi: 10.1002/smll.202104195. Epub 2021 Nov 2.
The authors proposed a novel template-free strategy, urease-mediated interfacial growth of NH Ga(OH) CO nanotubes at 20-50 °C, to fabricate the porous Ga O nanotubes. The subtlety of the proposed strategy is all the products from urea enzymolysis are utilized in formation of NH Ga(OH) CO precipitates, and the key for interfacial growth of NH Ga(OH) CO nanotubes is the dynamic match between the rate of CO bubble fusion and NH Ga(OH) CO precipitation. The proposed strategy works well for the doped porous Ga O nanotubes. As a proof-of-concept, the porous β-Ga O and β-Ga O :Cr nanotubes are used as photocatalysts or co-catalysts with Pt, for H evolution from water splitting. The H evolution rate of porous β-Ga O nanotubes reach 39.3 mmol g h with solar-to-hydrogen (STH) conversion efficiency of 2.11% (Hg lamp) or 498 µmol g h with STH of 0.03% (Xe lamp) respectively, both about 3 times of β-Ga O nanoparticles synthesized at pH 9.0 without urease. The Cr-doping enhances the in-the-dark H evolution rate pre-lighted by Hg lamp, and Pt co-catalysis further elevates the H evolution rate, for instance, the H evolution rate of Pt-loaded β-Ga O :Cr nanotubes reaches 54.7 mmol g h with STH of 2.94% under continuous lighting of Hg lamp and 1062 µmol g h in-the-dark.
作者提出了一种新颖的无模板策略，即在 20-50°C 下通过脲酶介导的 NH4Ga(OH)CO3 纳米管的界面生长，来制备多孔 Ga2O3 纳米管。该策略的精妙之处在于脲酶水解的所有产物都被用于 NH4Ga(OH)CO3 沉淀物的形成，而 NH4Ga(OH)CO3 纳米管界面生长的关键是 CO2 气泡融合和 NH4Ga(OH)CO3 沉淀的速率之间的动态匹配。该策略很好地适用于掺杂多孔 Ga2O3 纳米管。作为概念验证，多孔β-Ga2O3 和β-Ga2O3:Cr 纳米管被用作光催化剂或与 Pt 的共催化剂，用于水分解析氢。多孔β-Ga2O3 纳米管的析氢速率分别达到 39.3 mmol g h-1（Hg 灯）或 498 µmol g h-1（Xe 灯），相应的太阳能到氢（STH）转换效率分别为 2.11%（Hg 灯）和 0.03%（Xe 灯），这分别是在没有脲酶时在 pH 9.0 下合成的β-Ga2O3 纳米粒子的 3 倍。Cr 掺杂增强了 Hg 灯预光照下的暗反应析氢速率，Pt 共催化进一步提高了析氢速率，例如，Pt 负载的β-Ga2O3:Cr 纳米管在 Hg 灯连续光照下的析氢速率达到 54.7 mmol g h-1，在暗反应中的析氢速率达到 1062 µmol g h-1。
