In Situ Magnetic Alignment of a Slurry of Tandem Semiconductor Microwires Using a Ni Catalyst
In Situ Magnetic Alignment of a Slurry of Tandem Semiconductor Microwires Using a Ni Catalyst
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使用镍催化剂对串联半导体微线浆料进行原位磁对准
DOI：
10.1002/smll.202103822
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发表时间：
2021
期刊：
影响因子：
13.3
通讯作者：
Spurgeon, Joshua M.
中科院分区：
文献类型：
--
作者：
Gulati, Saumya;Mulvehill, Matthew C.;Pishgar, Sahar;Spurgeon, Joshua M.
能够单独进行无辅助光驱动水分解的半导体颗粒浆料被建模为具有低成本太阳能制氢的有希望的途径，但它们的效率很低。串联微粒系统是追求提高效率的明确方向。然而，光吸收必须在串联中小心管理，以防止子电池中的电流失配，这对悬浮在液体中的串联微丝颗粒提出了可能的挑战。在这项工作中，Ni催化的Si/TiO 2串联微丝浆料被用作理想带隙组合的替代品，以证明无辅助水分解微丝与外部磁场的原位对准的概念验证。Ni析氢催化剂选择性地光沉积在暴露的Si微丝芯上，以用作阴极位点以及用于磁取向的手柄。悬浮的微丝的取向角的频率分布被确定为分散和没有上升的微泡下的磁场强度的函数。磁化后的镍灯泡，串联微丝可以在磁场下的水中高度对齐，尽管从起泡或对流的积极分散。
Slurries of semiconductor particles individually capable of unassisted light‐driven water‐splitting are modeled to have a promising path to low‐cost solar hydrogen generation, but they have had poor efficiencies. Tandem microparticle systems are a clear direction to pursue to increase efficiency. However, light absorption must be carefully managed in a tandem to prevent current mismatch in the subcells, which presents a possible challenge for tandem microwire particles suspended in a liquid. In this work, a Ni‐catalyzed Si/TiO2tandem microwire slurry is used as a stand‐in for an ideal bandgap combination to demonstrate proof‐of‐concept in situ alignment of unassisted water‐splitting microwires with an external magnetic field. The Ni hydrogen evolution catalyst is selectively photodeposited at the exposed Si microwire core to serve as the cathode site as well as a handle for magnetic orientation. The frequency distribution of the suspended microwire orientation angles is determined as a function of magnetic field strength under dispersion with and without uplifting microbubbles. After magnetizing the Ni bulb, tandem microwires can be highly aligned in water under a magnetic field despite active dispersion from bubbling or convection.