El-Gharbawy Sahar A, Al-Dossari Mawaheb, Zayed Mohamed, Saudi Heba A, Hassaan Mohamed Y, Alfryyan Nada, Shaban Mohamed
Department of Physics, Faculty of Science, Al-Azhar University (Girls' Branch), Nasr City, Cairo 11884, Egypt.
Housing and Building National Research Center, 87 El-Tahrir St., Dokki, Giza 1770, Egypt.
Nanomaterials (Basel). 2022 Jun 24;12(13):2169. doi: 10.3390/nano12132169.
Rock wool (RW) nanostructures of various sizes and morphologies were prepared using a combination of ball-mill and hydrothermal techniques, followed by an annealing process. Different tools were used to explore the morphologies, structures, chemical compositions and optical characteristics of the samples. The effect of initial particle size on the characteristics and photoelectrochemical performance of RW samples generated hydrothermally was investigated. As the starting particle size of ball-milled natural RW rises, the crystallite size of hydrothermally formed samples drops from 70.1 to 31.7 nm. Starting with larger ball-milled particle sizes, the nanoparticles consolidate and seamlessly combine to form a continuous surface with scattered spherical nanopores. Water splitting was used to generate photoelectrochemical hydrogen using the samples as photocatalysts. The number of hydrogen moles and conversion efficiencies were determined using amperometry and voltammetry experiments. When the monochromatic wavelength of light was increased from 307 to 460 nm for the manufactured RW>0.3 photocatalyst, the photocurrent density values decreased from 0.25 to 0.20 mA/mg. At 307 nm and +1 V, the value of the incoming photon-to-current efficiency was ~9.77%. Due to the stimulation of the H+ ion rate under the temperature impact, the Jph value increased by a factor of 5 when the temperature rose from 40 to 75 °C. As a result of this research, for the first time, a low-cost photoelectrochemical catalytic material is highlighted for effective hydrogen production from water splitting.
采用球磨和水热技术相结合的方法制备了各种尺寸和形貌的岩棉（RW）纳米结构，随后进行退火处理。使用不同的工具来探究样品的形貌、结构、化学成分和光学特性。研究了初始粒径对水热生成的RW样品的特性和光电化学性能的影响。随着球磨天然RW起始粒径的增加，水热形成样品的微晶尺寸从70.1 nm降至31.7 nm。从较大的球磨粒径开始，纳米颗粒固结并无缝结合形成具有分散球形纳米孔的连续表面。以样品作为光催化剂，利用水分解来产生光电化学氢。使用安培法和伏安法实验确定氢摩尔数和转换效率。对于制备的RW>0.3光催化剂，当光的单色波长从307 nm增加到460 nm时，光电流密度值从0.25 mA/mg降至0.20 mA/mg。在307 nm和+1 V时，入射光子到电流效率的值约为9.77%。由于温度影响下H+离子速率的刺激，当温度从40℃升至75℃时，Jph值增加了5倍。这项研究首次突出了一种低成本的光电化学催化材料，用于通过水分解有效制氢。
