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Abstrak :
Zinc oxide (ZnO) nanorods have been considered as a potential semiconductor oxide material for the application of dye-sensitized solar cells (DSSC). Various experiments have been conducted to improve its nanostructural characteristics and functional properties in order to make it well suited for enhancing DSSC’ performance. Inspired by such studies, the ZnO nanorods array was grown on indium tin oxide (InSn2O3, ITO) substrate in the present work. For this purpose, a seed solution was prepared at low temperature (0oC) using zinc nitrate tetrahydrate and hexamethylenetetramine. The ZnO seed layers were deposited onto ITO glass using a spin-coating technique and further annealed at two different temperatures, 200 and 400 oC. The seeding was also varied between one, three and five layers, prior to the growing process using the chemical bath deposition method (CBD). The results showed that the annealing temperatures significantly influenced the ZnO nanorods’ growth. The optimal condition was achieved by using three seed layers annealed at 200oC, providing an average diameter of 157.58 nm, the biggest crystallite size (up to 59.63 nm), and a band-gap energy (Eg) of 3.27 eV. Based on the obtained properties, the growth of ZnO nanorods on ITO substrate in this work has the potential to be used for the application of dye-sensitized solar cells.

Abstrak :
Zinc Oxide ZnO merupakah salah satu bahan semikonduktor yang banyak diteliti sebagai fotokatalis, namun salah satu kelemahan ZnO adalah rekombinasi yang cepat antara elektron dengan hole yang mengakibatkan efisiensi aktifitas fotokatalitik rendah. Salah satu upaya untuk menekan rekombinasi ini adalah dengan membuat struktur komposit ZnO dengan nanopartikel logam mulia Au dan Ag yang dapat menangkap elektron. Pada penelitian ini dilakukan sintesis nanopartikel AuAg pada nanorod ZnO yang ditumbuhkan di atas kaca dengan metode one-pot hydrothermal. Rasio mol prekursor Au:Ag 1:0 ; 3:1 ; 1:1 ; 1:3 dan 0:1. Hasil FESEM dan TEM menunjukkan bahwa umumnya nanopartikel Au terbentuk dengan diameter 15-30 nm cukup banyak di permukaan nanorod ZnO. Dengan penambahan unsur Ag terlihat jumlah nanopartikel yang terbentuk lebih sedikit dan ukurannya menjadi lebih beragam bahkan terjadi aglomerasi. Nanopartikel AuAg yang terbentuk memiliki struktur kristal fcc dengan bidang dominan 111. ......Zinc Oxide ZnO is one of the most studied semiconductor materials as a photocatalyst, but one of the weaknesses of ZnO is rapid recombination between electrons and holes resulting in low photocatalytic activity efficiency. One attempt to suppress this recombination is to create a ZnO composite structure with noble metal nanoparticles Au and Ag that can capture electrons. In this study, the synthesis of AuAg nanoparticles on ZnO nanorods was grown on glass by one pot hydrothermal method. The mole ratio of Au precursors Ag 1 0 3 1 1 1 1 3 and 0 1. FESEM and TEM results show that generally Au nanoparticles are formed with a diameter of 15 30 nm in large number on the surface of ZnO nanorods. With the addition of Ag elements it is seen that the number of nanoparticles formed is less and the size becomes more diverse and even the agglomeration occurs. The AuAg nanoparticles formed have an face center cubic crystal structure with a dominant 111 crystal plane.

Abstrak :
The AlInGaN and ZnO materials systems have proven to be one of the scientifically and technologically important areas of development over the past 15 years, with applications in UV/visible optoelectronics and in high-power/high-frequency microwave devices. The pace of advances in these areas has been remarkable and the wide band gap community relies on books like the one we are proposing to provide a review and summary of recent progress.