Synthesis of ZSM‐5 Films and Monoliths with Bimodal Micro/Mesoscopic Structures
Seung Il Cho, Sun-Woo Choi, J.‐H. Kim, G.‐J. Kim
IF 19
Advanced Functional Materials
Abstract A route to synthesize ZSM‐5 crystals with a bimodal micro/mesoscopic pore system has been developed in this study; the successful incorporation of the mesopores within the ZSM‐5 structure was performed using tetrapropylammonium hydroxide (TPAOH)‐impregnated mesoporous materials containing carbon nanotubes in the pores, which were encapsulated in the ZSM‐5 crystals during a solid rearrangement process within the framework. Such mesoporous ZSM‐5 zeolites can be readily obtained as powders, thin films, or monoliths.
In Situ Radiation Hardness Study of Amorphous Zn–In–Sn–O Thin-Film Transistors with Structural Plasticity and Defect Tolerance
Dongil Ho, Sun-Woo Choi, Hyun‐Woo Kang, Byungkyu Park, Minh Nhut Le, Sung Kyu Park, Myung‐Gil Kim, Choongik Kim, Antonio Facchetti
IF 8.2
ACS Applied Materials & Interfaces
Solution-processed metal-oxide thin-film transistors (TFTs) with different metal compositions are investigated for ex situ and in situ radiation hardness experiments against ionizing radiation exposure. The synergetic combination of structural plasticity of Zn, defect tolerance of Sn, and high electron mobility of In identifies amorphous zinc-indium-tin oxide (Zn-In-Sn-O or ZITO) as an optimal radiation-resistant channel layer of TFTs. The ZITO with an elemental blending ratio of 4:1:1 for Zn/In/Sn exhibits superior ex situ radiation resistance compared to In-Ga-Zn-O, Ga-Sn-O, Ga-In-Sn-O, and Ga-Sn-Zn-O. Based on the in situ irradiation results, where a negative threshold voltage shifts and a mobility increase as well as both off current and leakage current increase are observed, three factors are proposed for the degradation mechanisms: (i) increase of channel conductivity, (ii) interface-trapped and dielectric-trapped charge buildup, and (iii) trap-assisted tunneling in the dielectric. Finally, in situ radiation-hard oxide-based TFTs are demonstrated by employing a radiation-resistant ZITO channel, a thin dielectric (50 nm SiO<sub>2</sub>), and a passivation layer (PCBM for ambient exposure), which exhibit excellent stability with an electron mobility of ∼10 cm<sup>2</sup>/V s and aΔ<i>V</i><sub>th</sub> of <3 V under real-time (15 kGy/h) gamma-ray irradiation in an ambient atmosphere.
Formation mechanism and characteristics of Au-Sn-O and Sn-O nanocompounds with various band gaps through flame chemical vapor deposition process
Myung Sik Choi, Han Gil Na, Sun-Woo Choi, Kyu Hyoung Lee, Changhyun Jin
IF 6.8
Alexandria Engineering Journal
After forming the double layer of SnO 2 and Au, the compound of Sn and O with multiple band gaps was formed in a short time period via flame chemical vapor deposition (FCVD). The Sn component of SnO 2 has fluidity and is the only one moving to the discrete Au side and leaving O behind. The capillarity of Sn allows it to form a unique structure with Au-Sn-O nanoparticles and amorphous Sn-O nanotubes of multiple compositions in a single process. For verification, the gradual morphological, crystallographic, compositional, and optical changes in the material were sequentially presented as per the degree of FCVD.
Synthesis of ZSM‐5 Films and Monoliths with Bimodal Micro/Mesoscopic Structures
Seung Il Cho, Sun-Woo Choi, J.‐H. Kim, G.‐J. Kim
IF 19
Advanced Functional Materials
Abstract A route to synthesize ZSM‐5 crystals with a bimodal micro/mesoscopic pore system has been developed in this study; the successful incorporation of the mesopores within the ZSM‐5 structure was performed using tetrapropylammonium hydroxide (TPAOH)‐impregnated mesoporous materials containing carbon nanotubes in the pores, which were encapsulated in the ZSM‐5 crystals during a solid rearrangement process within the framework. Such mesoporous ZSM‐5 zeolites can be readily obtained as powders, thin films, or monoliths.