Comparison of the photovoltaic efficiency on DSSC for nanometer sized TiO2 using a conventional sol–gel and solvothermal methods

Yeji Lee,Jinho Chae,강미숙 한국공업화학회 2010 Journal of Industrial and Engineering Chemistry Vol.16 No.4

When the two types of TiO2 coatings prepared by sol–gel and solvothermal methods were applied to dye-sensitized solar cell (DSSC) in this study, the energy conversion efficiency of the solvothermalmodified TiO2 was considerably higher than that on the sol–gel modified TiO2; approximately 8.51(solvothermal) and 5.93% (sol–gel) with the N719 dye under 100 mW/cm2 of simulated sunlight,respectively. These results are in agreement with an electrostatic forcemicroscopy (EFM) study showing that the electrons were transferred rapidly to the surface of the solvothermal-modified TiO2 film,compared with that on a sol–gel modified TiO2 film. Furthermore, FT-IR analysis of the films after N719dye adsorption showed that the solvothermal-modified TiO2 had a strong band at 500 cm1, which was assigned to metal–O, due to a new Ti–O bond between the O of COO and a Ti atom. This peak was considerably weaker in the sol–gel modified TiO2.

2P-48 Boehmite를 출발물질로 하는 solvothermal법에 의한 단분산 단결정형 α-Al2O3 입자 제조

조혜연,이승호,김대성,임형미,이영관 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.0

5.0 mol-% M (M=Fe, Co, Ni, Cu)-TiO2가 코팅된 현무암 섬유에서의 이산화탄소 광환원 반응

도정연,박선민,강미숙 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.0

화석연료의 사용량 증가로 인해 CO2 발생량이 증가하면서 전 세계적으로 CO2 저감 및 활용에 대한 연구가 활발히 진행되고 있다. 기후 변화와 지구온난화를 일으키는 CO2는 H2O와의 광환원 반응을 통해 메탄과 같은 연료로 전환이 가능하다. 이와 같은 방법은 CO2 감소뿐만 아니라 연료로서 재사용이 가능하다는 점에서 가치 있는 연구로 주목받고 있다. 본 연구에서는 현무암 섬유에 5.0 mol-% Metal (Fe, Co, Ni, Cu)-TiO2를 코팅하여 CO2 광환원 반응의 특성을 확인하고자 하였다. 코팅하고자 하는 금속 산화물은 모두 Solvothermal로 합성하였고, 이를 현무암 섬유에 코팅시켜 가장 좋은 광환원 성능을 나타내는 메탈성분을 찾고자 하였다. TiO2와 5.0 mol-% M(M=Fe, Co, Ni, Cu)가 함유된 TiO2가 코팅된 현무암 섬유 촉매의 특성은 XRD, UV-vis, PL, CO2-TPD 등을 통해 확인하였고, CO2 광환원 반응 결과 생성된 기체는 기체 크로마토그래피 TCD와 FID를 통해 분석하였다. 그 결과, 현무암 섬유에 TiO2를 코팅했을 때보다 전이금속들이 함유된 TiO2가 코팅되었을 때 CO2 광환원 성능이 더 좋은 것을 확인할 수 있었다.

Utilization of a ZnS(en)_0.5 photocatalyst hybridized with a CdS component for solar energy conversion to hydrogen

Kang, H.,Kim, J.H. VSP 2017 Advanced powder technology Vol.28 No.9

Photocatalytic solar energy conversion to chemical energy attracts great attention due to its high potential in harvesting renewable energy for the future. A ZnS(en)<SUB>0.5</SUB> photocatalyst hybridized with a CdS component was synthesized by solvothermal and precipitation methods to compare the effect of preparation methods on photocatalytic performance. The highest hydrogen production rate (559μmolg<SUP>-1</SUP>h<SUP>-1</SUP>) was achieved from a solvothermally synthesized ZnS(en)<SUB>0.5</SUB>-CdS composite at 80wt% of CdS content under standard 1-sun-irradiation condition (1000W/m<SUP>2</SUP>). Photocatalytic hydrogen production rates from ZnS(en)<SUB>0.5</SUB>-CdS photocatalysts were highly associated with degrees of charge separation, crystallinity, reduction power, and light absorption. By comparing two different routes for the synthesis of ZnS(en)<SUB>0.5</SUB>-CdS photocatalysts, solvothermally-fabricated material was shown to have a higher photocatalytic activity compared with material fabricated by a precipitation method. This improvement may be due to its excellent crystalline and charge-separation characteristics.

Formation of CuS with flower-like, hollow spherical, and tubular structures using the solvothermal-microwave process

Titipun Thongtem,Anukorn Phuruangrat,Somchai Thongtem 한국물리학회 2009 Current Applied Physics Vol.9 No.1

CuCl2 ․ 2H2O and CH3CSNH2 were dissolved in ethylene glycol, and followed by the addition of NaOH to form solutions with different pH values. Reactions proceeded in surfactant-free solutions contained in an acid digestion bomb using a microwave irradiation at different conditions. Pure CuS (hcp) with flower-like, hollow spherical, and tubular structures were detected, and had the same vibration wavenumber at 474 cm-1. They displayed two emission peaks at 411, and 432 nm. The formation of CuS with different morphologies was proposed according to the analytical results. CuCl2 ․ 2H2O and CH3CSNH2 were dissolved in ethylene glycol, and followed by the addition of NaOH to form solutions with different pH values. Reactions proceeded in surfactant-free solutions contained in an acid digestion bomb using a microwave irradiation at different conditions. Pure CuS (hcp) with flower-like, hollow spherical, and tubular structures were detected, and had the same vibration wavenumber at 474 cm-1. They displayed two emission peaks at 411, and 432 nm. The formation of CuS with different morphologies was proposed according to the analytical results.

나노; 1P-78 Sol-gel법과 Solvothermal법을 이용한 TiO2제조 및 염료감응 태양전지에서의 특성분석

강동천,이석호,임철현 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.0

Synthesis of metal-organic frameworks: A mini review

안화승,Yu-Ri Lee,Jun Kim 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.9

Metal organic frameworks (MOFs) are porous crystalline materials of one-, two-, or three-dimensional networks constructed from metal ions/clusters and multidentate organic linkers via coordination bonding, which are emerging as an important group of materials for energy storage, CO2 adsorption, alkane/alkene separation, and catalysis. To introduce newcomers in chemical engineering discipline to the rapidly expanding MOF research works, this review presents a brief introduction to the currently available MOFs synthesis methods. Starting from the conventional solvothermal/hydrothermal synthesis, microwave-assisted, sonochemical, electrochemical, mechanochemical, ionothermal, drygel conversion, and microfluidic synthesis methods will be presented. Examples will be limited to those representative MOF structures that can be synthesized using common organic ligands of 1,4-benzenedicarboxylic acid (and its functionalized forms) and 1,3,5-benzenetricarboxylic acid, in conjunction with metal nodes of Zn2+, Cu2+, Cr3+, Al3+,Fe3+ and Zr4+. Synthesis of widely-investigated zeolitic imidazolate framework (ZIF) structure, ZIF-8 is also included.

알코올-물 혼합용액을 이용하는 Solvothermal 법에 의한 나노크기의 TiO₂ 제조

이상근,박성수,홍성수,박종명,이승호,김대성,이근대,Lee, Sang Geun,Park, Seong Soo,Hong, Seong Soo,Park, Jong Myung,Lee, Seung Ho,Kim, Dae Sung,Lee, Gun Dae 한국공업화학회 2011 공업화학 Vol.22 No.6

본 연구에서는 $TiCl_4$ 출발물질 및 알코올과 물의 혼합용액을 이용한 solvothermal 법을 통하여 나노 크기의 $TiO_2$를 제조하였다. 이 때 혼합용액 중의 알코올의 종류 및 그 조성이 생성되는 $TiO_2$ 입자들의 결정상 혹은 응집상태에 미치는 영향에 대해 조사하였다. 생성물들의 물성은 X-선 회절법과 투과 및 주사전자 현미경을 이용하여 분석하였다. 1-부탄올/물의 부피 비가 각각 다른 혼합용매(1-부탄올/물; 100/0, 75/25, 50/50, 25/75, 0/100)를 이용한 solvothermal 법에 있어서 얻어진 루틸상의 $TiO_2$ 입자들의 응집상태는 1-부탄올/물의 비에 따라 변하였으며, 1-부탄올/물의 75/25 부피 비에서 잘 분산된 $TiO_2$ 나노 입자가 얻어졌다. 알코올과 물의 비를 75/25로 고정시킨 혼합 용매를 이용한 solvothermal 법에 있어서 알코올의 종류에 따라 생성되는 $TiO_2$ 입자들의 결정상이 변함을 확인하였다. 즉 메탄올, 에탄올 및 이소프로필 알코올의 혼합용액을 사용한 경우에는 아나타제상의 입자가 얻어지며 1-부탄올 혼합용액을 사용하면 루틸상의 $TiO_2$ 입자가 생성되었다. 이상의 결과들로부터 출발물질로는 $TiCl_4$를 그리고 반응용매로 알코올과 물의 혼합용액을 이용하며 더 이상의 첨가제를 사용하지 않는 solvothermal 법에 있어서는, 단순히 혼합용액의 조성 또는 알코올의 종류를 변화시킴으로써 생성되는 $TiO_2$ 입자들의 분산성 향상 및 결정상 조절이 가능한 것을 확인할 수 있었다. In this study, a solvothermal reaction to prepare nanocrystalline titania was carried out using $TiCl_4$ and mixed solvents of alcohol and water. The effects of the type and the composition of alcohol on the crystal structure and agglomeration of final $TiO_2$ products were investigated. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) as well as scanning electron microscopy (SEM). In the solvothermal reaction using the n-butanol solutions with different volume ratios of n-butanol/water (100/0, 75/25, 50/50, 25/75, 0/100), the extent of agglomeration of obtained rutile $TiO_2$ was found to change with the volume ratio of n-butanol/water, and the n-butanol/water ratio of 75/25 revealed the best result for the preparation of well-dispersed nanocrystalline $TiO_2$ powders. The crystal phase of $TiO_2$ prepared through the solvothermal reaction changed with the type of alcohol in solvent (alcohol/water = 75/25). $TiO_2$ products obtained with the aqueous solutions of methanol, ethanol and isopropanol have an anatase phase, while that with n-butanol has a rutile phase. The results showed that, in the solvothermal reaction using both $TiCl_4$ as a starting material and the alcohol-water mixed solvents without any other additive, the enhancement of dispersion and control of crystal structure of $TiO_2$ products can be feasible by simply varying the composition and type of alcohol in the mixed solvents.

알코올-물 혼합용액을 이용하는 Solvothermal 법에 의한 나노크기의 TiO2 제조

이상근 ( Sang Geun Lee ),박성수 ( Seong Soo Park ),홍성수 ( Seong Soo Hong ),박종명 ( Jong Myung Park ),이승호 ( Seung Ho Lee ),김대성 ( Dae Sung Kim ),이근대 ( Gun Dae Lee ) 한국공업화학회 2011 공업화학 Vol.22 No.6

본 연구에서는 TiCl4 출발물질 및 알코올과 물의 혼합용액을 이용한 solvothermal 법을 통하여 나노 크기의 TiO2를 제조하였다. 이 때 혼합용액 중의 알코올의 종류 및 그 조성이 생성되는 TiO2 입자들의 결정상 혹은 응집상태에 미치는 영향에 대해 조사하였다. 생성물들의 물성은 X-선 회절법과 투과 및 주사전자 현미경을 이용하여 분석하였다. 1-부탄올/물의 부피 비가 각각 다른 혼합용매(1-부탄올/물; 100/0, 75/25, 50/50, 25/75, 0/100)를 이용한 solvothermal 법에 있어서 얻어진 루틸상의 TiO2 입자들의 응집상태는 1-부탄올/물의 비에 따라 변하였으며, 1-부탄올/물의 75/25 부피 비에서 잘 분산된 TiO2 나노 입자가 얻어졌다. 알코올과 물의 비를 75/25로 고정시킨 혼합 용매를 이용한 solvothermal 법에 있어서 알코올의 종류에 따라 생성되는 TiO2 입자들의 결정상이 변함을 확인하였다. 즉 메탄올, 에탄올 및 이소프로필 알코올의 혼합용액을 사용한 경우에는 아나타제상의 입자가 얻어지며 1-부탄올 혼합용액을 사용하면 루틸상의 TiO2 입자가 생성되었다. 이상의 결과들로부터 출발물질로는 TiCl4를 그리고 반응용매로 알코올과 물의 혼합용액을 이용하며 더 이상의 첨가제를 사용하지 않는 solvothermal 법에 있어서는, 단순히 혼합용액의 조성 또는 알코올의 종류를 변화시킴으로써 생성되는 TiO2 입자들의 분산성 향상 및 결정상 조절이 가능한 것을 확인할 수 있었다. In this study, a solvothermal reaction to prepare nanocrystalline titania was carried out using TiCl4 and mixed solvents of alcohol and water. The effects of the type and the composition of alcohol on the crystal structure and agglomeration of final TiO2 products were investigated. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) as well as scanning electron microscopy (SEM). In the solvothermal reaction using the n-butanol solutions with different volume ratios of n-butanol/water (100/0, 75/25, 50/50, 25/75, 0/100), the extent of agglomeration of obtained rutile TiO2 was found to change with the volume ratio of n-butanol/water, and the n-butanol/water ratio of 75/25 revealed the best result for the preparation of well-dispersed nanocrystalline TiO2 powders. The crystal phase of TiO2 prepared through the solvothermal reaction changed with the type of alcohol in solvent (alcohol/water = 75/25). TiO2 products obtained with the aqueous solutions of methanol, ethanol and isopropanol have an anatase phase, while that with n-butanol has a rutile phase. The results showed that, in the solvothermal reaction using both TiCl4 as a starting material and the alcohol-water mixed solvents without any other additive, the enhancement of dispersion and control of crystal structure of TiO2 products can be feasible by simply varying the composition and type of alcohol in the mixed solvents.

용매열합성법에 의한 나노기공 HKUST-1 막의 제조 및 기체투과 특성

노승준,김진수 한국막학회 2012 멤브레인 Vol.22 No.6

본 연구에서는 용매열합성법(solvothermal method)을 이용해 나노기공 HKUST-1 분리막을 제조하였다. In-situ 용매열합성법을 이용하는 경우, 매크로 기공의 알루미나 지지체 위에 균일하고 균열이 없는 HKUST-1 층을 형성하기 어렵다. 본 연구에서는 용매열합성 전에 알루미나 지지체의 표면을 가열한 상태에서 용매열합성의 전구체 용액을 분무하므로 연속적이고 균열이 없는 HKUST-1 분리막을 제조할 수 있었다. 합성된 HKUST-1 분리막은 XRD, FE-SEM 및 단일 기체투과 실험 등을 통해 분석하였다. In this study, nanoporous HKUST-1 membranes were synthesized by solvothermal method. It is very difficult to prepare uniform and crack-free HKUST-1 layer on macroporous alumina support by in-situ solvothermal method. In this study, continuous and crack-free HKUST-1 membranes could be obtained by spraying solvothermal precursor solution on the heated alumina support, followed by solvothermal synthesis. HKUST-1 membranes were characterized by XRD, FE-SEM and single gas permeation experiments.