Highly dispersed Ni2P clusters inlaid in micropore openings on mesoporous ZSM-5 zeolite and its catalytic performance in the phenylacetylene semi-hydrogenation

Wenqian Fu,Lei Zhang,TingYu Tao,Tiandi Tang 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.95 No.-

Preparation of Ni2P phase with cluster size and high stability is significant for enhancing its catalyticperformance. Herein, Ni2P nanoclusters (<1 nm) inlaid in micropore openings on mesoporous ZSM-5zeolite (MZSM-5) was prepared through citric acid-assisted, two-step impregnation method under thereduction temperature of 400 C. The facilitation effect of the citric acid and support surface properties onthe formation of Ni2P clusters was investigated. The formation of Ni(H2cit)+ complex promotes thedispersion of the Ni precursor on the zeolite surface. After calcination, the free Ni species interactstronger with the acidic hydroxyl groups on MZSM-5 than that with silanol on mesoporous TS-1(MTS-1),Silicalite-1 (MSilicalite-1) and SiO2, facilitating the formation of Ni2P nanoclusters on the MZSM-5micropore openings after the calcined Ni catalyst was loaded with P species and followed by activationtreatment. The obtained Ni2P clusters exhibit higher intrinsic activity (robs = 1.50 mol kg 1 s 1) than MTS-1, MSilicalite-1 and SiO2 supported Ni2P catalysts (0.80, 0.76, 0.40 mol kg 1 s 1) in the semihydrogenationof phenylacetylene.

WCI6-EtAICI2 촉매에 의한 폴리(페닐아세틸렌)의 합성과 전자-광 및 전기화학적 특성연구

제갈영순 ( Yeong Soon Jae Gal ),진성호 ( Sung Ho Jin ),장상희 ( Sang Hee Jang ),임권택 ( Kwon Taek Lim ) 한국화상학회 2011 한국화상학회지 Vol.17 No.3

Poly(phenylacetylene) with relatively high molecular weight was prepared by using WCl6-EtAlCl2catalystsystem.This polymerization proceeded well in the mild reaction condition to give a high yield of polymer (polymer yield: 81 %). The chemical structure of poly(phenylacetylene) was characterized by such instrumental methods as NMR (1H-,13C-),IR,UV-visiblespectroscopies,andelementalanalysistohavetheconjugatedpolymerbackbonebearingphenylsubstituents. The photoluminescence maximum peak of polymer was located at 424 nm, which corresponds to the photon energy of 2.93 eV. The cyclovoltammograms of poly(phenylacetylene) exhibited the electrochemically stable window at the -1.5 ~ +1.5 V region. The kinetics of the redox process of poly(phenylacetylene) was found to be mainly controlled by the reactant diffusion process based on the experiment of the oxidation current density of polymer versus the scan rate.

WCl_6-EtAlCl_2 촉매에 의한 폴리(페닐아세틸렌)의 합성과 전자-광 및 전기화학적 특성연구

제갈영순,진성호,장상희,임권택 한국화상학회 2011 한국화상학회지 Vol.17 No.3

WCl_6-EtAlCl_2촉매계를 이용하여 비교적 큰 분자량을 갖는 폴리(페닐아세틸렌)을 합성하였다. 중합반응이 잘 진행되었으며 중합수율은 81%였다. 합성한 폴리(페닐아세틸렌) 분자구조를 NMR (^1H-,^13C-),IR,UV-visible,원소분석 등으로 분석한 결과 페닐 치환기를 갖는 공액구조 고분자가 합성되었음을 확인할 수 있었다. 아울러 332 nm의 빛으로 여기시킬 경우 PL 최대 peak는 424 nm에서 관찰되었는데, 이는 2.93 eV의 광 에너지에 해당한다. 이 고분자의 순환 전압전류 그림은 도핑과 탈도핑사이에서 비가역적인 전기화학적 거동을 보여주었다. 이 고분자의 전기화학적 과정이 매우 안정하였으며, 스캔속도에 따른 산화전류밀도 실험으로부터 이 고분자의 산화-환원 과정은 확산-제어과정에 따르는 것으로 분석되었다. Poly(phenylacetylene) with relatively high molecular weight was prepared by using WCl_6-EtAlCl_2catalystsystem.This polymerization proceeded well in the mild reaction condition to give a high yield of polymer (polymer yield: 81 %). The chemical structure of poly(phenylacetylene) was characterized by such instrumental methods as NMR (^1H-,^13C-),IR,UV-visiblespectroscopies,andelementalanalysistohavetheconjugatedpolymerbackbonebearingphenylsubstituents. The photoluminescence maximum peak of polymer was located at 424 nm, which corresponds to the photon energy of 2.93 eV. The cyclovoltammograms of poly(phenylacetylene) exhibited the electrochemically stable window at the -1.5 ~ +1.5 V region. The kinetics of the redox process of poly(phenylacetylene) was found to be mainly controlled by the reactant diffusion process based on the experiment of the oxidation current density of polymer versus the scan rate.

Electro-Optical and Electrochemical Properties of Poly(phenylacetylene)

Gal, Yeong-Soon,Lee, Won-Chul,Jin, Sung-Ho,Park, Young-Il,Park, Jong-Wook,Lim, Kwon Taek,Kim, Sang Youl TaylorFrancis 2009 Molecular Crystals and Liquid Crystals Vol.513 No.1

<P> Poly(phenylacetylene)[Poly(PA)] was prepared by the polymerization of phenylacetylene with the catalyst of (NBD)PdCl2. The instrumental analysis data on the polymer structure revealed that the poly(PA) have the conjugated polyene backbone structure with phenyl substituents. The band gap energy of poly(PA) was estimated to be 2.51 eV and the photoluminescence spectra of poly(PA) showed that the photoluminescence peak is located at 439 nm, corresponding to a photon energy of 2.82 eV. The cyclovoltamograms of poly(PA) exhibited that the irreversible oxidation and reduction were occurred at 0.38 V and -0.93 V, respectively (vs Ag/AgNO3). The redox current value gradually increased as the scan rate increased.</P>

Electro-optical and electrochemical properties of poly(phenylacetylene) prepared by palladium-based catalysts

류재민,제갈영순,진성호,박영일,박종욱 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.0

The examined applications of conjugated polymers include organic light-emitting diodes (OLEDs), chemical sensors, photovoltaic cells, field-effect transistors, and so on. The acetylenic triple bonds have rich π-electrons, which can be easily polymerized to yield the linear conjugated polymer systems. Here, we prepared poly(phenylacetylene)s by using the palladium-based catalysts. The instrumental analysis data on the polymer structure revealed that the polymer have the conjugated polyene backbone structure with phenyl substituents. The band gap energy of polymer was estimated to be 2.51 eV and the photoluminescence spectra of polymer showed that the photoluminescence peak is located at 439 nm, corresponding to a photon energy of 2.82 eV. The cyclovoltamograms of polymer exhibited that the irreversible oxidation and reduction were occurred at 0.38V and 0.93 V, respectively.

Solvent effect on the excited state of stilbene dendrimers bearing phenylacetylene groups

Nishimura, Yoshinobu,Arai, Tatsuo Korean Society of Photoscience 2014 Rapid communication in photoscience Vol.3 No.4

We studied the characteristics of emissive state of the first (p-G1) and second (p-G2) generation of phenylacetylene dendrimers bearing stilbene as a core by using time-resolved fluorescence spectroscopy in cyclohexane (c-Hex) and N, N-dimethylformide (DMF), which are nonpolar and polar solvents, respectively. Time-dependent red-shift of emission spectra p-G2 both in c-Hex and DMF was observed in comparison with p-G1. Besides, the time constant of red-shift of spectra was found to be larger in DMF than in c-Hex. This indicates that the emissive state of p-G2 has a polar character in DMF as a result of charge delocalization from core to peripheral dendrons followed by stabilization of emissive state.

Hydrogenation of Phenylacetylene to Styrene on Pre-C_xH_y- and C-Covered Cu(111) Single Crystal Catalysts

손영구,Wei Wei,John M. White 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.5

Thermal hydrogenation of phenylacetylene (PA, C_8H_6) to styrene (C_8H_8) on pre-C_xH_y- and C-covered Cu(111)single crystal substrates has been studied using temperature-programmed desorption (TPD) mass spectrometry. Chemisorbed PA with an acetylene group has been proved to be associated with hydrogen of pre-adsorbed C_xH_y to form styrene (104 amu) on Cu surface. For the parent (PA) mass (102 amu) TPD profile, the TPD peaks at 360 K and 410 K are assigned to chemisorbed vertically aligned PA and flat-lying cross-bridged PA,respectively (J. Phys. Chem. C 2007, 111, 5101). The relative I_(360K)/I_(410K) TPD ratio dramatically increases with increasing pre-adsorbed C_xH_y before dosing PA, while the ratio does not increase for pre-C-covered surface. For PA on pre-C_xH_y-covered Cu(111) surface, styrene desorption is enhanced relative to the parent PA desorption, while styrene formation is dramatically quenched on pre-C-covered (lack of adsorbed hydrogen nearby) surface. It appears that only cross-bridged PA associates with adsorbed hydrogen to form styrene that promptly desorbs at 410 K, while vertically aligned PA is less likely to participate in forming styrene.

Synthesis of Poly(phenylacetylene) Catalyzed by WCl6-EtAlCl2 and Its Electro-optical and Electrochemical Properties

Yeong-Soon Gal,Sung-Ho Jin,Sang Hee Jang,Kwon Taek Lim 한국화상학회 2011 한국화상학회지 Vol.17 No.3

WCl6-EtAlCl2 촉매계를 이용하여 비교적 큰 분자량을 갖는 폴리(페닐아세틸렌)을 합성하였다. 중합반응이 잘 진행되었으며 중합수율은 81%였다. 합성한 폴리(페닐아세틸렌) 분자구조를 NMR(1H-,13C-), IR, UV-visible, 원소분석 등으로 분석한 결과 페닐 치환기를 갖는 공액구조 고분자가 합성되었음을 확인할 수 있었다. 아울러 332 nm의 빛으로 여기시킬 경우 PL 최대 peak는 424 nm에서 관찰되었는데, 이는 2.93 eV의 광 에너지에 해당한다. 이 고분자의 순환 전압전류 그림은 도핑과 탈도핑사이에서 비가역적인 전기화학적 거동을 보여주었다. 이 고분자의 전기화학적 과정이 매우 안정하였으며, 스캔속도에 따른 산화전류 밀도 실험으로부터 이 고분자의 산화-환언 과정은 확산-제어과정에 따르는 것으로 분석되었다.

Hydrogenation of Phenylacetylene to Styrene on Pre-C_xH_y- and C-Covered Cu(111) Single Crystal Catalysts

Sohn, Young-Ku,Wei, Wei,White, John M. Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.5

Thermal hydrogenation of phenylacetylene (PA, $C_8H_6$) to styrene ($C_8H_8$) on pre-$C_xH_y$- and C-covered Cu(111) single crystal substrates has been studied using temperature-programmed desorption (TPD) mass spectrometry. Chemisorbed PA with an acetylene group has been proved to be associated with hydrogen of pre-adsorbed $C_xH_y$ to form styrene (104 amu) on Cu surface. For the parent (PA) mass (102 amu) TPD profile, the TPD peaks at 360 K and 410 K are assigned to chemisorbed vertically aligned PA and flat-lying cross-bridged PA, respectively (J. Phys. Chem. C 2007, 111, 5101). The relative $I_{360K}/I_{410K}$ TPD ratio dramatically increases with increasing pre-adsorbed $C_xH_y$ before dosing PA, while the ratio does not increase for pre-C-covered surface. For PA on pre-$C_xH_y$-covered Cu(111) surface, styrene desorption is enhanced relative to the parent PA desorption, while styrene formation is dramatically quenched on pre-C-covered (lack of adsorbed hydrogen nearby) surface. It appears that only cross-bridged PA associates with adsorbed hydrogen to form styrene that promptly desorbs at 410 K, while vertically aligned PA is less likely to participate in forming styrene.

Synthesis of Styryl-Terminated Silicon Quantum Dots: Reconsidering the Use of Methanol

Mai Xuan Dung,Hyun-Dam Jeong 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.12