Pub Date : 2024-10-24DOI: 10.1016/j.jcat.2024.115820
Andrew T.Y. Wolek , Evan Sowinski , Rajamani Gounder , Justin M. Notestein
Catalytic oligomerization of light olefins is an important CC coupling strategy that can be used to produce high-value transportation fuels and chemicals from shale gas and biomass feedstocks. In this work, vapor-phase propylene oligomerization was studied over a series of overcoated SiO2-MOx materials, whose acid site densities and strengths are tunable by the amount of SiO2 deposition and the nature of the core oxide. These materials contain acid sites only on particle external surfaces, limiting pore diffusion artifacts. SiO2-MOx materials were prepared by depositing stoichiometric amounts of tetraethyl orthosilicate (TEOS) onto Al2O3, anatase TiO2, Nb2O5, and ZrO2. Compared to the unmodified oxides, which are poor propylene oligomerization catalysts, the SiO2-MOx materials exhibit moderate activity with Al2O3, TiO2, and Nb2O5 core materials performing better than commercial amorphous silica alumina (ASA) on a surface area basis. The activity of the materials appears to be primarily driven by their Brønsted acid strength as measured by 31P TMPO MAS NMR with the rates ranked in order SiO2/Al2O3 > SiO2/TiO2 ≈ SiO2/Nb2O5 > SiO2/ZrO2. This study shows that SiO2-overcoated materials are a tunable class of materials that are active for vapor-phase propylene oligomerization.
{"title":"Propylene oligomerization over SiO2-overcoated oxides","authors":"Andrew T.Y. Wolek , Evan Sowinski , Rajamani Gounder , Justin M. Notestein","doi":"10.1016/j.jcat.2024.115820","DOIUrl":"10.1016/j.jcat.2024.115820","url":null,"abstract":"<div><div>Catalytic oligomerization of light olefins is an important C<img>C coupling strategy that can be used to produce high-value transportation fuels and chemicals from shale gas and biomass feedstocks. In this work, vapor-phase propylene oligomerization was studied over a series of overcoated SiO<sub>2</sub>-MOx materials, whose acid site densities and strengths are tunable by the amount of SiO<sub>2</sub> deposition and the nature of the core oxide. These materials contain acid sites only on particle external surfaces, limiting pore diffusion artifacts. SiO<sub>2</sub>-MOx materials were prepared by depositing stoichiometric amounts of tetraethyl orthosilicate (TEOS) onto Al<sub>2</sub>O<sub>3</sub>, anatase TiO<sub>2</sub>, Nb<sub>2</sub>O<sub>5</sub>, and ZrO<sub>2</sub>. Compared to the unmodified oxides, which are poor propylene oligomerization catalysts, the SiO<sub>2</sub>-MOx materials exhibit moderate activity with Al<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, and Nb<sub>2</sub>O<sub>5</sub> core materials performing better than commercial amorphous silica alumina (ASA) on a surface area basis. The activity of the materials appears to be primarily driven by their Brønsted acid strength as measured by <sup>31</sup>P TMPO MAS NMR with the rates ranked in order SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> > SiO<sub>2</sub>/TiO<sub>2</sub> ≈ SiO<sub>2</sub>/Nb<sub>2</sub>O<sub>5</sub> > SiO<sub>2</sub>/ZrO<sub>2</sub>. This study shows that SiO<sub>2</sub>-overcoated materials are a tunable class of materials that are active for vapor-phase propylene oligomerization.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115820"},"PeriodicalIF":6.5,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142489084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photo catalysis has comprehensively become a powerful tool in organic synthesis, and organic molecules are thriving as catalyst. The thioxanthone-TfOH complex (9-HTXTF) as photoredox catalyst with high oxidative capacity can be applied in single electron reduction of alkene affording alkene radical anion as a key intermediate. To transform this intermediate from radical anion to radical cation, a well-designed strategy is proposed with N-arylacrylamides as substrate. Based on its single electron transfer (SET) with 9-HTXTF*, N-radical cation is generated and then transformed to alkene radical cation by intramolecular conjugated system. By using this photoredox catalysis strategy, we developed a 9-HTXTF-catalyzed photochemical cyclization of alkenes, which further expands the applications of this catalyst. The entire cyclization is metal-free and without sacrificing agents, which conforms to atom economy and environmental friendliness.
{"title":"Generation of alkene radical cation for thioxanthone-TfOH complex-catalyzed intramolecular cyclization using a photoredox catalysis strategy","authors":"Jin Feng , Guanglong Huang , Haoliang Huang , Hanguang Tang , Wangsheng Liu , Aishun Ding , Xiao-Song Xue , Hao Guo","doi":"10.1016/j.jcat.2024.115817","DOIUrl":"10.1016/j.jcat.2024.115817","url":null,"abstract":"<div><div>Photo catalysis has comprehensively become a powerful tool in organic synthesis, and organic molecules are thriving as catalyst. The thioxanthone-TfOH complex (<strong>9-HTXTF</strong>) as photoredox catalyst with high oxidative capacity can be applied in single electron reduction of alkene affording alkene radical anion as a key intermediate. To transform this intermediate from radical anion to radical cation, a well-designed strategy is proposed with <em>N</em>-arylacrylamides as substrate. Based on its single electron transfer (SET) with <strong>9-HTXTF</strong>*, N-radical cation is generated and then transformed to alkene radical cation by intramolecular conjugated system. By using this photoredox catalysis strategy, we developed a <strong>9-HTXTF</strong>-catalyzed photochemical cyclization of alkenes, which further expands the applications of this catalyst. The entire cyclization is metal-free and without sacrificing agents, which conforms to atom economy and environmental friendliness.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115817"},"PeriodicalIF":6.5,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-22DOI: 10.1016/j.jcat.2024.115818
Bing-Bing Lu , Ji-Qiang Guan , Yu-Tong Wu , Si-Yi An , Ying Fu , Fei Ye
Boosting the nucleophilicity of Cu(I) sites is an essential strategy to enhance the efficiency of Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. In this work, a Lindquist-type polyoxometalate (POM)-based metal–organic framework, [CuI4(W6O19)2(L)]·2H2O (NEAU-1), was synthesized via an in-situ solvothermal method. Single-crystal X-ray diffraction results reveal that NEAU-1 exhibits a sandwich structure, with POMs intercalated between the two-dimensional layers formed by resorcin[4]arene ligands and Cu(I) ions. NEAU-1 possesses abundant Cu(I) active sites and high chemical stability, making it an effective heterogeneous catalyst for the CuAAC reaction. More importantly, the presence of POMs effectively reduces the electron cloud density around Cu(I) sites, significantly lowering the energy barrier for the formation of copper-acetylide compounds and facilitating subsequent nucleophilic reactions. The synergistic catalytic effect of POMs and Cu(I) can achieve a conversion rate of over 99 % for benzyl azide and phenylacetylene within 40 min. This work presents a sustainable molecular-level strategy to enhance the activity of the CuAAC reaction.
{"title":"Electron-withdrawing effect of polyoxometalates in Cu(I)-based metal–organic frameworks for enhanced azide-alkyne “click” reaction","authors":"Bing-Bing Lu , Ji-Qiang Guan , Yu-Tong Wu , Si-Yi An , Ying Fu , Fei Ye","doi":"10.1016/j.jcat.2024.115818","DOIUrl":"10.1016/j.jcat.2024.115818","url":null,"abstract":"<div><div>Boosting the nucleophilicity of Cu(I) sites is an essential strategy to enhance the efficiency of Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. In this work, a Lindquist-type polyoxometalate (POM)-based metal–organic framework, [Cu<sup>I</sup><sub>4</sub>(W<sub>6</sub>O<sub>19</sub>)<sub>2</sub>(L)]·2H<sub>2</sub>O (NEAU-1), was synthesized via an in-situ solvothermal method. Single-crystal X-ray diffraction results reveal that NEAU-1 exhibits a sandwich structure, with POMs intercalated between the two-dimensional layers formed by resorcin[4]arene ligands and Cu(I) ions. NEAU-1 possesses abundant Cu(I) active sites and high chemical stability, making it an effective heterogeneous catalyst for the CuAAC reaction. More importantly, the presence of POMs effectively reduces the electron cloud density around Cu(I) sites, significantly lowering the energy barrier for the formation of copper-acetylide compounds and facilitating subsequent nucleophilic reactions. The synergistic catalytic effect of POMs and Cu(I) can achieve a conversion rate of over 99 % for benzyl azide and phenylacetylene within 40 min. This work presents a sustainable molecular-level strategy to enhance the activity of the CuAAC reaction.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115818"},"PeriodicalIF":6.5,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142486829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-21DOI: 10.1016/j.jcat.2024.115815
Fengwei Zhang , Jijie Li , Shuai Chen , Jingjing Li , Ruimin Zhang , Yangyang Zhao , Wen-Yan Zan , Yawei Li
Transition metal-nitrogen-carbon (M−N−C) are considered as promising candidates for the electrochemical conversion of inert CO2 into high value-added CO products. However, previous reports have focused on Ni single-atom sites (Ni SAs) and the role of Ni nanoparticles (Ni NPs) in CO2 electroreduction reaction (CO2RR) has been overlooked. Herein, we prepared a series of Ni, N-codoped porous carbon (NiNC-T, T represents the temperature) catalysts by combining Ni phthalocyanine pyrolysis and acid etching strategy, which either contain only Ni SAs or both Ni SAs and Ni NPs. Notably, the NiNC-1100 catalyst with both Ni SAs and Ni NPs exhibited 99 % CO faradaic efficiency (FECO) at −0.66 V versus reversible hydrogen electrode (vs. RHE) and FECO above 98 % over a wide potential range (−0.66 V ∼ −1.06 V). Moreover, the FECO of NiNC-1100 remained above 95 % after 100 h of continuous electrocatalysis, which was significantly superior to that of the most advanced Ni single atom electrocatalysts. The systematic characterization results showed that the introduction of Ni NPs can promote the adsorption and activation of CO2 by increasing the electron cloud density of Ni SAs, thus enhancing the CO2RR catalytic performance.
过渡金属氮碳（M-N-C）被认为是将惰性二氧化碳电化学转化为高附加值一氧化碳产品的理想候选材料。然而，以往的报道主要集中于镍单原子位点（Ni SA），而镍纳米颗粒（Ni NPs）在 CO2 电还原反应（CO2RR）中的作用却被忽视了。在此，我们结合镍酞菁热解和酸蚀策略，制备了一系列镍、N-掺杂多孔碳（NiNC-T，T 代表温度）催化剂，这些催化剂或仅含有镍单原子位点，或同时含有镍单原子位点和镍纳米粒子。值得注意的是，同时含有 Ni SAs 和 Ni NPs 的 NiNC-1100 催化剂在 -0.66 V 相对于可逆氢电极（vs. RHE）时的 CO 法拉第效率（FECO）为 99%，在较宽的电位范围（-0.66 V ∼ -1.06 V）内的 FECO 均高于 98%。此外，在连续电催化 100 小时后，NiNC-1100 的 FECO 仍保持在 95% 以上，明显优于最先进的镍单原子电催化剂。系统表征结果表明，Ni NPs 的引入可以通过增加 Ni SAs 的电子云密度来促进 CO2 的吸附和活化，从而提高 CO2RR 催化性能。
{"title":"Highly stable and electron-rich Ni single atom catalyst for directed electroreduction of CO2 to CO","authors":"Fengwei Zhang , Jijie Li , Shuai Chen , Jingjing Li , Ruimin Zhang , Yangyang Zhao , Wen-Yan Zan , Yawei Li","doi":"10.1016/j.jcat.2024.115815","DOIUrl":"10.1016/j.jcat.2024.115815","url":null,"abstract":"<div><div>Transition metal-nitrogen-carbon (M−N−C) are considered as promising candidates for the electrochemical conversion of inert CO<sub>2</sub> into high value-added CO products. However, previous reports have focused on Ni single-atom sites (Ni SAs) and the role of Ni nanoparticles (Ni NPs) in CO<sub>2</sub> electroreduction reaction (CO<sub>2</sub>RR) has been overlooked. Herein, we prepared a series of Ni, N-codoped porous carbon (NiNC-T, T represents the temperature) catalysts by combining Ni phthalocyanine pyrolysis and acid etching strategy, which either contain only Ni SAs or both Ni SAs and Ni NPs. Notably, the NiNC-1100 catalyst with both Ni SAs and Ni NPs exhibited 99 % CO faradaic efficiency (FE<sub>CO</sub>) at −0.66 V versus reversible hydrogen electrode (<em>vs.</em> RHE) and FE<sub>CO</sub> above 98 % over a wide potential range (−0.66 V ∼ −1.06 V). Moreover, the FE<sub>CO</sub> of NiNC-1100 remained above 95 % after 100 h of continuous electrocatalysis, which was significantly superior to that of the most advanced Ni single atom electrocatalysts. The systematic characterization results showed that the introduction of Ni NPs can promote the adsorption and activation of CO<sub>2</sub> by increasing the electron cloud density of Ni SAs, thus enhancing the CO<sub>2</sub>RR catalytic performance.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115815"},"PeriodicalIF":6.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-21DOI: 10.1016/j.jcat.2024.115814
Qian Zheng , Yuandong Yan , Shaonan Zhang , Shicheng Yan , Zhigang Zou
Reducing the urea oxidation reaction (UOR) barriers is a key knot for accelerating its practical applications. Here, we demonstrate that NiMn-LDH with sulfate anion interaction can enable urea electrooxidation with a low anodic potential of 1.36 V at 100 mA cm−2. We find that the UOR on NiMn-LDH is driven by Ni3+ species and the Ni3+ generation is the rate-determining step of UOR. Both the Mn doping and sulfate anion interaction contribute to the low-barrier phase transformation from Ni(OH)2 to NiOOH to produce the Ni3+ state with high activity in UOR, owing to that Mn doping optimizes the electronic states and intercalation of guest anions weakens the interlayer interactions, which ultimately tunes Ni3+ generation kinetics toward the superior UOR activity. Our findings provide new insights into the design of the highly active UOR catalysts.
{"title":"Anion intercalation of NiMn-LDH accelerating urea electrooxidation on trivalent nickel","authors":"Qian Zheng , Yuandong Yan , Shaonan Zhang , Shicheng Yan , Zhigang Zou","doi":"10.1016/j.jcat.2024.115814","DOIUrl":"10.1016/j.jcat.2024.115814","url":null,"abstract":"<div><div>Reducing the urea oxidation reaction (UOR) barriers is a key knot for accelerating its practical applications. Here, we demonstrate that NiMn-LDH with sulfate anion interaction can enable urea electrooxidation with a low anodic potential of 1.36 V at 100 mA cm<sup>−2</sup>. We find that the UOR on NiMn-LDH is driven by Ni<sup>3+</sup> species and the Ni<sup>3+</sup> generation is the rate-determining step of UOR. Both the Mn doping and sulfate anion interaction contribute to the low-barrier phase transformation from Ni(OH)<sub>2</sub> to NiOOH to produce the Ni<sup>3+</sup> state with high activity in UOR, owing to that Mn doping optimizes the electronic states and intercalation of guest anions weakens the interlayer interactions, which ultimately tunes Ni<sup>3+</sup> generation kinetics toward the superior UOR activity. Our findings provide new insights into the design of the highly active UOR catalysts.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115814"},"PeriodicalIF":6.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-21DOI: 10.1016/j.jcat.2024.115816
Tuani C. Gentil , Maria Minichova , Valentín Briega-Martos , Victor S. Pinheiro , Felipe M. Souza , João Paulo C. Moura , Júlio César M. Silva , Bruno L. Batista , Mauro C. Santos , Serhiy Cherevko
This study evaluates the dissolution of the supported electrocatalysts Pd/C, PdSn/C, PdNb/C, and PdFe3O4/C during ethanol oxidation reaction for Alkaline Direct Liquid Fuel Cells (ADLFC) applications. A scanning flow cell (SFC) combined to an inductively coupled plasma mass spectrometry (online ICP-MS) is used to assess the dissolution stability in a broad potential window. Accelerated stress tests with and without ethanol are developed using a rotating disk electrode (RDE) with dissolution products analysis by ex-situ ICP-MS. Potential profiles simulating those experienced by the catalyst during regular fuel cell operation were used. Sn and Fe catalysts demonstrate improved activity and stability compared with the material with Pd alone. For these reasons, PdSn/C and PdFe3O4/C are suitable for ADLFC applications. Severe Nb dissolution destabilizes Pd, increasing its leaching. This work demonstrates that while additional metals and oxides can improve the alcohol oxidation kinetics of Pd, these additives’ dissolution stability must already be considered at the catalyst design stage.
{"title":"Stability of supported Pd-based ethanol oxidation reaction electrocatalysts in alkaline media","authors":"Tuani C. Gentil , Maria Minichova , Valentín Briega-Martos , Victor S. Pinheiro , Felipe M. Souza , João Paulo C. Moura , Júlio César M. Silva , Bruno L. Batista , Mauro C. Santos , Serhiy Cherevko","doi":"10.1016/j.jcat.2024.115816","DOIUrl":"10.1016/j.jcat.2024.115816","url":null,"abstract":"<div><div>This study evaluates the dissolution of the supported electrocatalysts Pd/C, PdSn/C, PdNb/C, and PdFe<sub>3</sub>O<sub>4</sub>/C during ethanol oxidation reaction for Alkaline Direct Liquid Fuel Cells (ADLFC) applications. A scanning flow cell (SFC) combined to an inductively coupled plasma mass spectrometry (online ICP-MS) is used to assess the dissolution stability in a broad potential window. Accelerated stress tests with and without ethanol are developed using a rotating disk electrode (RDE) with dissolution products analysis by ex-situ ICP-MS. Potential profiles simulating those experienced by the catalyst during regular fuel cell operation were used. Sn and Fe catalysts demonstrate improved activity and stability compared with the material with Pd alone. For these reasons, PdSn/C and PdFe<sub>3</sub>O<sub>4</sub>/C are suitable for ADLFC applications. Severe Nb dissolution destabilizes Pd, increasing its leaching. This work demonstrates that while additional metals and oxides can improve the alcohol oxidation kinetics of Pd, these additives’ dissolution stability must already be considered at the catalyst design stage.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115816"},"PeriodicalIF":6.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
From the perspectives of innovation and broad-spectrum, tubular carbon nitride-based photocatalyst, viz., Ag/AgI/g-C3N4 S-scheme heterojunction photocatalyst, with enhancement of nitrogen vacancy and localized surface plasmon resonance (LSPR) effect is reasonably devised and manufactured via combining hydrothermal, calcination and photo-reduction techniques. The optimal specimen displays high photocatalytic activity in removal of dyes [such as crystal violet (CV), 100.00 %/60 min], antibiotics [such as levofloxacin (LEV), 88.72 %/50 min] and Cr(VI) (100.00 %, 30 min), photocatalytic hydrogen evolution (1023.3 μmol h−1 g−1) and H2O2 generation (866.2 μmol h−1 g−1), achieving broad-spectrum natures, viz., realizing the function of “one stone five birds”. The broad-spectrum natures are attributed to the synergisms of nitrogen vacancy, LSPR effect of Ag, hollow tube structure and S-scheme heterojunction, which facilitate the separation and migration of photo-generated carriers and inject “hot electrons” generated by Ag into the conduction band of Ag/AgI/g-C3N4, increase the specific surface area and broaden the spectral response range. Further, the degraded intermediates of CV and LEV and possible degradation pathways are rationally advanced by the aid of LCMS spectra, the predicted toxicity of degraded intermediates of LEV is assessed by Toxicity Estimation Software (T.E.S.T.), and the biotoxicity of CV, LEV and Cr(VI) solutions after photocatalytic degradation is further assessed by feat of cultivate rice. Synergistically enhanced photocatalytic mechanism of Ag/AgI/g-C3N4 hollow tube S-scheme heterojunction is confirmed based upon a series of sound experiments, fs-TA spectra, in-situ XPS and DFT calculation, etc.
{"title":"Plasmon and N-vacancy synergistically enhanced tubular carbon nitride-based S-scheme heterojunction photocatalyst with one stone five birds function: Pathways, DFT calculation and mechanism insight","authors":"Feng Sun, Qian Xu, Haiyang Liu, Da Xu, Xinxing Wang, Chuan Luo, Tianqi Wang, Hui Yu, Wensheng Yu, Xiangting Dong","doi":"10.1016/j.jcat.2024.115813","DOIUrl":"10.1016/j.jcat.2024.115813","url":null,"abstract":"<div><div>From the perspectives of innovation and broad-spectrum, tubular carbon nitride-based photocatalyst, <em>viz.</em>, Ag/AgI/g-C<sub>3</sub>N<sub>4</sub> S-scheme heterojunction photocatalyst, with enhancement of nitrogen vacancy and localized surface plasmon resonance (LSPR) effect is reasonably devised and manufactured <em>via</em> combining hydrothermal, calcination and photo-reduction techniques. The optimal specimen displays high photocatalytic activity in removal of dyes [such as crystal violet (CV), 100.00 %/60 min], antibiotics [such as levofloxacin (LEV), 88.72 %/50 min] and Cr(VI) (100.00 %, 30 min), photocatalytic hydrogen evolution (1023.3 μmol h<sup>−1</sup> g<sup>−1</sup>) and H<sub>2</sub>O<sub>2</sub> generation (866.2 μmol h<sup>−1</sup> g<sup>−1</sup>), achieving broad-spectrum natures, <em>viz.</em>, realizing the function of “one stone five birds”. The broad-spectrum natures are attributed to the synergisms of nitrogen vacancy, LSPR effect of Ag, hollow tube structure and S-scheme heterojunction, which facilitate the separation and migration of photo-generated carriers and inject “hot electrons” generated by Ag into the conduction band of Ag/AgI/g-C<sub>3</sub>N<sub>4</sub>, increase the specific surface area and broaden the spectral response range. Further, the degraded intermediates of CV and LEV and possible degradation pathways are rationally advanced by the aid of LCMS spectra, the predicted toxicity of degraded intermediates of LEV is assessed by Toxicity Estimation Software (T.E.S.T.), and the biotoxicity of CV, LEV and Cr(VI) solutions after photocatalytic degradation is further assessed by feat of cultivate rice. Synergistically enhanced photocatalytic mechanism of Ag/AgI/g-C<sub>3</sub>N<sub>4</sub> hollow tube S-scheme heterojunction is confirmed based upon a series of sound experiments, fs-TA spectra, in-situ XPS and DFT calculation, <em>etc</em>.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115813"},"PeriodicalIF":6.5,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142452588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-20DOI: 10.1016/j.jcat.2024.115812
Guoqiang Zhao , Xiangchao Xu , Jin Zhang , Beixuan Dong , Wenli Wang , Wenbo Zhou , Qixun Shi , Feng Li
The 1,6-conjugate hydrogenation of para-quinone methides to diaryl- and triarylmethanes under atmospheric pressure has been proposed and accomplished. In the presence of [Cp*Ir(2,2′-bpyO)(H2O)] (0.5 mol %), a range of desirable products were obtained in high yields. Functional groups in bpy ligand were found to be crucially important for the catalytic activity of iridium complexes. Furthermore, the practical application of the present catalytic system was also presented.
{"title":"1,6-Conjugate hydrogenation of para-quinone methides to phenol-containing diaryl- and triarylmethanes under atmospheric pressure catalyzed by a metal–ligand bifunctional iridium catalyst","authors":"Guoqiang Zhao , Xiangchao Xu , Jin Zhang , Beixuan Dong , Wenli Wang , Wenbo Zhou , Qixun Shi , Feng Li","doi":"10.1016/j.jcat.2024.115812","DOIUrl":"10.1016/j.jcat.2024.115812","url":null,"abstract":"<div><div>The 1,6-conjugate hydrogenation of <em>para</em>-quinone methides to diaryl- and triarylmethanes under atmospheric pressure has been proposed and accomplished. In the presence of [Cp*Ir(2,2′-bpyO)(H<sub>2</sub>O)] (0.5 mol %), a range of desirable products were obtained in high yields. Functional groups in bpy ligand were found to be crucially important for the catalytic activity of iridium complexes. Furthermore, the practical application of the present catalytic system was also presented.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115812"},"PeriodicalIF":6.5,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Smaller nano-sizes typically result in supported catalysts with abundant interfacial and intrinsic oxygen vacancies for better adsorption and activation of small molecules, including CO2, leading to improved efficiency of CO2 methanation. Here, Ni/CeO2-S with the smaller nano-size of around 4.2 nm is used to catalyze CO2 methanation, which exhibits significantly enhanced activity compared to larger nano-sized Ni/CeO2-L catalyst, even surpassing the most majority of previously reported catalysts using CeO2 as the support or Ni as the active metal. The coexistence of interfacial defects and intrinsic oxygen vacancies allows for enhanced adsorption and activation of CO2 molecules as well as H spillover, resulting in such improved CO2 methanation. In-situ DRIFTS demonstrate a nearly sole Formate pathway on Ni/CeO2-S for efficient CO2 hydrogenation. This research provides valuable insights into the reaction mechanism over a small nanosize supported catalyst.
较小尺寸的纳米催化剂通常具有丰富的界面空位和固有氧空位，可更好地吸附和活化包括 CO2 在内的小分子，从而提高 CO2 甲烷化的效率。本文采用纳米尺寸较小（约 4.2 纳米）的 Ni/CeO2-S 催化 CO2 甲烷化，与较大纳米尺寸的 Ni/CeO2-L 催化剂相比，其活性显著提高，甚至超过了之前报道的大多数以 CeO2 为载体或以 Ni 为活性金属的催化剂。界面缺陷和内在氧空位的共存增强了 CO2 分子的吸附和活化以及 H 的溢出，从而提高了 CO2 的甲烷化。原位 DRIFTS 显示，Ni/CeO2-S 上几乎只有一种甲酸盐途径可实现高效的 CO2 加氢。这项研究为了解小尺寸纳米支撑催化剂的反应机理提供了宝贵的见解。
{"title":"Abundant interfacial and intrinsic oxygen vacancies enabling small nickel/ceria nanocrystal efficient CO2 methanation","authors":"Chaoyang Yang, Junlei Zhang, Weiping Liu, Xueyi Yang, Yuwen Wang, Wanglei Wang","doi":"10.1016/j.jcat.2024.115811","DOIUrl":"10.1016/j.jcat.2024.115811","url":null,"abstract":"<div><div>Smaller nano-sizes typically result in supported catalysts with abundant interfacial and intrinsic oxygen vacancies for better adsorption and activation of small molecules, including CO<sub>2</sub>, leading to improved efficiency of CO<sub>2</sub> methanation. Here, Ni/CeO<sub>2</sub>-S with the smaller nano-size of around 4.2 nm is used to catalyze CO<sub>2</sub> methanation, which exhibits significantly enhanced activity compared to larger nano-sized Ni/CeO<sub>2</sub>-L catalyst, even surpassing the most majority of previously reported catalysts using CeO<sub>2</sub> as the support or Ni as the active metal. The coexistence of interfacial defects and intrinsic oxygen vacancies allows for enhanced adsorption and activation of CO<sub>2</sub> molecules as well as H spillover, resulting in such improved CO<sub>2</sub> methanation. <em>In-situ</em> DRIFTS demonstrate a nearly sole Formate pathway on Ni/CeO<sub>2</sub>-S for efficient CO<sub>2</sub> hydrogenation. This research provides valuable insights into the reaction mechanism over a small nanosize supported catalyst.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115811"},"PeriodicalIF":6.5,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142450150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-19DOI: 10.1016/j.jcat.2024.115790
Xinyu Yao , Dong Liu , Junhong Fu , Jian Wang , Mengle Shen , Zuoyi Xiao , Qingda An , Jiahui Huang
Due to easy dehydration of La(OH)3 to LaOOH by thermal treatment, it is challenging to prepare highly efficient Ni/La(OH)3 catalyst for hydrogenolysis reactions. Herein, Ni/La(OH)3 (Ni/La-2) catalyst is prepared by thermal reduction of NiO/La(OH)3 in hydrogen flow with vaporized water, while La(OH)3 is partially dehydrated to LaOOH without water vapor affording Ni/(La(OH)3 + LaOOH) (Ni/La-1). Ni/La-2 displays 93 % and 3 % yields of 1,2,6-hexanetriol (HTO) and 1,6-hexanediol (HDO) respectively towards C-O hydrogenolysis of tetrahydrofuran-dimethanol (THFDM) in batch reactor and high stability (200 h) in fixed-bed reactor, which is the best among the reported catalysts to the best of our knowledge. Ni/La-2 possesses pure La(OH)3 as support, enhanced dispersion of Ni species and abundant Niδ+-O-La interfaces in comparison to Ni/La-1, which results in the exceptional catalytic performances in C-O hydrogenolysis of THFDM. A fine control of reaction temperature and time is required to optimize the yields HTO and HDO in hydrogenolysis of THFDM over Ni/La-2. The water-assisted preparation method provides a new perspective for the preparation of La(OH)3 supported metal catalysts.
{"title":"Water-assisted preparation of Ni/La(OH)3 catalyst for efficient catalytic C-O bond hydrogenolysis of tetrahydrofuran-dimethanol","authors":"Xinyu Yao , Dong Liu , Junhong Fu , Jian Wang , Mengle Shen , Zuoyi Xiao , Qingda An , Jiahui Huang","doi":"10.1016/j.jcat.2024.115790","DOIUrl":"10.1016/j.jcat.2024.115790","url":null,"abstract":"<div><div>Due to easy dehydration of La(OH)<sub>3</sub> to LaOOH by thermal treatment, it is challenging to prepare highly efficient Ni/La(OH)<sub>3</sub> catalyst for hydrogenolysis reactions. Herein, Ni/La(OH)<sub>3</sub> (Ni/La-2) catalyst is prepared by thermal reduction of NiO/La(OH)<sub>3</sub> in hydrogen flow with vaporized water, while La(OH)<sub>3</sub> is partially dehydrated to LaOOH without water vapor affording Ni/(La(OH)<sub>3</sub> + LaOOH) (Ni/La-1). Ni/La-2 displays 93 % and 3 % yields of 1,2,6-hexanetriol (HTO) and 1,6-hexanediol (HDO) respectively towards C-O hydrogenolysis of tetrahydrofuran-dimethanol (THFDM) in batch reactor and high stability (200 h) in fixed-bed reactor, which is the best among the reported catalysts to the best of our knowledge. Ni/La-2 possesses pure La(OH)<sub>3</sub> as support, enhanced dispersion of Ni species and abundant Ni<sup>δ+</sup>-O-La interfaces in comparison to Ni/La-1, which results in the exceptional catalytic performances in C-O hydrogenolysis of THFDM. A fine control of reaction temperature and time is required to optimize the yields HTO and HDO in hydrogenolysis of THFDM over Ni/La-2. The water-assisted preparation method provides a new perspective for the preparation of La(OH)<sub>3</sub> supported metal catalysts.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115790"},"PeriodicalIF":6.5,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142450207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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