Microwave-assisted catalysis is a promising technique for enhancing catalytic reactions through selective heating, potentially leading to improved reaction rates and energy efficiency. However, understanding the complex interactions between microwave absorption and catalytic performance in composite catalysts remains a challenge. In this study, Cobalt oxide(CoO)/silicon carbide(SiC) composite catalysts with varying SiC content were synthesized and characterized to investigate the relationship between their microwave absorption properties and catalytic performance. Quantitative analysis revealed that SiC and CoO absorb microwave energy through relaxation polarization and magnetic loss mechanisms, respectively. Increasing SiC content enhanced the dielectric and magnetic loss capabilities of the composites, with the CoO/SiC composite containing 10 wt% SiC (CoO/SiC-10) exhibiting a dielectric loss tangent of 3.87 and a minimum reflection loss of −35dB. However, higher SiC content decreased the surface chemically adsorbed oxygen, surface oxygen mobility, and benzene adsorption capacity, weakening the catalytic activity under conventional heating. The CoO/SiC-10 sample achieved a significantly better balance between microwave absorption and catalytic performance, significantly outperforming the original CoO sample under microwave irradiation. These founding establishes a quantitative research methodology that correlates dielectric loss tangent, reflection loss, and other crucial parameters with microwave absorption performance and further catalytic properties, providing insights for the rational design of catalysts that optimize both microwave absorption and catalytic activity.
微波辅助催化是一种很有前途的技术，可通过选择性加热提高催化反应，从而提高反应速率和能效。然而，了解复合催化剂中微波吸收与催化性能之间复杂的相互作用仍然是一项挑战。本研究合成并表征了不同碳化硅含量的氧化钴（CoO）/碳化硅（SiC）复合催化剂，以研究其微波吸收特性与催化性能之间的关系。定量分析发现，SiC 和 CoO 分别通过弛豫极化和磁损耗机制吸收微波能量。提高 SiC 含量可增强复合材料的介电损耗和磁损耗能力，含 10 wt% SiC 的 CoO/SiC 复合材料（CoO/SiC-10）的介电损耗正切为 3.87，最小反射损耗为 -35dB。然而，较高的 SiC 含量会降低表面化学吸附氧、表面氧迁移率和苯吸附能力，从而削弱常规加热条件下的催化活性。CoO/SiC-10 样品在微波吸收和催化性能之间取得了更好的平衡，在微波辐照下明显优于原始 CoO 样品。这些研究成果建立了一种定量研究方法，将介质损耗正切、反射损耗和其他关键参数与微波吸收性能和进一步的催化性能联系起来，为合理设计同时优化微波吸收和催化活性的催化剂提供了启示。
{"title":"Synergistic SiC/Co3O4 composites for enhanced microwave-assisted benzene catalytic removal performance","authors":"Zhi Jiang, DongXu Fang, Haolin Luo, Zheng Ye, Hua Li, Wenfeng Shangguan","doi":"10.1016/j.mtchem.2024.102243","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102243","url":null,"abstract":"Microwave-assisted catalysis is a promising technique for enhancing catalytic reactions through selective heating, potentially leading to improved reaction rates and energy efficiency. However, understanding the complex interactions between microwave absorption and catalytic performance in composite catalysts remains a challenge. In this study, Cobalt oxide(CoO)/silicon carbide(SiC) composite catalysts with varying SiC content were synthesized and characterized to investigate the relationship between their microwave absorption properties and catalytic performance. Quantitative analysis revealed that SiC and CoO absorb microwave energy through relaxation polarization and magnetic loss mechanisms, respectively. Increasing SiC content enhanced the dielectric and magnetic loss capabilities of the composites, with the CoO/SiC composite containing 10 wt% SiC (CoO/SiC-10) exhibiting a dielectric loss tangent of 3.87 and a minimum reflection loss of −35dB. However, higher SiC content decreased the surface chemically adsorbed oxygen, surface oxygen mobility, and benzene adsorption capacity, weakening the catalytic activity under conventional heating. The CoO/SiC-10 sample achieved a significantly better balance between microwave absorption and catalytic performance, significantly outperforming the original CoO sample under microwave irradiation. These founding establishes a quantitative research methodology that correlates dielectric loss tangent, reflection loss, and other crucial parameters with microwave absorption performance and further catalytic properties, providing insights for the rational design of catalysts that optimize both microwave absorption and catalytic activity.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"33 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-17DOI: 10.1016/j.mtchem.2024.102248
Ana Laura M.M. Alves, Francisco V. dos Santos, Daniel S. Correa
The escalating challenge of water resources contamination, attributed to toxic pollutants, requires urgent attention from both governments and society. Furthermore, the inefficacy of conventional water treatment methods emphasizes the critical necessity for exploring the development of affordable, renewable, and high-performance materials, which should, for instance, enable the mutual adsorption and photocatalytic degradation of organic pollutants. Here we employed the 3D printing technique to manufacture an aerogel based on alginate, gelatin, and carboxymethylcellulose incorporated with 5 and 7.5 wt % of MOF/MoS. FTIR spectra and EDS analysis evidenced the presence of MOF/MoS in the structure of the aerogels, while Helium pycnometer analysis and SEM micrographs demonstrated that the aerogels presented low density and a porous structure with porosity above 80 %. The swelling test showed that the aerogels displayed a high water absorption capacity (1400 %) after 70 h of immersion. The rheology test demonstrated that elastic behavior prevails over viscous behavior (G' > G″) and the incorporation of 7.5 wt % MOF/MoS favored shear thinning and viscosity recovery in the hydrogel. Adsorption tests to methylene blue (employed as a model) showed that the aerogel (HD) without the presence of MOF/MoS and the aerogels HD/MOF/MoS 5 % and MOF/MoS 7.5 % showed removal efficiencies of 16.77 %, 28.66 %, and 95.86 %, respectively. Conversely, the photodegradation test showed that HD/MOF/MoS 5 % and HD/MOF/MoS 7.5 % had an efficiency of 89 % and HD of 80 %. Therefore, our results demonstrate that the developed aerogels are promising candidates for the adsorption and photodegradation of dye while being low-cost, environmentally friendly, and easy to manufacture.
{"title":"3D-printed MOF/MoS2 aerogel for dye adsorption and photocatalytic degradation","authors":"Ana Laura M.M. Alves, Francisco V. dos Santos, Daniel S. Correa","doi":"10.1016/j.mtchem.2024.102248","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102248","url":null,"abstract":"The escalating challenge of water resources contamination, attributed to toxic pollutants, requires urgent attention from both governments and society. Furthermore, the inefficacy of conventional water treatment methods emphasizes the critical necessity for exploring the development of affordable, renewable, and high-performance materials, which should, for instance, enable the mutual adsorption and photocatalytic degradation of organic pollutants. Here we employed the 3D printing technique to manufacture an aerogel based on alginate, gelatin, and carboxymethylcellulose incorporated with 5 and 7.5 wt % of MOF/MoS. FTIR spectra and EDS analysis evidenced the presence of MOF/MoS in the structure of the aerogels, while Helium pycnometer analysis and SEM micrographs demonstrated that the aerogels presented low density and a porous structure with porosity above 80 %. The swelling test showed that the aerogels displayed a high water absorption capacity (1400 %) after 70 h of immersion. The rheology test demonstrated that elastic behavior prevails over viscous behavior (G' > G″) and the incorporation of 7.5 wt % MOF/MoS favored shear thinning and viscosity recovery in the hydrogel. Adsorption tests to methylene blue (employed as a model) showed that the aerogel (HD) without the presence of MOF/MoS and the aerogels HD/MOF/MoS 5 % and MOF/MoS 7.5 % showed removal efficiencies of 16.77 %, 28.66 %, and 95.86 %, respectively. Conversely, the photodegradation test showed that HD/MOF/MoS 5 % and HD/MOF/MoS 7.5 % had an efficiency of 89 % and HD of 80 %. Therefore, our results demonstrate that the developed aerogels are promising candidates for the adsorption and photodegradation of dye while being low-cost, environmentally friendly, and easy to manufacture.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"41 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A shortage of long-term stability of electrochromic materials has been hindering their practical application. A series of novel polyamides (PAs) (4) with five electroactive nitrogen atoms within triphenylamine (TPA)-containing structures was synthesized via phosphorylation polyamidation. Polyamide 4 exhibited highly integrated electrochromic performances, including multiple color changes, high contrast of optical transmittance change, and the highest electrochromic stability (only 11.2 and 9.6 % decay of its coloration efficiency (CE) at 450 nm after 50000 and 16000 switching cycles, respectively) compared to all other triarylamine-based polymers to date. This record-high electrochromic cycling is attributed to the enhanced stability of polaron, which was studied through the electron-donating or electron-withdrawing effect of substituents and the resonance effect of electron delocalization over the electroactive nitrogen centers. Importantly, our core design of five electroactive nitrogen centers with electron-donating methoxy groups is the key factor to increase stability of polaron in the resulting polymers 4. More electroactive nitrogen centers are able to create a weaker electronic coupling due to a charge of cation radical dispersed by resonance successfully in-between the different redox states, which is evidenced clearly by the observed longer wavelength absorption in the NIR region. Our research confirms that the key to determining polaron stability is the resonance by the electrons delocalized over all the redox centers, rather than the electronic coupling between the different redox centers. And the resonance leads to increasing electrochromic stability of the polymer.
{"title":"Achieving ultrahigh electrochromic stability of triarylamine-based polymers by the design of five electroactive nitrogen centers","authors":"Yaw-Terng Chern, Yu-Quan Lin, Jia-Rong Han, Yu-Cheng Chiu","doi":"10.1016/j.mtchem.2024.102236","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102236","url":null,"abstract":"A shortage of long-term stability of electrochromic materials has been hindering their practical application. A series of novel polyamides (PAs) (4) with five electroactive nitrogen atoms within triphenylamine (TPA)-containing structures was synthesized via phosphorylation polyamidation. Polyamide 4 exhibited highly integrated electrochromic performances, including multiple color changes, high contrast of optical transmittance change, and the highest electrochromic stability (only 11.2 and 9.6 % decay of its coloration efficiency (CE) at 450 nm after 50000 and 16000 switching cycles, respectively) compared to all other triarylamine-based polymers to date. This record-high electrochromic cycling is attributed to the enhanced stability of polaron, which was studied through the electron-donating or electron-withdrawing effect of substituents and the resonance effect of electron delocalization over the electroactive nitrogen centers. Importantly, our core design of five electroactive nitrogen centers with electron-donating methoxy groups is the key factor to increase stability of polaron in the resulting polymers 4. More electroactive nitrogen centers are able to create a weaker electronic coupling due to a charge of cation radical dispersed by resonance successfully in-between the different redox states, which is evidenced clearly by the observed longer wavelength absorption in the NIR region. Our research confirms that the key to determining polaron stability is the resonance by the electrons delocalized over all the redox centers, rather than the electronic coupling between the different redox centers. And the resonance leads to increasing electrochromic stability of the polymer.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"4 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water electrolysis is a promising, carbonless technology for hydrogen production, however, its widely industrial application is severely limited by the extensive energy consumption caused by sluggish oxygen evolution reaction (OER) kinetics. Herein, the simple Mn doping is employed to finely tune sulfur vacancies (V). The thoeretic calculations prove that the electron structure has been well controlled. Compared with perfect MoS (without V), the electron re-distribution of Mn-doped MoS with V (Vs-Mn-MoS) exhibits the both modes: electron depletion near the V and electron accumulation between two Mo atoms. Furthermore, the well-controlled electron structure obviously promotes H adsorption. The experimental results shows that the 5 wt% Mn–MoS exhibits an excellent hydrogen evolution reaction (HER) activity (79 mV/10 mA cm, 55.46 mV dec), which is better than the other MoS-based electrolysts in the previous reports. Moreover, an innovative substitution anode reaction is designed, namely, glycerol oxidation reaction (GOR)-based symmetric electrolyser with Mn–MoS as the both electrodes. At 60 mA cm, the cell voltage of GOR-based electrolyser has decreased by 14.8 %, and its Faradaic efficiency for HER increases by 10.04 % compared to conventional water-based one. This result proves that about 14.8 % of electric energy can be economized. Thus, this innovative electrocatalysis system could be promising for industrial hydrogen production.
水电解是一种前景广阔的无碳制氢技术，但由于氧进化反应（OER）动力学缓慢，导致能耗过大，从而严重限制了其在工业上的广泛应用。本文采用简单的锰掺杂来微调硫空位（V）。热力学计算证明，电子结构得到了很好的控制。与完美的 MoS（不含 V）相比，掺有锰的 MoS（Vs-Mn-MoS）的电子再分布表现出两种模式：V 附近的电子耗尽和两个 Mo 原子间的电子积聚。此外，良好的电子结构明显促进了 H 的吸附。实验结果表明，5 wt% 的锰-MoS 具有优异的氢进化反应（HER）活性（79 mV/10 mA cm, 55.46 mV dec），优于之前报道的其他 MoS 基电解质。此外，还设计了一种创新的置换阳极反应，即以 Mn-MoS 为两极的基于甘油氧化反应（GOR）的对称电解槽。与传统的水基电解槽相比，在 60 mA cm 的条件下，甘油氧化反应电解槽的电池电压降低了 14.8%，其 HER 的法拉第效率提高了 10.04%。这一结果证明可以节省约 14.8% 的电能。因此，这种创新的电催化系统在工业制氢方面大有可为。
{"title":"Effect of electron redistribution on H adsorption and hydrogen production efficiency","authors":"Wansheng Ruan, Yiran Teng, Hanming Zhang, Zhihui Li, Tongguang Xu, Yalin Yang, Fei Teng","doi":"10.1016/j.mtchem.2024.102244","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102244","url":null,"abstract":"Water electrolysis is a promising, carbonless technology for hydrogen production, however, its widely industrial application is severely limited by the extensive energy consumption caused by sluggish oxygen evolution reaction (OER) kinetics. Herein, the simple Mn doping is employed to finely tune sulfur vacancies (V). The thoeretic calculations prove that the electron structure has been well controlled. Compared with perfect MoS (without V), the electron re-distribution of Mn-doped MoS with V (Vs-Mn-MoS) exhibits the both modes: electron depletion near the V and electron accumulation between two Mo atoms. Furthermore, the well-controlled electron structure obviously promotes H adsorption. The experimental results shows that the 5 wt% Mn–MoS exhibits an excellent hydrogen evolution reaction (HER) activity (79 mV/10 mA cm, 55.46 mV dec), which is better than the other MoS-based electrolysts in the previous reports. Moreover, an innovative substitution anode reaction is designed, namely, glycerol oxidation reaction (GOR)-based symmetric electrolyser with Mn–MoS as the both electrodes. At 60 mA cm, the cell voltage of GOR-based electrolyser has decreased by 14.8 %, and its Faradaic efficiency for HER increases by 10.04 % compared to conventional water-based one. This result proves that about 14.8 % of electric energy can be economized. Thus, this innovative electrocatalysis system could be promising for industrial hydrogen production.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"19 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Donor-acceptor thermally activated delayed fluorescent (TADF) materials have been widely used in photocatalytic reactions as organic photosensitizers. However, the construction of TADF photosensitizers via a supramolecular self-assembly approach with the regulation of reactive oxygen species (ROS) is still a big challenge. In this study, a TADF molecule 4,4'-(6-(pyridin-4-yl)quinoxaline-2,3-diyl)bis(,-diphenylaniline) (TPA-PQ) by incorporating triphenylamine (TPA) act as donor and 6-(pyridin-4-yl)quinoxaline (PQ) act as an acceptor was designed and synthesized, which exhibited excellent TADF property and strong intramolecular charge transfer. Meanwhile, the TPA-PQ can not only self-assemble to form nanofiber structure in mixed solvent of HO and THF, but also can be used as a type I photosensitizer to selectively produce superoxide anion radicals (O). More interestingly, the ROS generated from TPA-PQ can be used as photocatalysts for the oxidative hydroxylation of arylboronic acids and aerobic cross dehydrogenation coupling (CDC) reactions with high yields of 92 % and 88 %, respectively. This study presents an innovative and eco-friendly approach to utilize TADF supramolecular structures for the purpose of conducting photocatalyzed organic reactions.
作为有机光敏剂，供体-受体热激活延迟荧光（TADF）材料已被广泛应用于光催化反应中。然而，如何通过超分子自组装方法构建具有活性氧（ROS）调控作用的 TADF 光敏剂仍然是一个巨大的挑战。本研究以三苯胺（TPA）为供体，以6-(吡啶-4-基)喹喔啉（PQ）为受体，设计合成了4,4'-(6-(吡啶-4-基)喹喔啉-2,3-二基)双(,-二苯基苯胺)（TPA-PQ）TADF分子。同时，TPA-PQ 不仅能在 HO 和 THF 混合溶剂中自组装形成纳米纤维结构，还能作为 I 型光敏剂选择性地产生超氧阴离子自由基（O）。更有趣的是，TPA-PQ 产生的 ROS 可用作光催化剂，用于芳基硼酸的氧化羟基化和有氧交叉脱氢偶联（CDC）反应，产率分别高达 92% 和 88%。这项研究提出了一种利用 TADF 超分子结构进行光催化有机反应的创新性环保方法。
{"title":"Pyrazine-based supramolecular photosensitizing assemblies as type I photosensitizers for high-efficiency photooxidation reactions","authors":"Xiao-Han Shi, Rui-Zhi Dong, Kai-Kai Niu, Hui Liu, Shengsheng Yu, Ling-Bao Xing","doi":"10.1016/j.mtchem.2024.102249","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102249","url":null,"abstract":"Donor-acceptor thermally activated delayed fluorescent (TADF) materials have been widely used in photocatalytic reactions as organic photosensitizers. However, the construction of TADF photosensitizers via a supramolecular self-assembly approach with the regulation of reactive oxygen species (ROS) is still a big challenge. In this study, a TADF molecule 4,4'-(6-(pyridin-4-yl)quinoxaline-2,3-diyl)bis(,-diphenylaniline) (TPA-PQ) by incorporating triphenylamine (TPA) act as donor and 6-(pyridin-4-yl)quinoxaline (PQ) act as an acceptor was designed and synthesized, which exhibited excellent TADF property and strong intramolecular charge transfer. Meanwhile, the TPA-PQ can not only self-assemble to form nanofiber structure in mixed solvent of HO and THF, but also can be used as a type I photosensitizer to selectively produce superoxide anion radicals (O). More interestingly, the ROS generated from TPA-PQ can be used as photocatalysts for the oxidative hydroxylation of arylboronic acids and aerobic cross dehydrogenation coupling (CDC) reactions with high yields of 92 % and 88 %, respectively. This study presents an innovative and eco-friendly approach to utilize TADF supramolecular structures for the purpose of conducting photocatalyzed organic reactions.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"12 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1016/j.mtchem.2024.102247
Peng Liu, Yu Wu, Murugan Pachaiyappan, Run Zhou, Ling-Jun Yang, Zhi-Yong Qiu, Yu-Long Peng, Zai-Fang Li, Shi-Yong Liu
Although numerous photoactive layer materials have been explored for organic solar cells (OSCs), the cathode interface layer (CIL) materials still largely lag behind, however. Till now, ionic perylene diimide (PDI) derivatives are one of the most representative conjugated small molecules CIL materials for OSC. In this study, three new non-ionic star-shaped oligomeric CIL materials named , and involving 1,3,5-tribromo-2,4,6-trifluoro-benzene building, cyclopentadithiophene, rhodamine and 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile blocks were designed and facilely synthesized atom-economic direct C–H arylation for OSC. In the follow-up study of structure-property correlation, it was found that all three molecules possess the deepened work function (WF). show good electron transport, and are introduced into the PM6:Y6 system to further explore its effect as CIL that, can effectively suppress charge recombination. Among them, has the best effect of reducing the WF, which reduces the WF of the Ag electrode from 4.30 eV to 3.41 eV. Owing to its deepest WF and best alcoholic processability. The -based devices achieve a highest-power conversion efficiency (PCE) of 14.53 %, corresponding to a of 0.85 V, a of 25.17 mA cm, and an FF of 67.21 %. Our work opens up a new direction for non-ionic, non-PDI and non-fused ring star-shaped CIL materials, and thus diversify the CIL materials.
{"title":"Direct arylation-derived non-ionic star-shaped oligomeric CIL materials with Dramatically reduced work functions for organic solar cells","authors":"Peng Liu, Yu Wu, Murugan Pachaiyappan, Run Zhou, Ling-Jun Yang, Zhi-Yong Qiu, Yu-Long Peng, Zai-Fang Li, Shi-Yong Liu","doi":"10.1016/j.mtchem.2024.102247","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102247","url":null,"abstract":"Although numerous photoactive layer materials have been explored for organic solar cells (OSCs), the cathode interface layer (CIL) materials still largely lag behind, however. Till now, ionic perylene diimide (PDI) derivatives are one of the most representative conjugated small molecules CIL materials for OSC. In this study, three new non-ionic star-shaped oligomeric CIL materials named , and involving 1,3,5-tribromo-2,4,6-trifluoro-benzene building, cyclopentadithiophene, rhodamine and 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile blocks were designed and facilely synthesized atom-economic direct C–H arylation for OSC. In the follow-up study of structure-property correlation, it was found that all three molecules possess the deepened work function (WF). show good electron transport, and are introduced into the PM6:Y6 system to further explore its effect as CIL that, can effectively suppress charge recombination. Among them, has the best effect of reducing the WF, which reduces the WF of the Ag electrode from 4.30 eV to 3.41 eV. Owing to its deepest WF and best alcoholic processability. The -based devices achieve a highest-power conversion efficiency (PCE) of 14.53 %, corresponding to a of 0.85 V, a of 25.17 mA cm, and an FF of 67.21 %. Our work opens up a new direction for non-ionic, non-PDI and non-fused ring star-shaped CIL materials, and thus diversify the CIL materials.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"51 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-10DOI: 10.1016/j.mtchem.2024.102241
Yang Liu, Xulin Liu, Yongqi Tian, Run Ran, Chuang Du, Yawen Wang, Nana Ma, Ruinan Li, Xin Chai, Xueling Dong, Haikui Zou
Thermoresponsive aggregation-induced emission (AIE) luminogens, especially in the solid state, have attracted extensive attention due to their potential applications as smart materials. Herein, we report an AIE-active tetraphenylethene (TPE)-based Schiff base derivative (TPENOMe-I) that exhibits rapid and reversible thermochromism along with luminescence in the solid state. The excited-state intramolecular proton transfer-induced AIE and efficient thermochromism (rather than photochromism) are facilitated by the relatively compact crystal packing and polymorphism of TPENOMe-I, which effectively suppress -to- isomerization. Theoretical calculations demonstrated that the two-step isomerization process between the enol isomer and the - and twisted -keto isomers is responsible for the thermochromic behavior of solid-state TPENOMe-I. The chromic transitions may result from the reversible interconversion between various twisted -keto forms during the thermal isomerization process. Three composites containing TPENOMe-I that were simply prepared with low cost excited reversible thermochromism and were successfully demonstrated in thermochromic patterns. The findings suggest that these TPENOMe-I composites have promising applications for use in warning labels, thermochromic textiles, and thermal printing.
{"title":"An AIE-active Schiff base derivative with reversible thermochromism based on two-step isomerization in the solid state","authors":"Yang Liu, Xulin Liu, Yongqi Tian, Run Ran, Chuang Du, Yawen Wang, Nana Ma, Ruinan Li, Xin Chai, Xueling Dong, Haikui Zou","doi":"10.1016/j.mtchem.2024.102241","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102241","url":null,"abstract":"Thermoresponsive aggregation-induced emission (AIE) luminogens, especially in the solid state, have attracted extensive attention due to their potential applications as smart materials. Herein, we report an AIE-active tetraphenylethene (TPE)-based Schiff base derivative (TPENOMe-I) that exhibits rapid and reversible thermochromism along with luminescence in the solid state. The excited-state intramolecular proton transfer-induced AIE and efficient thermochromism (rather than photochromism) are facilitated by the relatively compact crystal packing and polymorphism of TPENOMe-I, which effectively suppress -to- isomerization. Theoretical calculations demonstrated that the two-step isomerization process between the enol isomer and the - and twisted -keto isomers is responsible for the thermochromic behavior of solid-state TPENOMe-I. The chromic transitions may result from the reversible interconversion between various twisted -keto forms during the thermal isomerization process. Three composites containing TPENOMe-I that were simply prepared with low cost excited reversible thermochromism and were successfully demonstrated in thermochromic patterns. The findings suggest that these TPENOMe-I composites have promising applications for use in warning labels, thermochromic textiles, and thermal printing.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"61 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-10DOI: 10.1016/j.mtchem.2024.102238
Priyanka Sharma, Abdurrahman Bilican, Wolfgang Schmidt, Cristina Ochoa-Hernández, Martin Etter, Claudia Weidenthaler
Nitrogen-doped carbon xerogels (CXNs) were carbonized across a range of temperatures (400 °C–800 °C) using sol-gel derived resorcinol-formaldehyde xerogel to elucidate their structural evolution during carbonization in ammonia. The investigation extensively probed chemical and structural changes in CXNs at varying carbonization temperatures, employing analytical methods such as X-ray photoelectron spectroscopy, infrared spectroscopy, and energy-dispersive X-ray spectroscopy. These findings were thoroughly compared with the local structure derived from total X-ray scattering and Raman spectroscopy. The results showed a transformation in the local ordering and chemical structure of CXNs, characterized by a reduction in oxidation sites, expansion of C sp network structures, leading to the growth of aromatic domains, and the incorporation of nitrogen into the carbon backbone structure. Pyrolysis in ammonia notably influenced the textural structure, resulting in a partial loss of mesopores and an increased micropore volume.
利用溶胶-凝胶衍生的间苯二酚-甲醛 xerogel 对掺氮碳 xerogel（CXNs）进行了不同温度（400 ℃-800 ℃）的碳化，以阐明其在氨中碳化过程中的结构演变。这项研究采用 X 射线光电子能谱、红外光谱和能量色散 X 射线光谱等分析方法，广泛探究了不同碳化温度下 CXNs 的化学和结构变化。这些发现与全 X 射线散射和拉曼光谱得出的局部结构进行了深入比较。结果表明，CXNs 的局部有序性和化学结构发生了变化，其特点是氧化位点减少、C sp 网络结构扩大，从而导致芳香结构域的增长，以及氮被纳入碳骨架结构。在氨气中的热解显著影响了纹理结构，导致中孔部分消失，微孔体积增大。
{"title":"Nitrogen doping in carbon xerogels via ammonia pyrolysis: A case study","authors":"Priyanka Sharma, Abdurrahman Bilican, Wolfgang Schmidt, Cristina Ochoa-Hernández, Martin Etter, Claudia Weidenthaler","doi":"10.1016/j.mtchem.2024.102238","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102238","url":null,"abstract":"Nitrogen-doped carbon xerogels (CXNs) were carbonized across a range of temperatures (400 °C–800 °C) using sol-gel derived resorcinol-formaldehyde xerogel to elucidate their structural evolution during carbonization in ammonia. The investigation extensively probed chemical and structural changes in CXNs at varying carbonization temperatures, employing analytical methods such as X-ray photoelectron spectroscopy, infrared spectroscopy, and energy-dispersive X-ray spectroscopy. These findings were thoroughly compared with the local structure derived from total X-ray scattering and Raman spectroscopy. The results showed a transformation in the local ordering and chemical structure of CXNs, characterized by a reduction in oxidation sites, expansion of C sp network structures, leading to the growth of aromatic domains, and the incorporation of nitrogen into the carbon backbone structure. Pyrolysis in ammonia notably influenced the textural structure, resulting in a partial loss of mesopores and an increased micropore volume.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"14 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-07DOI: 10.1016/j.mtchem.2024.102239
J. Wang, Y. Niu, Y. Yang, H. Peng, J. Zhang, C. Yao
Although the design strategies for thermally activated delayed fluorescence (TADF) molecules have gradually become richer and more refined, challenges still exist in the design of such materials. Typically, the highly twisted donor (D)-acceptor (A)-type structure of TADF materials presents a challenging contradiction between the desire for a minimal singlet-triplet energy gap (Δ) and the pursuit of high oscillator strength/photoluminescence quantum yield (). This study proposes an effective TADF molecular design strategy, which involves selecting a highly rigidity and planarity indolocarbazole (ICz) donor and a molecularly locked acceptor to construct molecules with a D-A-D configuration, successfully creating successfully creating emitters with high and a small Δ. These molecules exhibit strong TADF and aggregation-induced emission (AIE) characteristics in nondoped films, with exceeding 70.0 % and small Δ, small nonradiative transition rate constant, and larger reverse intersystem crossing constant (). Acting as excellent emitters in OLEDs, they provide efficient electroluminescence with CIE=(0.148, 0.119) for 23bCzSOB and CIE=(0.219, 0.463) for 23bCzTPO, with the highest current efficiency (CE) and external quantum efficiency (EQE) reaching 29.5 cd/A and 14.9 % for 23bCzSOB and 36.9 cd/A and 21.6 % for 23bCzTPO, respectively. These results indicate that the molecular design of efficient delayed fluorescence molecules is successful and promising.
{"title":"Towards efficient blue aggregation-induced emission and delayed fluorescence molecules by locking the skeleton of indolocarbazole derivatives for non-doped OLEDs","authors":"J. Wang, Y. Niu, Y. Yang, H. Peng, J. Zhang, C. Yao","doi":"10.1016/j.mtchem.2024.102239","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102239","url":null,"abstract":"Although the design strategies for thermally activated delayed fluorescence (TADF) molecules have gradually become richer and more refined, challenges still exist in the design of such materials. Typically, the highly twisted donor (D)-acceptor (A)-type structure of TADF materials presents a challenging contradiction between the desire for a minimal singlet-triplet energy gap (Δ) and the pursuit of high oscillator strength/photoluminescence quantum yield (). This study proposes an effective TADF molecular design strategy, which involves selecting a highly rigidity and planarity indolocarbazole (ICz) donor and a molecularly locked acceptor to construct molecules with a D-A-D configuration, successfully creating successfully creating emitters with high and a small Δ. These molecules exhibit strong TADF and aggregation-induced emission (AIE) characteristics in nondoped films, with exceeding 70.0 % and small Δ, small nonradiative transition rate constant, and larger reverse intersystem crossing constant (). Acting as excellent emitters in OLEDs, they provide efficient electroluminescence with CIE=(0.148, 0.119) for 23bCzSOB and CIE=(0.219, 0.463) for 23bCzTPO, with the highest current efficiency (CE) and external quantum efficiency (EQE) reaching 29.5 cd/A and 14.9 % for 23bCzSOB and 36.9 cd/A and 21.6 % for 23bCzTPO, respectively. These results indicate that the molecular design of efficient delayed fluorescence molecules is successful and promising.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"41 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141939650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Synchrotron radiation monochromatic X-ray computed tomography (CT) is a powerful tool for in-situ characterization of the internal microstructure evolution in composite materials. However, prolonged X-ray irradiation during long-term in-situ studies may affect the structure and properties of material. While the effects of white beam irradiation have been widely investigated, the specific damage mechanisms and material sensitivity to monochromatic X-ray irradiation, particularly in composite materials like propellants, are not well understood. In this study, we identify the threshold irradiation time that triggers radiation damage in PBT propellant and observe the accumulation and worsening of damage over time, primarilyinitiated by ether bond cleavage, leading to radiation-induced decomposition and increased internal porosity. This resulted in a significant reduction in the mechanical strength of PBT propellant, particularly under prolonged exposure to synchrotron radiation. In contrast, the inert binder system HTPB propellant exhibited better radiation stability. Our study highlights the importance of considering both radiation-induced damage and material X-ray sensitivity when designing in-situ synchrotron radiation CT experiments for composite materials, and suggests that the development of dynamic experimental methods to further reduce the risk of radiation damage for high-reliability in-situ assessment of material properties, as well as the need for careful consideration of radiation effects in the design and safety evaluation of solid propellant systems working in extreme circumstance.
同步辐射单色 X 射线计算机断层扫描（CT）是现场表征复合材料内部微观结构演变的有力工具。然而，在长期原位研究过程中，长时间的 X 射线辐照可能会影响材料的结构和性能。虽然白光束辐照的影响已得到广泛研究，但具体的损伤机制和材料对单色 X 射线辐照的敏感性，尤其是对推进剂等复合材料的敏感性，还不十分清楚。在这项研究中，我们确定了引发 PBT 推进剂辐射损伤的阈值辐照时间，并观察到随着时间的推移，主要由醚键裂解引发的损伤累积和恶化，从而导致辐射诱导的分解和内部孔隙率增加。这导致 PBT 推进剂的机械强度大大降低，尤其是在长期暴露于同步辐射的情况下。相比之下，惰性粘合剂系统 HTPB 推进剂则表现出更好的辐射稳定性。我们的研究强调了在设计复合材料原位同步辐射 CT 实验时同时考虑辐射诱导损伤和材料 X 射线敏感性的重要性，并建议开发动态实验方法以进一步降低辐射损伤风险，从而实现高可靠性的材料性能原位评估，以及在极端环境下工作的固体推进剂系统的设计和安全评估中仔细考虑辐射效应的必要性。
{"title":"In-situ investigation of damage evolution and mechanism in composite propellants under monochromatic X-ray irradiation","authors":"Tianhao Wang, Xiuyan Zhang, Haolin Luo, Chengli Mao, Jiaxing Wang, Weichen Sheng, Kuai He, Zhi Jiang","doi":"10.1016/j.mtchem.2024.102237","DOIUrl":"https://doi.org/10.1016/j.mtchem.2024.102237","url":null,"abstract":"Synchrotron radiation monochromatic X-ray computed tomography (CT) is a powerful tool for in-situ characterization of the internal microstructure evolution in composite materials. However, prolonged X-ray irradiation during long-term in-situ studies may affect the structure and properties of material. While the effects of white beam irradiation have been widely investigated, the specific damage mechanisms and material sensitivity to monochromatic X-ray irradiation, particularly in composite materials like propellants, are not well understood. In this study, we identify the threshold irradiation time that triggers radiation damage in PBT propellant and observe the accumulation and worsening of damage over time, primarilyinitiated by ether bond cleavage, leading to radiation-induced decomposition and increased internal porosity. This resulted in a significant reduction in the mechanical strength of PBT propellant, particularly under prolonged exposure to synchrotron radiation. In contrast, the inert binder system HTPB propellant exhibited better radiation stability. Our study highlights the importance of considering both radiation-induced damage and material X-ray sensitivity when designing in-situ synchrotron radiation CT experiments for composite materials, and suggests that the development of dynamic experimental methods to further reduce the risk of radiation damage for high-reliability in-situ assessment of material properties, as well as the need for careful consideration of radiation effects in the design and safety evaluation of solid propellant systems working in extreme circumstance.","PeriodicalId":18353,"journal":{"name":"Materials Today Chemistry","volume":"12 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141939651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：