Jan Bruder, Karen Fischer, Jonas Armleder, Erich Müller, Nicola Da Roit, Silke Behrens, Yuman Peng, Wolfgang Wenzel, Holger Röhm, Alexander Colsmann
Hydrogen generation in electrostatically stabilized, aqueous organic nanoparticle dispersions is investigated. For this purpose, organic nanoparticle dispersions are synthesized in water by nanoprecipitation from tetrahydrofuran and stabilized by charging through strong molecular electron acceptors. The dispersions are stable for more than 10 weeks on the shelf and during the photocatalytic process, despite the continuous transfer of charges between the reactants. The hydrogen generation in the electrostatically stabilized dispersions outperforms the hydrogen generation in organic nanoparticle dispersions which contain the common stabilizer sodium dodecyl sulfate.
{"title":"Photocatalytic Hydrogen Generation in Surfactant-Free, Aqueous Organic Nanoparticle Dispersions.","authors":"Jan Bruder, Karen Fischer, Jonas Armleder, Erich Müller, Nicola Da Roit, Silke Behrens, Yuman Peng, Wolfgang Wenzel, Holger Röhm, Alexander Colsmann","doi":"10.1002/smll.202406236","DOIUrl":"https://doi.org/10.1002/smll.202406236","url":null,"abstract":"<p><p>Hydrogen generation in electrostatically stabilized, aqueous organic nanoparticle dispersions is investigated. For this purpose, organic nanoparticle dispersions are synthesized in water by nanoprecipitation from tetrahydrofuran and stabilized by charging through strong molecular electron acceptors. The dispersions are stable for more than 10 weeks on the shelf and during the photocatalytic process, despite the continuous transfer of charges between the reactants. The hydrogen generation in the electrostatically stabilized dispersions outperforms the hydrogen generation in organic nanoparticle dispersions which contain the common stabilizer sodium dodecyl sulfate.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cancer immunotherapy offers significant clinical benefits for patients with advanced or metastatic tumors. However, immunotherapeutic efficacy is often hindered by the tumor microenvironment's high redox levels, leading to variable patient outcomes. Herein, a therapeutic liposomal gold nanocage (MGL) is innovatively developed based on photo-triggered hyperthermia and a releasable strategy by combining a glutathione (GSH) depletion to remodel the tumor immune microenvironment, fostering a more robust anti-tumor immune response. MGL comprises a thermosensitive liposome shell and a gold nanocage core loaded with maleimide. The flexible shell promotes efficient uptake by cancer cells, enabling targeted destruction through photothermal therapy while triggering immunogenic cell death and the maturation of antigen-presenting cells. The photoactivated release of maleimide depletes intracellular GSH, increasing tumor cell sensitivity to oxidative stress and thermal damage. Conversely, GSH reduction also diminishes immunosuppressive cell activity, enhances antigen presentation, and activates T cells. Moreover, photothermal immunotherapy decreases elevated levels of heat shock proteins in tumor cells, further increasing their sensitivity to hyperthermia. In summary, MGL elicited a robust systemic antitumor immune response through GSH depletion, facilitating an effective photothermal immunotherapeutic strategy that reprograms the tumor microenvironment and significantly inhibits primary and metastatic tumors. This approach demonstrates considerable translational potential and clinical applicability.
癌症免疫疗法可为晚期或转移性肿瘤患者带来显著的临床疗效。然而,免疫疗法的疗效往往受到肿瘤微环境高氧化还原水平的阻碍,导致患者疗效不一。本文创新性地开发了一种治疗性脂质体金纳米笼(MGL),它基于光触发热疗和可释放策略,通过结合谷胱甘肽(GSH)消耗来重塑肿瘤免疫微环境,从而促进更强大的抗肿瘤免疫反应。MGL 由热敏脂质体外壳和负载马来酰亚胺的金纳米笼核心组成。柔性外壳可促进癌细胞的有效吸收,从而通过光热疗法进行靶向破坏,同时引发免疫性细胞死亡和抗原递呈细胞的成熟。马来酰亚胺的光活化释放会消耗细胞内的 GSH,增加肿瘤细胞对氧化应激和热损伤的敏感性。相反,GSH 的减少也会降低免疫抑制细胞的活性,增强抗原递呈,激活 T 细胞。此外,光热免疫疗法还能降低肿瘤细胞中升高的热休克蛋白水平,进一步提高它们对热疗的敏感性。总之,MGL 通过消耗 GSH 引起了强大的全身性抗肿瘤免疫反应,促进了有效的光热免疫治疗策略,重塑了肿瘤微环境,显著抑制了原发性和转移性肿瘤。这种方法具有相当大的转化潜力和临床适用性。
{"title":"Reprogramming the Tumor Immune Microenvironment Through Activatable Photothermal Therapy and GSH depletion Using Liposomal Gold Nanocages to Potentiate Anti-Metastatic Immunotherapy.","authors":"Jiayi Li, Kaifan Zheng, Luping Lin, Mengdi Zhang, Ziqi Zhang, Junyu Chen, Shaoguang Li, Hong Yao, Ailin Liu, Xinhua Lin, Gang Liu, Bing Chen","doi":"10.1002/smll.202407388","DOIUrl":"https://doi.org/10.1002/smll.202407388","url":null,"abstract":"<p><p>Cancer immunotherapy offers significant clinical benefits for patients with advanced or metastatic tumors. However, immunotherapeutic efficacy is often hindered by the tumor microenvironment's high redox levels, leading to variable patient outcomes. Herein, a therapeutic liposomal gold nanocage (MGL) is innovatively developed based on photo-triggered hyperthermia and a releasable strategy by combining a glutathione (GSH) depletion to remodel the tumor immune microenvironment, fostering a more robust anti-tumor immune response. MGL comprises a thermosensitive liposome shell and a gold nanocage core loaded with maleimide. The flexible shell promotes efficient uptake by cancer cells, enabling targeted destruction through photothermal therapy while triggering immunogenic cell death and the maturation of antigen-presenting cells. The photoactivated release of maleimide depletes intracellular GSH, increasing tumor cell sensitivity to oxidative stress and thermal damage. Conversely, GSH reduction also diminishes immunosuppressive cell activity, enhances antigen presentation, and activates T cells. Moreover, photothermal immunotherapy decreases elevated levels of heat shock proteins in tumor cells, further increasing their sensitivity to hyperthermia. In summary, MGL elicited a robust systemic antitumor immune response through GSH depletion, facilitating an effective photothermal immunotherapeutic strategy that reprograms the tumor microenvironment and significantly inhibits primary and metastatic tumors. This approach demonstrates considerable translational potential and clinical applicability.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xingmiao Yu, Jianfei Xiang, Qitao Shi, Luwen Li, Jiaqi Wang, Xiangqi Liu, Cheng Zhang, Zhipeng Wang, Junjin Zhang, Huimin Hu, Alicja Bachmatiuk, Barbara Trzebicka, Jin Chen, Tianxiao Guo, Yanbin Shen, Jinho Choi, Cheng Huang, Mark H Rümmeli
Graphitic carbon materials are widely used in lithium-ion batteries (LIBs) due to their stability and high conductivity. However, graphite anodes have low specific capacity and degrade over time, limiting their application. To meet advanced energy storage needs, high-performance graphitic carbon materials are required. Enhancing the electrochemical performance of carbon materials can be achieved through boron and nitrogen doping and incorporating 3D structures such as carbon nanocages (CNCs). In this study, aluminum (Al) is introduced into CNC lattices via chemical vapor deposition (CVD). The hollow structure of CNCs enables fast electrolyte penetration. Density functional theory (DFT) calculations show that Al doping lowers the intercalation energy of Li+. The Al-boron (B)-nitrogen (N-doped CNC (AlBN-CNC) anode demonstrates an ultrahigh rate capacity (≈300 mAh g-1 at 10 A g-1) and a prolonged fast-charging lifespan (862.82 mAh g-1 at 5 A g-1 after 1000 cycles), surpassing the N-doped or BN-doped CNCs. Al doping improves charging kinetics and structural stability. Surprisingly, AlBN-CNCs exhibit increased capacity upon cycling due to enlarged graphitic interlayer spacing. Characterization of graphitic nanostructures confirms that Al doping effectively tailors and enhances their electrochemical properties, providing a new strategy for high-capacity, fast-charging graphitic carbon anode materials for next-generation LIBs.
石墨碳材料因其稳定性和高导电性而被广泛应用于锂离子电池(LIB)中。然而,石墨阳极的比容量较低,并且会随着时间的推移而降解,从而限制了其应用。为了满足先进的储能需求,需要高性能的石墨碳材料。通过掺杂硼和氮以及加入碳纳米笼(CNC)等三维结构,可以提高碳材料的电化学性能。本研究通过化学气相沉积(CVD)将铝(Al)引入 CNC 晶格。CNC 的中空结构使电解质能够快速渗透。密度泛函理论 (DFT) 计算表明,铝掺杂降低了 Li+ 的闰化能。掺杂铝-硼(B)-氮(N)的 CNC(AlBN-CNC)阳极具有超高的速率容量(10 A g-1 时≈300 mAh g-1)和超长的快速充电寿命(1000 次循环后,5 A g-1 时为 862.82 mAh g-1),超过了掺杂 N 或 BN 的 CNC。铝掺杂提高了充电动力学和结构稳定性。令人惊讶的是,AlBN-CNC 在循环过程中由于扩大了石墨层间距而显示出更高的容量。对石墨纳米结构的表征证实,铝掺杂能有效地调整和增强其电化学特性,为下一代 LIB 的高容量、快速充电石墨碳负极材料提供了一种新策略。
{"title":"Tailoring the Li<sup>+</sup> Intercalation Energy of Carbon Nanocage Anodes Via Atomic Al-Doping for High-Performance Lithium-Ion Batteries.","authors":"Xingmiao Yu, Jianfei Xiang, Qitao Shi, Luwen Li, Jiaqi Wang, Xiangqi Liu, Cheng Zhang, Zhipeng Wang, Junjin Zhang, Huimin Hu, Alicja Bachmatiuk, Barbara Trzebicka, Jin Chen, Tianxiao Guo, Yanbin Shen, Jinho Choi, Cheng Huang, Mark H Rümmeli","doi":"10.1002/smll.202406309","DOIUrl":"https://doi.org/10.1002/smll.202406309","url":null,"abstract":"<p><p>Graphitic carbon materials are widely used in lithium-ion batteries (LIBs) due to their stability and high conductivity. However, graphite anodes have low specific capacity and degrade over time, limiting their application. To meet advanced energy storage needs, high-performance graphitic carbon materials are required. Enhancing the electrochemical performance of carbon materials can be achieved through boron and nitrogen doping and incorporating 3D structures such as carbon nanocages (CNCs). In this study, aluminum (Al) is introduced into CNC lattices via chemical vapor deposition (CVD). The hollow structure of CNCs enables fast electrolyte penetration. Density functional theory (DFT) calculations show that Al doping lowers the intercalation energy of Li<sup>+</sup>. The Al-boron (B)-nitrogen (N-doped CNC (AlBN-CNC) anode demonstrates an ultrahigh rate capacity (≈300 mAh g<sup>-1</sup> at 10 A g<sup>-1</sup>) and a prolonged fast-charging lifespan (862.82 mAh g<sup>-1</sup> at 5 A g<sup>-1</sup> after 1000 cycles), surpassing the N-doped or BN-doped CNCs. Al doping improves charging kinetics and structural stability. Surprisingly, AlBN-CNCs exhibit increased capacity upon cycling due to enlarged graphitic interlayer spacing. Characterization of graphitic nanostructures confirms that Al doping effectively tailors and enhances their electrochemical properties, providing a new strategy for high-capacity, fast-charging graphitic carbon anode materials for next-generation LIBs.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lei Wang, Letu SiQin, Yiming Wang, Shuyu Li, Wenjing Xin, Jingyuan Guo, Ruijian Liu, Hongmei Luan, Chengjun Zhu
The Sol-gel precursor solution reaction mechanism has a significant impact on the Cu2ZnSn(S, Se)4 (CZTSSe) solar cells. It is discovered that in the Cu2ZnSnS4 (CZTS) precursor solution (CZTS-PS) in the preparation, there is an association reaction among Cu2+, thiourea (Tu), and carboxyl (-COOH), which is an important reason for the undesirable CZTSSe solar cells. The strong association reaction generates excessive Cu2+ ions, forming the CuxSe secondary phase on the surface of the CZTSSe absorber. The secondary phase causes a short circuit and deterioration of gadget performance. Following a 6-h aging period for the CZTS-PS, the average photoelectric conversion efficiency (PCE) of the device is enhanced to 8.02%, and there is also an improvement in device uniformity, as evidenced by a decrease in the standard deviation to less than 1. To inhibit the association reaction and eliminate the aging time phenomenon, a strategy is developed using hydrochloric acid to regulate the CZTS-PS environment. This strategy shifts the REDOX reaction in Cu2++Sn2+ toward the formation of Cu1++Sn4+, leading to a decrease in the defect concentrations of VSn(-/0) and CuSn(-/0), which increases the carrier concentration and reduces the impact of band tailing. The average power conversion efficiency (PCE) of the devices improved from 7.45% to 9.26%, the PCE of the best-performing CZTSSe solar cells increased from 9.25% to 9.83%, and the consistency among the devices is further enhanced, as indicated by a reduction in the standard deviation from 0.98 to 0.44. Ultimately, the device performance of the Cu2++Sn2+-DMF system improved by 11.01% (without the MgF2 layer) after optimization. This study serves as a reference for regulating the environment of the CZTS-PS to further enhance the CZTSSe devices' performance, and the photoelectric conversion efficiency is improved by ≈30%.
{"title":"Enhance the Performance of CZTSSe Solar Cells Through Inhibiting the Cu<sup>2+</sup>, Tu, and (─COOH) Association Reaction.","authors":"Lei Wang, Letu SiQin, Yiming Wang, Shuyu Li, Wenjing Xin, Jingyuan Guo, Ruijian Liu, Hongmei Luan, Chengjun Zhu","doi":"10.1002/smll.202405908","DOIUrl":"https://doi.org/10.1002/smll.202405908","url":null,"abstract":"<p><p>The Sol-gel precursor solution reaction mechanism has a significant impact on the Cu<sub>2</sub>ZnSn(S, Se)<sub>4</sub> (CZTSSe) solar cells. It is discovered that in the Cu<sub>2</sub>ZnSnS<sub>4</sub> (CZTS) precursor solution (CZTS-PS) in the preparation, there is an association reaction among Cu<sup>2+</sup>, thiourea (Tu), and carboxyl (-COOH), which is an important reason for the undesirable CZTSSe solar cells. The strong association reaction generates excessive Cu<sup>2+</sup> ions, forming the Cu<sub>x</sub>Se secondary phase on the surface of the CZTSSe absorber. The secondary phase causes a short circuit and deterioration of gadget performance. Following a 6-h aging period for the CZTS-PS, the average photoelectric conversion efficiency (PCE) of the device is enhanced to 8.02%, and there is also an improvement in device uniformity, as evidenced by a decrease in the standard deviation to less than 1. To inhibit the association reaction and eliminate the aging time phenomenon, a strategy is developed using hydrochloric acid to regulate the CZTS-PS environment. This strategy shifts the REDOX reaction in Cu<sup>2+</sup>+Sn<sup>2+</sup> toward the formation of Cu<sup>1+</sup>+Sn<sup>4+</sup>, leading to a decrease in the defect concentrations of V<sub>Sn</sub>(-/0) and Cu<sub>Sn</sub>(-/0), which increases the carrier concentration and reduces the impact of band tailing. The average power conversion efficiency (PCE) of the devices improved from 7.45% to 9.26%, the PCE of the best-performing CZTSSe solar cells increased from 9.25% to 9.83%, and the consistency among the devices is further enhanced, as indicated by a reduction in the standard deviation from 0.98 to 0.44. Ultimately, the device performance of the Cu<sup>2+</sup>+Sn<sup>2+</sup>-DMF system improved by 11.01% (without the MgF<sub>2</sub> layer) after optimization. This study serves as a reference for regulating the environment of the CZTS-PS to further enhance the CZTSSe devices' performance, and the photoelectric conversion efficiency is improved by ≈30%.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Araz Rajabi-Abhari, Hyunjoon Yoo, Ji-Seok Kim, Hong Yeon Yoon, Jeong Young Park, Ning Yan, Rassoul Tabassian, Il-Kwon Oh
The integration of bio-based materials into triboelectric nanogenerators (TENGs) for energy harvesting from human body motions has sparked considerable research attention. Here, a silanated cellulose nanofibril (SCNF) aerogel is reported for structurally reliable TENGs and reversely compressible Taekwondo scoring sensors under repeated impacts. The preparation of the aerogel involves silanizing cellulose nanofibers (CNFs) with vinyltrimethoxysilane (VTMS), following by freeze-drying and post-heating treatment. The SCNF aerogel with crosslinked physico-chemical bonding and highly porous network is found to exhibit superior mechanical strength and reversible compressibility as well as enhanced water repellency and electron-donating ability. The TENG having a tribo-positive SCNF layer exhibits exceptional triboelectric performances, generating a voltage of 270 V, current of 11 µA, and power density of 401.1 mW m-2 under an applied force of 8 N at a frequency of 5 Hz. With its inherent merits in material composition, structural configuration, and device sensitivity, the SCNF TENG demonstrates the capability to seamlessly integrate into a Taekwondo protection gear, serving as an efficient self-powered sensor for monitoring hitting scores. This study highlights the significant potential of a facilely fabricated SCNF aerogel for the development of high-performance, bio-friendly, and cost-effective Bio-TENGs, enabling their application as self-powered wearable devices and sports engineering sensors.
将生物基材料集成到三电纳米发电机(TENGs)中以从人体运动中获取能量的研究引起了广泛关注。本文报告了一种硅烷化纤维素纳米纤维(SCNF)气凝胶,可用于结构可靠的 TENG 和反复冲击下可反向压缩的跆拳道得分传感器。气凝胶的制备过程包括用乙烯基三甲氧基硅烷(VTMS)对纤维素纳米纤维(CNF)进行硅烷化,然后进行冷冻干燥和后加热处理。结果发现,具有交联物理化学结合和高多孔性网络的 SCNF 气凝胶具有优异的机械强度和可逆压缩性,并增强了憎水性和电子负载能力。具有三正极 SCNF 层的 TENG 表现出卓越的三电性能,在频率为 5 Hz、外力为 8 N 的情况下,可产生 270 V 的电压、11 µA 的电流和 401.1 mW m-2 的功率密度。SCNF TENG 在材料组成、结构配置和器件灵敏度方面具有固有的优点,能够无缝集成到跆拳道保护装备中,成为监测击打得分的高效自供电传感器。这项研究凸显了易于制造的 SCNF 气凝胶在开发高性能、生物友好型和高性价比生物 TENG 方面的巨大潜力,使其能够应用于自供电可穿戴设备和运动工程传感器。
{"title":"Reversibly Compressible Silanated Cellulose Nanofibril Aerogel for Triboelectric Taekwondo Scoring Sensors.","authors":"Araz Rajabi-Abhari, Hyunjoon Yoo, Ji-Seok Kim, Hong Yeon Yoon, Jeong Young Park, Ning Yan, Rassoul Tabassian, Il-Kwon Oh","doi":"10.1002/smll.202405664","DOIUrl":"https://doi.org/10.1002/smll.202405664","url":null,"abstract":"<p><p>The integration of bio-based materials into triboelectric nanogenerators (TENGs) for energy harvesting from human body motions has sparked considerable research attention. Here, a silanated cellulose nanofibril (SCNF) aerogel is reported for structurally reliable TENGs and reversely compressible Taekwondo scoring sensors under repeated impacts. The preparation of the aerogel involves silanizing cellulose nanofibers (CNFs) with vinyltrimethoxysilane (VTMS), following by freeze-drying and post-heating treatment. The SCNF aerogel with crosslinked physico-chemical bonding and highly porous network is found to exhibit superior mechanical strength and reversible compressibility as well as enhanced water repellency and electron-donating ability. The TENG having a tribo-positive SCNF layer exhibits exceptional triboelectric performances, generating a voltage of 270 V, current of 11 µA, and power density of 401.1 mW m<sup>-2</sup> under an applied force of 8 N at a frequency of 5 Hz. With its inherent merits in material composition, structural configuration, and device sensitivity, the SCNF TENG demonstrates the capability to seamlessly integrate into a Taekwondo protection gear, serving as an efficient self-powered sensor for monitoring hitting scores. This study highlights the significant potential of a facilely fabricated SCNF aerogel for the development of high-performance, bio-friendly, and cost-effective Bio-TENGs, enabling their application as self-powered wearable devices and sports engineering sensors.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Boyan Zhang, Peiyu Ma, Ruyang Wang, Heng Cao, Jun Bao
Designing efficient and durable electrocatalysts for oxygen reduction reaction (ORR) is essential for proton exchange membrane fuel cells (PEMFCs). Platinum-based catalysts are considered efficient ORR catalysts due to their high activity. However, the degradation of Pt species leads to poor durability of catalysts, limiting their applications in PEMFCs. Herein, a Janus heterostructure is designed for high durability ORR in acidic media. The Janus heterostructure composes of crystalline platinum and cassiterite tin oxide nanoparticles with carbon support (J-Pt@SnO2/C). Based on the synchrotron fine structure analysis and electrochemical investigation, the crystalline reconstruction and charge redistribution at the interface of Janus structure are revealed. The tightly coupled interface could optimize the valance states of Pt and the adsorption/desorption of oxygenated intermediates. As a result, the J-Pt@SnO2/C catalyst possesses distinguishing long-term stability during the accelerated durability test without obvious degradation after 40 000 cycles and keeps the majority of activity after 70 000 cycles. Meanwhile, the catalyst exhibits outstanding activity with half-wave potential at 0.905 V and a mass activity of 0.355 A mgPt-1 (2.7 times higher than Pt/C). The approach of the Janus catalyst paves an avenue for designing highly efficient and stable Pt-based ORR catalyst in the future implementation.
{"title":"A Janus Platinum/Tin Oxide Heterostructure for Durable Oxygen Reduction Reaction.","authors":"Boyan Zhang, Peiyu Ma, Ruyang Wang, Heng Cao, Jun Bao","doi":"10.1002/smll.202405234","DOIUrl":"https://doi.org/10.1002/smll.202405234","url":null,"abstract":"<p><p>Designing efficient and durable electrocatalysts for oxygen reduction reaction (ORR) is essential for proton exchange membrane fuel cells (PEMFCs). Platinum-based catalysts are considered efficient ORR catalysts due to their high activity. However, the degradation of Pt species leads to poor durability of catalysts, limiting their applications in PEMFCs. Herein, a Janus heterostructure is designed for high durability ORR in acidic media. The Janus heterostructure composes of crystalline platinum and cassiterite tin oxide nanoparticles with carbon support (J-Pt@SnO<sub>2</sub>/C). Based on the synchrotron fine structure analysis and electrochemical investigation, the crystalline reconstruction and charge redistribution at the interface of Janus structure are revealed. The tightly coupled interface could optimize the valance states of Pt and the adsorption/desorption of oxygenated intermediates. As a result, the J-Pt@SnO<sub>2</sub>/C catalyst possesses distinguishing long-term stability during the accelerated durability test without obvious degradation after 40 000 cycles and keeps the majority of activity after 70 000 cycles. Meanwhile, the catalyst exhibits outstanding activity with half-wave potential at 0.905 V and a mass activity of 0.355 A mg<sub>Pt</sub> <sup>-1</sup> (2.7 times higher than Pt/C). The approach of the Janus catalyst paves an avenue for designing highly efficient and stable Pt-based ORR catalyst in the future implementation.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Conjugated microporous polymers (CMPs) are an important class of organic materials with several useful features like, inherent nanoscale porosity, large specific surface area and semiconducting properties, which are very demanding for various sustainable applications. Carbazole building blocks are extensively used in designing photocatalysts due to easy electron donation and hole transportation. In the current study, a new CMP material CBZ-CMP containing carbazole unit used for photocatalytic C═N coupling reaction under blue light irradiation is designed. The CBZ-CMP framework is made through the polycondensation of 4,4'-di(9H-carbazol-9-yl)-1,1'-biphenyl using FeCl3 as a catalyst. The CBZ-CMP shows very high BET surface area of 1536 m2 g-1 together with unimodal porosity (ca. 1.7 nm supermicropore), nanowire-like particle morphology (16-18 nm diameter), and low band gap property. The bi-phenyl moiety functions as the electron accepting center and the carbazole unit acts as the donor center, which accounts for the low band gap energy of CBZ-CMP. This nanoporous semiconducting CBZ-CMP material for photocatalytic benzylamine coupling reaction is explored, where it shows good conversion together with high selectivity under mild reaction conditions. This study offers simple method of preparation of a D-A-D-based porous photocatalyst for sustainable synthesis of value-added organics.
{"title":"Rational Design of Highly Porous Donor-Acceptor Based Conjugated Microporous Polymer for Photocatalytic Benzylamine Coupling Reaction.","authors":"Sudip Bhattacharjee, Sumanta Mondal, Anirban Ghosh, Soumadip Banerjee, Abhijit K Das, Asim Bhaumik","doi":"10.1002/smll.202406723","DOIUrl":"https://doi.org/10.1002/smll.202406723","url":null,"abstract":"<p><p>Conjugated microporous polymers (CMPs) are an important class of organic materials with several useful features like, inherent nanoscale porosity, large specific surface area and semiconducting properties, which are very demanding for various sustainable applications. Carbazole building blocks are extensively used in designing photocatalysts due to easy electron donation and hole transportation. In the current study, a new CMP material CBZ-CMP containing carbazole unit used for photocatalytic C═N coupling reaction under blue light irradiation is designed. The CBZ-CMP framework is made through the polycondensation of 4,4'-di(9H-carbazol-9-yl)-1,1'-biphenyl using FeCl<sub>3</sub> as a catalyst. The CBZ-CMP shows very high BET surface area of 1536 m<sup>2</sup> g<sup>-1</sup> together with unimodal porosity (ca. 1.7 nm supermicropore), nanowire-like particle morphology (16-18 nm diameter), and low band gap property. The bi-phenyl moiety functions as the electron accepting center and the carbazole unit acts as the donor center, which accounts for the low band gap energy of CBZ-CMP. This nanoporous semiconducting CBZ-CMP material for photocatalytic benzylamine coupling reaction is explored, where it shows good conversion together with high selectivity under mild reaction conditions. This study offers simple method of preparation of a D-A-D-based porous photocatalyst for sustainable synthesis of value-added organics.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-08-21DOI: 10.1002/smll.202404809
Jonathan Bradford, Benjamin T Dewes, Mustaqeem Shiffa, Nathan D Cottam, Kazi Rahman, Tin S Cheng, Sergei V Novikov, Oleg Makarovsky, James N O'Shea, Peter H Beton, Samuel Lara-Avila, Jordan Harknett, Mark T Greenaway, Amalia Patanè
2D semiconductors can drive advances in quantum science and technologies. However, they should be free of any contamination; also, the crystallographic ordering and coupling of adjacent layers and their electronic properties should be well-controlled, tunable, and scalable. Here, these challenges are addressed by a new approach, which combines molecular beam epitaxy and in situ band engineering in ultra-high vacuum of semiconducting gallium selenide (GaSe) on graphene. In situ studies by electron diffraction, scanning probe microscopy, and angle-resolved photoelectron spectroscopy reveal that atomically-thin layers of GaSe align in the layer plane with the underlying lattice of graphene. The GaSe/graphene heterostructure, referred to as 2semgraphene, features a centrosymmetric (group symmetry D3d) polymorph of GaSe, a charge dipole at the GaSe/graphene interface, and a band structure tunable by the layer thickness. The newly-developed, scalable 2semgraphene is used in optical sensors that exploit the photoactive GaSe layer and the built-in potential at its interface with the graphene channel. This proof of concept has the potential for further advances and device architectures that exploit 2semgraphene as a functional building block.
{"title":"Epitaxy of GaSe Coupled to Graphene: From In Situ Band Engineering to Photon Sensing.","authors":"Jonathan Bradford, Benjamin T Dewes, Mustaqeem Shiffa, Nathan D Cottam, Kazi Rahman, Tin S Cheng, Sergei V Novikov, Oleg Makarovsky, James N O'Shea, Peter H Beton, Samuel Lara-Avila, Jordan Harknett, Mark T Greenaway, Amalia Patanè","doi":"10.1002/smll.202404809","DOIUrl":"10.1002/smll.202404809","url":null,"abstract":"<p><p>2D semiconductors can drive advances in quantum science and technologies. However, they should be free of any contamination; also, the crystallographic ordering and coupling of adjacent layers and their electronic properties should be well-controlled, tunable, and scalable. Here, these challenges are addressed by a new approach, which combines molecular beam epitaxy and in situ band engineering in ultra-high vacuum of semiconducting gallium selenide (GaSe) on graphene. In situ studies by electron diffraction, scanning probe microscopy, and angle-resolved photoelectron spectroscopy reveal that atomically-thin layers of GaSe align in the layer plane with the underlying lattice of graphene. The GaSe/graphene heterostructure, referred to as 2semgraphene, features a centrosymmetric (group symmetry D<sub>3d</sub>) polymorph of GaSe, a charge dipole at the GaSe/graphene interface, and a band structure tunable by the layer thickness. The newly-developed, scalable 2semgraphene is used in optical sensors that exploit the photoactive GaSe layer and the built-in potential at its interface with the graphene channel. This proof of concept has the potential for further advances and device architectures that exploit 2semgraphene as a functional building block.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142015862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-05-30DOI: 10.1002/smll.202402661
Yang Jiang, Yutong Ming, Mohan Zhao, Xin Guo, Jiajia Han, Shijie Liu, Tao Jiang, Zhong Lin Wang
Traffic lights play vital roles in urban traffic management systems, providing clear directional guidance for vehicles and pedestrians while ensuring traffic safety. However, the vast quantity of traffic lights widely distributed in the transportation system aggravates energy consumption. Here, a self-powered traffic light system is proposed through wind energy harvesting based on a high-performance fur-brush dish triboelectric nanogenerator (FD-TENG). The FD-TENG harvests wind energy to power the traffic light system continuously without needing an external power supply. Natural rabbit furs are applied to dish structures, due to their outstanding characteristics of shallow wear, high performance, and resistance to humidity. Also, the grid pattern of the dish structure significantly impacts the TENG outputs. Additionally, the internal electric field and the influences of mechanical and structural parameters on the outputs are analyzed by finite element simulations. After optimization, the FD-TENG can achieve a peak power density of 3.275 W m-3. The portable and miniature features of FD-TENG make it suitable for other natural environment systems such as forests, oceans, and mountains, besides the traffic light systems. This study presents a viable strategy for self-powered traffic lights, establishing a basis for efficient environmental energy harvesting toward big data and Internet of Things applications.
交通信号灯在城市交通管理系统中发挥着重要作用,为车辆和行人提供清晰的方向指引,同时确保交通安全。然而,交通系统中广泛分布的大量交通灯加剧了能源消耗。在此,我们提出了一种基于高性能毛刷碟式三电纳米发电机(FD-TENG)的风能收集自供电交通灯系统。FD-TENG 可收集风能,为交通灯系统持续供电,无需外部电源。由于天然兔毛具有耐磨损、高性能和抗潮湿的突出特点,因此被应用于碟形结构。此外,碟形结构的栅格模式也会对 TENG 的输出产生重大影响。此外,还通过有限元模拟分析了内部电场以及机械和结构参数对输出的影响。经过优化,FD-TENG 的峰值功率密度可达 3.275 W m-3。FD-TENG 的便携性和微型化特点使其适用于交通灯系统之外的其他自然环境系统,如森林、海洋和山脉。这项研究提出了一种自供电交通灯的可行策略,为面向大数据和物联网应用的高效环境能源采集奠定了基础。
{"title":"Self-Powered Traffic Lights Through Wind Energy Harvesting Based on High-Performance Fur-Brush Dish Triboelectric Nanogenerators.","authors":"Yang Jiang, Yutong Ming, Mohan Zhao, Xin Guo, Jiajia Han, Shijie Liu, Tao Jiang, Zhong Lin Wang","doi":"10.1002/smll.202402661","DOIUrl":"10.1002/smll.202402661","url":null,"abstract":"<p><p>Traffic lights play vital roles in urban traffic management systems, providing clear directional guidance for vehicles and pedestrians while ensuring traffic safety. However, the vast quantity of traffic lights widely distributed in the transportation system aggravates energy consumption. Here, a self-powered traffic light system is proposed through wind energy harvesting based on a high-performance fur-brush dish triboelectric nanogenerator (FD-TENG). The FD-TENG harvests wind energy to power the traffic light system continuously without needing an external power supply. Natural rabbit furs are applied to dish structures, due to their outstanding characteristics of shallow wear, high performance, and resistance to humidity. Also, the grid pattern of the dish structure significantly impacts the TENG outputs. Additionally, the internal electric field and the influences of mechanical and structural parameters on the outputs are analyzed by finite element simulations. After optimization, the FD-TENG can achieve a peak power density of 3.275 W m<sup>-3</sup>. The portable and miniature features of FD-TENG make it suitable for other natural environment systems such as forests, oceans, and mountains, besides the traffic light systems. This study presents a viable strategy for self-powered traffic lights, establishing a basis for efficient environmental energy harvesting toward big data and Internet of Things applications.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141174070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-01Epub Date: 2024-06-03DOI: 10.1002/smll.202402344
Qiang Zou, Qi Liang, Henggang Zhou, Yongqiang Guo, Ji Xue, Mingkai Luo, Songyu Jia, Wenlong Liu, Sizhe Wang
Lithium-sulfur batteries (LSBs) are still limited by some issues such as polysulfides shuttle and lithium dendrites. Recently, the concept "high-entropy" has been considered as the research hotspot and international frontier. Herein, a high entropy MXene (TiVCrMoC3Tx, HE-MXene) doped graphene is designed as the modified coating on commercial separators for LSBs. The HE-MXene affords multiple metal active sites, fast Li+ diffusion rate, and efficient adsorption toward polysulfide intermediates. Furthermore, strong lithophilic property is favorable for uniform Li+ deposition. The combination of in situ characterizations confirms TiVCrMoC3Tx effectively promotes the Li2S nucleation/dissolution kinetics, reduces the Li+ diffusion barrier, and exhibits favorable lithium uniform deposition behavior. This TiVCrMoC3Tx/G@PP provides a high-capacity retention rate after 1000 cycles at 1 C and 2 C, with a capacity decay rate of merely 0.021% and 0.022% per cycle. Surprisingly, the cell operates at a low potential of 48 mV while maintaining at 5 mA cm-2/5 mAh cm-2 for 4000 h. Furthermore, it still maintains a high-capacity retention rate under a high sulfur loading of 4.8/6.4 mg cm-2 and a low E/S ratio of 8.6/7.5 µg mL-1. This work reveals a technical roadmap for simultaneously addressing the cathode and anode challenge, thus achieving potential commercially viable LSBs.
{"title":"Promoting Li<sub>2</sub>S Nucleation/Dissolution Kinetics via Multiple Active Sites over TiVCrMoC<sub>3</sub>T<sub>x</sub> Interface.","authors":"Qiang Zou, Qi Liang, Henggang Zhou, Yongqiang Guo, Ji Xue, Mingkai Luo, Songyu Jia, Wenlong Liu, Sizhe Wang","doi":"10.1002/smll.202402344","DOIUrl":"10.1002/smll.202402344","url":null,"abstract":"<p><p>Lithium-sulfur batteries (LSBs) are still limited by some issues such as polysulfides shuttle and lithium dendrites. Recently, the concept \"high-entropy\" has been considered as the research hotspot and international frontier. Herein, a high entropy MXene (TiVCrMoC<sub>3</sub>T<sub>x</sub>, HE-MXene) doped graphene is designed as the modified coating on commercial separators for LSBs. The HE-MXene affords multiple metal active sites, fast Li<sup>+</sup> diffusion rate, and efficient adsorption toward polysulfide intermediates. Furthermore, strong lithophilic property is favorable for uniform Li<sup>+</sup> deposition. The combination of in situ characterizations confirms TiVCrMoC<sub>3</sub>T<sub>x</sub> effectively promotes the Li<sub>2</sub>S nucleation/dissolution kinetics, reduces the Li<sup>+</sup> diffusion barrier, and exhibits favorable lithium uniform deposition behavior. This TiVCrMoC<sub>3</sub>T<sub>x</sub>/G@PP provides a high-capacity retention rate after 1000 cycles at 1 C and 2 C, with a capacity decay rate of merely 0.021% and 0.022% per cycle. Surprisingly, the cell operates at a low potential of 48 mV while maintaining at 5 mA cm<sup>-2</sup>/5 mAh cm<sup>-2</sup> for 4000 h. Furthermore, it still maintains a high-capacity retention rate under a high sulfur loading of 4.8/6.4 mg cm<sup>-2</sup> and a low E/S ratio of 8.6/7.5 µg mL<sup>-1</sup>. This work reveals a technical roadmap for simultaneously addressing the cathode and anode challenge, thus achieving potential commercially viable LSBs.</p>","PeriodicalId":228,"journal":{"name":"Small","volume":null,"pages":null},"PeriodicalIF":13.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141198672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}