Cong Zhang, Ze-Hui Wang, Haiyan Wang, Jin-Xia Liang, Chun Zhu, Jun Li
Single-cluster catalysts (SCCs) representing structurally well-defined metal clusters anchored on support tend to exhibit tuneable catalytic performance for complex redox reactions in heterogeneous catalysis. Here we report a theoretical study on an SCC of Ru3@Mo2CO2 MXene for N2-to-NH3 thermal conversion. Our results show that Ru3@Mo2CO2 can effectively activate N2 and promotes its conversion to NH3 through an association mechanism, in which the rate-determining step of NH2* + H* → NH3* has a low energy barrier of 1.29 eV. Especially, with the assistance of Mo2CO2 support, the positively charged Ru3 cluster active site can effectively adsorb and activate N2, leading to 0.74 |e| charge transfer from Ru3@Mo2CO2 to the adsorbed N2. The supported Ru3 also acts as an electron reservoir to regulate the charge transfer for various intermediate steps of ammonia synthesis. Microkinetic analysis shows that the turnover frequency (TOF) of the N2-to-NH3 conversion on Ru3@Mo2CO2 is as high as 1.45 × 10−2 s−1 site−1 at a selected thermodynamic condition of 48 bar and 700 K, the performance of which even surpasses those of the Ru B5 site and Fe3/θ-Al2O3(010) reported before. Our work provides a theoretical understanding on the high stability and catalytic mechanism of Ru3@Mo2CO2 and guidance for further designing and fabricating MXene-based metal SCCs for ammonia synthesis under mild conditions.
{"title":"Ru3@Mo2CO2 MXene single-cluster catalyst for highly efficient N2-to-NH3 conversion","authors":"Cong Zhang, Ze-Hui Wang, Haiyan Wang, Jin-Xia Liang, Chun Zhu, Jun Li","doi":"10.1093/nsr/nwae251","DOIUrl":"https://doi.org/10.1093/nsr/nwae251","url":null,"abstract":"Single-cluster catalysts (SCCs) representing structurally well-defined metal clusters anchored on support tend to exhibit tuneable catalytic performance for complex redox reactions in heterogeneous catalysis. Here we report a theoretical study on an SCC of Ru3@Mo2CO2 MXene for N2-to-NH3 thermal conversion. Our results show that Ru3@Mo2CO2 can effectively activate N2 and promotes its conversion to NH3 through an association mechanism, in which the rate-determining step of NH2* + H* → NH3* has a low energy barrier of 1.29 eV. Especially, with the assistance of Mo2CO2 support, the positively charged Ru3 cluster active site can effectively adsorb and activate N2, leading to 0.74 |e| charge transfer from Ru3@Mo2CO2 to the adsorbed N2. The supported Ru3 also acts as an electron reservoir to regulate the charge transfer for various intermediate steps of ammonia synthesis. Microkinetic analysis shows that the turnover frequency (TOF) of the N2-to-NH3 conversion on Ru3@Mo2CO2 is as high as 1.45 × 10−2 s−1 site−1 at a selected thermodynamic condition of 48 bar and 700 K, the performance of which even surpasses those of the Ru B5 site and Fe3/θ-Al2O3(010) reported before. Our work provides a theoretical understanding on the high stability and catalytic mechanism of Ru3@Mo2CO2 and guidance for further designing and fabricating MXene-based metal SCCs for ammonia synthesis under mild conditions.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"8 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141770100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electronic perturbation of Cu catalysts surface is crucial for optimizing electrochemical CO2 reduction activity, yet still poses great challenges. Herein, nanostructured Cu nanowires (NW) with fine-tuned surface electronic structure are achieved via surface encapsulation with electron-withdrawing (–F) and -donating (–Me) group-functionalized graphdiynes (R-GDY, R = –F and –Me), and the resulting catalysts, denoted as R-GDY/Cu NW, display distinct CO2 reduction performances. In-situ electrochemical spectroscopy revealed that the *CO (a key intermediate of the CO2 reduction reaction) binding affinity and consequent *CO coverage positively correlate to the Cu surface oxidation state, leading to the favorable C–C coupling on F-GDY/Cu NW over Me-GDY/Cu NW. Electrochemical measurements corroborate the favorable C2H4 production with an optimum C2+ selectivity of 73.15% ± 2.5% observed for F-GDY/Cu NW, while the predominant CH4 production is favored by Me-GDY/Cu NW. Furthermore, leveraging the *Cu–OH/*CO ratio as a descriptor, mechanistic investigation reveals that the protonation of distinct adsorbed *CO facilitated by *Cu–OH is crucial for the selective generation of C2H4 and CH4 on F-GDY/Cu NW and Me-GDY/Cu NW, respectively.
{"title":"Electronic perturbation of Cu nanowire surfaces with functionalized graphdiyne for enhanced CO2 reduction reaction","authors":"Haiyuan Zou, Dongfang Cheng, Chao Tang, Wen Luo, Huatian Xiong, Hongliang Dong, Fan Li, Tao Song, Siyan Shu, Hao Dai, Ziang Cui, Zhouguang Lu, Lele Duan","doi":"10.1093/nsr/nwae253","DOIUrl":"https://doi.org/10.1093/nsr/nwae253","url":null,"abstract":"Electronic perturbation of Cu catalysts surface is crucial for optimizing electrochemical CO2 reduction activity, yet still poses great challenges. Herein, nanostructured Cu nanowires (NW) with fine-tuned surface electronic structure are achieved via surface encapsulation with electron-withdrawing (–F) and -donating (–Me) group-functionalized graphdiynes (R-GDY, R = –F and –Me), and the resulting catalysts, denoted as R-GDY/Cu NW, display distinct CO2 reduction performances. In-situ electrochemical spectroscopy revealed that the *CO (a key intermediate of the CO2 reduction reaction) binding affinity and consequent *CO coverage positively correlate to the Cu surface oxidation state, leading to the favorable C–C coupling on F-GDY/Cu NW over Me-GDY/Cu NW. Electrochemical measurements corroborate the favorable C2H4 production with an optimum C2+ selectivity of 73.15% ± 2.5% observed for F-GDY/Cu NW, while the predominant CH4 production is favored by Me-GDY/Cu NW. Furthermore, leveraging the *Cu–OH/*CO ratio as a descriptor, mechanistic investigation reveals that the protonation of distinct adsorbed *CO facilitated by *Cu–OH is crucial for the selective generation of C2H4 and CH4 on F-GDY/Cu NW and Me-GDY/Cu NW, respectively.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"142 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141770104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wei Li, Rizheng He, Xiaohui Yuan, Felix Schneider, Frederik Tilmann, Zhen Guo, Yongshun John Chen
The mechanism that causes the rapid uplift and active magmatism of the Hoh-Xil Basin in the northern Tibetan Plateau and hence the outward growth of the proto-plateau is highly debated, more specifically, over the relationship between deep dynamics and surface uplift. Due to inaccessibility the Hoh-Xil Basin remained uncovered by seismic networks until recently. Here, based on seismic arrays linearly across the Hoh-Xil Basin, we present a three-dimensional S-wave velocity (VS) model of the crust and uppermost mantle structure beneath the Tibetan Plateau from ambient noise tomography. This model exhibits widespread partially molten crust in the northern Tibetan Plateau but only isolated pockets in the south manifested as low-VS anomalies in the middle crust. The spatial correlation of the widespread low-VS anomalies with strong uppermost mantle low-VS anomalies and young exposed magmatic rocks in the Hoh-Xil Basin suggests that the plateau grew through lithospheric mantle removal and its driven magmatism.
关于造成青藏高原北部呼-锡盆地快速隆起和活跃岩浆活动，从而使原高原向外扩展的机制，尤其是深部动力学与地表隆起之间的关系，存在着激烈的争论。由于交通不便，直到最近，地震台网仍未发现呼-锡盆地。在此，我们基于线性横穿呼-锡盆地的地震阵列，通过环境噪声层析成像，提出了青藏高原下地壳和最上层地幔结构的三维 S 波速度（VS）模型。该模型显示了青藏高原北部广泛的部分熔融地壳，但在南部只有孤立的小块地壳，表现为中层地壳的低VS异常。广泛的低 VS 异常与最上层地幔低 VS 强异常以及呼-锡盆地年轻岩浆岩裸露的空间相关性表明，高原是通过岩石圈地幔剥离及其驱动的岩浆活动而生长的。
{"title":"Correlated crustal and mantle melting documents proto-tibetan Plateau growth","authors":"Wei Li, Rizheng He, Xiaohui Yuan, Felix Schneider, Frederik Tilmann, Zhen Guo, Yongshun John Chen","doi":"10.1093/nsr/nwae257","DOIUrl":"https://doi.org/10.1093/nsr/nwae257","url":null,"abstract":"The mechanism that causes the rapid uplift and active magmatism of the Hoh-Xil Basin in the northern Tibetan Plateau and hence the outward growth of the proto-plateau is highly debated, more specifically, over the relationship between deep dynamics and surface uplift. Due to inaccessibility the Hoh-Xil Basin remained uncovered by seismic networks until recently. Here, based on seismic arrays linearly across the Hoh-Xil Basin, we present a three-dimensional S-wave velocity (VS) model of the crust and uppermost mantle structure beneath the Tibetan Plateau from ambient noise tomography. This model exhibits widespread partially molten crust in the northern Tibetan Plateau but only isolated pockets in the south manifested as low-VS anomalies in the middle crust. The spatial correlation of the widespread low-VS anomalies with strong uppermost mantle low-VS anomalies and young exposed magmatic rocks in the Hoh-Xil Basin suggests that the plateau grew through lithospheric mantle removal and its driven magmatism.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"61 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141770102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shiguo Fu, Gaizhao Qin, Jinqiao Dong, Chen Yuan, Yan Liu, Li-Ming Yuan, Yong Cui
Capillary electrochromatography (CEC) is a rapidly emerging separation technique that merges the high separation efficiency of capillary electrophoresis with the exceptional selectivity of liquid chromatography. However, it remains a synthetic challenge to design functional chiral stationary phases (CSPs) with high chemical stability against acid and base in CEC enantioseparation. Here we demonstrate that incorporating chiral crown ethers into stable covalent organic frameworks (COFs) enable efficient and stable separations of racemates by CEC. This facilitates us to craft two three-dimensional chiral COFs (CCOFs) by polycondensation of a chiral 1,1'-binaphyl-20-crown-6-derived dialdehyde and tetraamines with diisopropyl substituents. Both feature a 11-fold interpenetrated diamond framework, characterized by tubular open channels decorated with chiral crown ethers serving as enantioselective recognition and binding sites. These frameworks demonstrate excellent stability in water, acid, and base, thanks to the presence of bulky iso-propyl groups that shield the dynamic imine linkages. Moreover, the precisely defined COF channels enhanced the accessibility of the enclosed crown ethers to the analytes while providing strong protection against harsh environments, rendering them suitable for CSPs in CEC separations. They can effectively separate some important enantiomers, including ketones, epoxides, and alkaline substances, when utilized as coatings on chiral columns, particularly facilitating the chiral separation of drugs. This study advances the application of COFs in electrochromatographic separations, expanding the scope of porous materials design and engineering to create COFs with targeted enantioselective properties.
{"title":"Construction of chiral crown ethers into robust covalent organic frameworks for electrochromatographic enantioseparation","authors":"Shiguo Fu, Gaizhao Qin, Jinqiao Dong, Chen Yuan, Yan Liu, Li-Ming Yuan, Yong Cui","doi":"10.1093/nsr/nwae256","DOIUrl":"https://doi.org/10.1093/nsr/nwae256","url":null,"abstract":"Capillary electrochromatography (CEC) is a rapidly emerging separation technique that merges the high separation efficiency of capillary electrophoresis with the exceptional selectivity of liquid chromatography. However, it remains a synthetic challenge to design functional chiral stationary phases (CSPs) with high chemical stability against acid and base in CEC enantioseparation. Here we demonstrate that incorporating chiral crown ethers into stable covalent organic frameworks (COFs) enable efficient and stable separations of racemates by CEC. This facilitates us to craft two three-dimensional chiral COFs (CCOFs) by polycondensation of a chiral 1,1'-binaphyl-20-crown-6-derived dialdehyde and tetraamines with diisopropyl substituents. Both feature a 11-fold interpenetrated diamond framework, characterized by tubular open channels decorated with chiral crown ethers serving as enantioselective recognition and binding sites. These frameworks demonstrate excellent stability in water, acid, and base, thanks to the presence of bulky iso-propyl groups that shield the dynamic imine linkages. Moreover, the precisely defined COF channels enhanced the accessibility of the enclosed crown ethers to the analytes while providing strong protection against harsh environments, rendering them suitable for CSPs in CEC separations. They can effectively separate some important enantiomers, including ketones, epoxides, and alkaline substances, when utilized as coatings on chiral columns, particularly facilitating the chiral separation of drugs. This study advances the application of COFs in electrochromatographic separations, expanding the scope of porous materials design and engineering to create COFs with targeted enantioselective properties.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"12 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141770099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This perspective summarizes the understanding about the local reaction environment in the electrocatalysis and underscores the influence of local environment due to its special location.
这一观点总结了对电催化过程中局部反应环境的理解，并强调了局部环境因其特殊位置而产生的影响。
{"title":"Understanding the local environment in electrocatalysis","authors":"Chaojie Chen, Yao Zheng, Shi-Zhang Qiao","doi":"10.1093/nsr/nwae250","DOIUrl":"https://doi.org/10.1093/nsr/nwae250","url":null,"abstract":"This perspective summarizes the understanding about the local reaction environment in the electrocatalysis and underscores the influence of local environment due to its special location.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"12 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141770101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
New fossil footprints from Beijing shows that four-foot animals already roamed the east side of supercontinent Pangea ~300 million years ago, proving land connections between North China Block and Pangea.
{"title":"Journey to the east: the oldest tetrapod fauna of east Pangea in early Permian","authors":"Jianye Chen, Jun Liu","doi":"10.1093/nsr/nwae249","DOIUrl":"https://doi.org/10.1093/nsr/nwae249","url":null,"abstract":"New fossil footprints from Beijing shows that four-foot animals already roamed the east side of supercontinent Pangea ~300 million years ago, proving land connections between North China Block and Pangea.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"49 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141770170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
He Wang, Xiaokang Liu, Yulong Zhao, Zhihu Sun, Yue Lin, Tao Yao, Hai-Long Jiang
While atomically precise metal nanoclusters (NCs) with unique structures and reactivity are very promising in catalysis, the spatial resistance caused by the surface ligands and structural instability significantly poses great challenges. In this work, Au25(Cys)18 NCs are encapsulated in multivariate metal-organic frameworks (MOFs) to afford Au25@M-MOF-74 (M = Zn, Ni, Co, Mg). By the MOF confinement, the Au25 NCs showcase much enhanced activity and stability in the intramolecular cascade reaction of 2-nitrobenzonitrile. Notably, the interaction between the metal nodes in M-MOF-74 and Au25(Cys)18 is able to suppress the free vibration of the surface ligands on the Au25 NCs and thereby improve the accessibility of Au sites; meanwhile, the stronger interactions lead to higher electron density and core expansion within Au25(Cys)18. As a result, the activity exhibits the trend of Au25@Ni-MOF-74 > Au25@Co-MOF-74 > Au25@Zn-MOF-74 > Au25@Mg-MOF-74, highlighting the crucial roles of microenvironment modulation around the Au25 NCs by interaction between the surface ligands and MOF hosts.
{"title":"Regulating interaction with surface ligands on Au25 nanoclusters by multivariate metal-organic framework hosts for boosting catalysis","authors":"He Wang, Xiaokang Liu, Yulong Zhao, Zhihu Sun, Yue Lin, Tao Yao, Hai-Long Jiang","doi":"10.1093/nsr/nwae252","DOIUrl":"https://doi.org/10.1093/nsr/nwae252","url":null,"abstract":"While atomically precise metal nanoclusters (NCs) with unique structures and reactivity are very promising in catalysis, the spatial resistance caused by the surface ligands and structural instability significantly poses great challenges. In this work, Au25(Cys)18 NCs are encapsulated in multivariate metal-organic frameworks (MOFs) to afford Au25@M-MOF-74 (M = Zn, Ni, Co, Mg). By the MOF confinement, the Au25 NCs showcase much enhanced activity and stability in the intramolecular cascade reaction of 2-nitrobenzonitrile. Notably, the interaction between the metal nodes in M-MOF-74 and Au25(Cys)18 is able to suppress the free vibration of the surface ligands on the Au25 NCs and thereby improve the accessibility of Au sites; meanwhile, the stronger interactions lead to higher electron density and core expansion within Au25(Cys)18. As a result, the activity exhibits the trend of Au25@Ni-MOF-74 > Au25@Co-MOF-74 > Au25@Zn-MOF-74 > Au25@Mg-MOF-74, highlighting the crucial roles of microenvironment modulation around the Au25 NCs by interaction between the surface ligands and MOF hosts.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"124 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141770106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Over the past two decades, Shu-Hong Yu's team has been focusing on the field of biomimetic materials, withmimetic targets include shells, pearls, wood, bone, fish scale, bamboo joint, lotus root silk and others.
{"title":"Biomimetic Materials Research, from Interest-driven to Society-serving: An interview with Shu-Hong Yu","authors":"Weijie Zhao","doi":"10.1093/nsr/nwae246","DOIUrl":"https://doi.org/10.1093/nsr/nwae246","url":null,"abstract":"Over the past two decades, Shu-Hong Yu's team has been focusing on the field of biomimetic materials, withmimetic targets include shells, pearls, wood, bone, fish scale, bamboo joint, lotus root silk and others.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"61 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141737361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Luming Wang, Song Wu, Zejuan Zhang, Jiankai Zhu, Luwei Zou, Bo Xu, Jiaqi Wu, Junzhi Zhu, Fei Xiao, Chenyin Jiao, Shenghai Pei, Jiaze Qin, Yu Zhou, Juan Xia, Zenghui Wang
Two-dimensional (2D) non-layered materials in many aspects differ from their layered counterparts, and the exploration of their physical properties has produced many intriguing findings. However, due to challenges in applying existing experimental techniques to such nanoscale samples, their thermal properties have remained largely uncharacterized, hindering further exploration and device applications using this promising material system. Here, we demonstrate an experimental study of thermal conduction in β-In2S3, a typical non-layered 2D material, using a resonant nanoelectromechanical systems (NEMS) platform. We devise a new two-degrees-of-freedom technique, more responsive and sensitive than Raman spectroscopy, to simultaneously determine both the thermal conductivity to be 3.7 Wm−1K−1 and its interfacial thermal conductance with SiO2 as 6.4 MWm−2K−1. Leveraging such unique thermal properties, we further demonstrate a record-high power-to-frequency responsivity of −447 ppm/μW in β-In2S3 NEMS sensors, the best among drumhead NEMS-based bolometers. Our findings offer an effective approach for studying thermal properties and exploring potential thermal applications of 2D non-layered materials.
{"title":"Investigating thermal properties of 2D non-layered material using a NEMS-based 2-DOF approach towards ultrahigh-performance bolometer","authors":"Luming Wang, Song Wu, Zejuan Zhang, Jiankai Zhu, Luwei Zou, Bo Xu, Jiaqi Wu, Junzhi Zhu, Fei Xiao, Chenyin Jiao, Shenghai Pei, Jiaze Qin, Yu Zhou, Juan Xia, Zenghui Wang","doi":"10.1093/nsr/nwae248","DOIUrl":"https://doi.org/10.1093/nsr/nwae248","url":null,"abstract":"Two-dimensional (2D) non-layered materials in many aspects differ from their layered counterparts, and the exploration of their physical properties has produced many intriguing findings. However, due to challenges in applying existing experimental techniques to such nanoscale samples, their thermal properties have remained largely uncharacterized, hindering further exploration and device applications using this promising material system. Here, we demonstrate an experimental study of thermal conduction in β-In2S3, a typical non-layered 2D material, using a resonant nanoelectromechanical systems (NEMS) platform. We devise a new two-degrees-of-freedom technique, more responsive and sensitive than Raman spectroscopy, to simultaneously determine both the thermal conductivity to be 3.7 Wm−1K−1 and its interfacial thermal conductance with SiO2 as 6.4 MWm−2K−1. Leveraging such unique thermal properties, we further demonstrate a record-high power-to-frequency responsivity of −447 ppm/μW in β-In2S3 NEMS sensors, the best among drumhead NEMS-based bolometers. Our findings offer an effective approach for studying thermal properties and exploring potential thermal applications of 2D non-layered materials.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"21 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141737138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The spin of electrons plays a vital role in chemical reactions and processes, and the excited state generated by the absorption of photons shows abundant spin-related phenomena. However, the importance of electron spin in photochemistry studies has been rarely mentioned or summarized. In this review, we briefly introduce the concept for spin photochemistry based on the spin multiplicity of excited state, which leads to the observation of various spin-related photophysical properties and photochemical reactivities. Then we focus on the recent advances in terms of light-induced magnetic properties, excited-state magneto-optical effects, and spin-dependent photochemical reactions. The review aims to provide a comprehensive overview to utilize the spin multiplicity of excited state in manipulating the above photophysical and photochemical processes. Finally, we discuss the existing challenges in the emerging field of spin photochemistry, and the future opportunities such as smart magnetic materials, optical information technology, and spin-enhanced photocatalysis.
{"title":"Spin-related excited-state phenomena in photochemistry","authors":"Chuang Zhang, Chen Ye, Jiannian Yao, Li-Zhu Wu","doi":"10.1093/nsr/nwae244","DOIUrl":"https://doi.org/10.1093/nsr/nwae244","url":null,"abstract":"The spin of electrons plays a vital role in chemical reactions and processes, and the excited state generated by the absorption of photons shows abundant spin-related phenomena. However, the importance of electron spin in photochemistry studies has been rarely mentioned or summarized. In this review, we briefly introduce the concept for spin photochemistry based on the spin multiplicity of excited state, which leads to the observation of various spin-related photophysical properties and photochemical reactivities. Then we focus on the recent advances in terms of light-induced magnetic properties, excited-state magneto-optical effects, and spin-dependent photochemical reactions. The review aims to provide a comprehensive overview to utilize the spin multiplicity of excited state in manipulating the above photophysical and photochemical processes. Finally, we discuss the existing challenges in the emerging field of spin photochemistry, and the future opportunities such as smart magnetic materials, optical information technology, and spin-enhanced photocatalysis.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"29 1","pages":""},"PeriodicalIF":20.6,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141737137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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