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2023 Volume 42 Issue 9
2023, 42(9): 100061
doi: 10.1016/j.cjsc.2023.100061
Abstract:
Glyme-based electrolytes are of great interest for rechargeable lithium metal batteries due to their high stability, low vapor pressure, and non-flammability. Understanding the solvation structures of these electrolytes at the atomic level will facilitate the design of new electrolytes with novel properties. Recently, classical molecular dynamics (CMD) and ab initio molecular dynamics (AIMD) have been applied to investigate electrolytes with complex solvation structures. On one hand, classical molecular dynamics (CMD) may not provide reliable results as it requires complex parameterization to ensure the accuracy of the classical force field. On the other hand, the time scale of AIMD is limited by the high cost of ab initio calculations, which causes that solvation structures from AIMD simulations depend on the initial configurations. In order to solve the dilemma, machine learning method is applied to accelerate AIMD, and the time scale of AIMD can be extended dramatically. In this work, we present a computational study on the solvation structures of triglyme (G3) based electrolytes by using machine learning molecular dynamics (MLMD). Firstly, we investigate the effects of density functionals on the accuracy of machine learning potential (MLP), and find that PBE-D3 shows better accuracy compared to BLYP-D3. Then, the densities of electrolytes with different concentration of LiTFSI are computed with MLMD, which shows good agreement with experiments. By analyzing the solvation structures of 1 ns MLMD trajectories, we found that Li+ prefers to coordinate with a G3 and a TFSI- in equimolar electrolytes. Our work demonstrates the significance of long-time scale MLMD simulations for clarifying the chemistry of non-ideal electrolytes.
Glyme-based electrolytes are of great interest for rechargeable lithium metal batteries due to their high stability, low vapor pressure, and non-flammability. Understanding the solvation structures of these electrolytes at the atomic level will facilitate the design of new electrolytes with novel properties. Recently, classical molecular dynamics (CMD) and ab initio molecular dynamics (AIMD) have been applied to investigate electrolytes with complex solvation structures. On one hand, classical molecular dynamics (CMD) may not provide reliable results as it requires complex parameterization to ensure the accuracy of the classical force field. On the other hand, the time scale of AIMD is limited by the high cost of ab initio calculations, which causes that solvation structures from AIMD simulations depend on the initial configurations. In order to solve the dilemma, machine learning method is applied to accelerate AIMD, and the time scale of AIMD can be extended dramatically. In this work, we present a computational study on the solvation structures of triglyme (G3) based electrolytes by using machine learning molecular dynamics (MLMD). Firstly, we investigate the effects of density functionals on the accuracy of machine learning potential (MLP), and find that PBE-D3 shows better accuracy compared to BLYP-D3. Then, the densities of electrolytes with different concentration of LiTFSI are computed with MLMD, which shows good agreement with experiments. By analyzing the solvation structures of 1 ns MLMD trajectories, we found that Li+ prefers to coordinate with a G3 and a TFSI- in equimolar electrolytes. Our work demonstrates the significance of long-time scale MLMD simulations for clarifying the chemistry of non-ideal electrolytes.
2023, 42(9): 100066
doi: 10.1016/j.cjsc.2023.100066
Abstract:
The process of photocatalysis, regarded as a promising approach for tackling the energy crisis and environmental pollution issues, is crucial for turning solar light into chemical resources. However, the solar-chemical conversion efficiency of typical semiconductor catalysts is still too low, so it is vital to figure out how to boost photocatalytic performance of semiconductors. Under visible light illumination, the local surface plasmon resonance (LSPR) induced by coinage metal would enhance the local electric field and improve photocatalytic performance of semiconductors, especially in the visible range. Therefore, its attachment to semiconductors has been regarded as an efficient strategy to improve photocatalytic performance. This paper reviews the latest research progress of plasmonic photocatalysis from theory to application. Starting from the excitation and relaxation of plasmons, four main mechanisms of plasmon-enhanced semiconductor photocatalysis are introduced, including enhanced light absorption and scattering, local electromagnetic field enhancement, improved hot carriers (HCs) injection and enhanced thermal effect. Secondly, the current mainstream plasmonic photocatalysts, such as monometallic, bimetallic and non-noble metal-based plasmonic catalysts, are reviewed. Finally, the applications of plasmonic photocatalysts in H2 production, CO2 reduction, and antibacterial are further summarized.
The process of photocatalysis, regarded as a promising approach for tackling the energy crisis and environmental pollution issues, is crucial for turning solar light into chemical resources. However, the solar-chemical conversion efficiency of typical semiconductor catalysts is still too low, so it is vital to figure out how to boost photocatalytic performance of semiconductors. Under visible light illumination, the local surface plasmon resonance (LSPR) induced by coinage metal would enhance the local electric field and improve photocatalytic performance of semiconductors, especially in the visible range. Therefore, its attachment to semiconductors has been regarded as an efficient strategy to improve photocatalytic performance. This paper reviews the latest research progress of plasmonic photocatalysis from theory to application. Starting from the excitation and relaxation of plasmons, four main mechanisms of plasmon-enhanced semiconductor photocatalysis are introduced, including enhanced light absorption and scattering, local electromagnetic field enhancement, improved hot carriers (HCs) injection and enhanced thermal effect. Secondly, the current mainstream plasmonic photocatalysts, such as monometallic, bimetallic and non-noble metal-based plasmonic catalysts, are reviewed. Finally, the applications of plasmonic photocatalysts in H2 production, CO2 reduction, and antibacterial are further summarized.
2023, 42(9): 100098
doi: 10.1016/j.cjsc.2023.100098
Abstract:
Nonlinear optical (NLO) crystals are key materials for solid-state lasers, which play an important role in modern science and technology. However, owing to the intrinsic limitation of functional building units (FBUs) in conventional compounds, it is difficult to surpass the performance of existing materials. Therefore, it is necessary to continuously explore new NLO-active FBUs to overcome the recent stagnant situation. Recently, a lot of new FBUs were discovered as NLO-active units in different wavelength ranges. Their contributions are confirmed by the performance of corresponding crystals. In this review, newly identified NLO-active units and corresponding NLO crystals are summarized and discussed in terms of crystal structure, NLO performance, and structure-property relationship. One can find that the heteroleptic coordinated tetrahedra and organic π-conjugated planar groups are the main source of new FUBs that will be a research hotspot in further research work. This review concludes the feasible directions on the exploration of new NLO crystals to satisfy the urgent requirements.
Nonlinear optical (NLO) crystals are key materials for solid-state lasers, which play an important role in modern science and technology. However, owing to the intrinsic limitation of functional building units (FBUs) in conventional compounds, it is difficult to surpass the performance of existing materials. Therefore, it is necessary to continuously explore new NLO-active FBUs to overcome the recent stagnant situation. Recently, a lot of new FBUs were discovered as NLO-active units in different wavelength ranges. Their contributions are confirmed by the performance of corresponding crystals. In this review, newly identified NLO-active units and corresponding NLO crystals are summarized and discussed in terms of crystal structure, NLO performance, and structure-property relationship. One can find that the heteroleptic coordinated tetrahedra and organic π-conjugated planar groups are the main source of new FUBs that will be a research hotspot in further research work. This review concludes the feasible directions on the exploration of new NLO crystals to satisfy the urgent requirements.
2023, 42(9): 100118
doi: 10.1016/j.cjsc.2023.100118
Abstract:
Lithium-ion batteries (LIBs) are a promising energy storage system for green energy applications. However, the use of liquid electrolytes in LIBs results in safety and lifespan issues. To address these challenges, researchers have been focusing on the development of all-solid-state batteries that use solid electrolytes. Unfortunately, traditional methods are time-consuming and expensive for exploring solid-state batteries, limiting their ability to keep up with growing social demand. In recent years, the development of big data has opened up new avenues for materials discovery, allowing for large-scale materials screening through computer simulations and machine learning models that can disclose the structure-activity relationship of materials. This review provides an overview of the basic procedures and common algorithms used in machine learning for designing solid-state batteries, with particular emphasis on recent research progress in applying machine learning to cathode materials and solid electrolytes, as well as predicting the condition of solid-state batteries. Additionally, this review offers a brief outlook on the challenges and opportunities facing machine learning methods in the realm of solid-state batteries.
Lithium-ion batteries (LIBs) are a promising energy storage system for green energy applications. However, the use of liquid electrolytes in LIBs results in safety and lifespan issues. To address these challenges, researchers have been focusing on the development of all-solid-state batteries that use solid electrolytes. Unfortunately, traditional methods are time-consuming and expensive for exploring solid-state batteries, limiting their ability to keep up with growing social demand. In recent years, the development of big data has opened up new avenues for materials discovery, allowing for large-scale materials screening through computer simulations and machine learning models that can disclose the structure-activity relationship of materials. This review provides an overview of the basic procedures and common algorithms used in machine learning for designing solid-state batteries, with particular emphasis on recent research progress in applying machine learning to cathode materials and solid electrolytes, as well as predicting the condition of solid-state batteries. Additionally, this review offers a brief outlook on the challenges and opportunities facing machine learning methods in the realm of solid-state batteries.
2023, 42(9): 100125
doi: 10.1016/j.cjsc.2023.100125
Abstract:
As important halogenating and oxidant agents, the synthesis and utilization of interhalogens are plagued by their purity problem, strong volatility and high reactivity. Herein, a flexible Cd-based metal-organic framework (MOF), {[Cd(1,4-bdc)(4-bpa)]·DMF}n (1, where 4-bpa = 1,2-bis(4-pyridyl)acetylene), was prepared and its corresponding activation species, [Cd(1,4-bdc)(4-bpa)]n (2), with moderate pore size and shape, acting as a crystal vessel, was applied to synthesize and store pure interhalogens. The synthesis of interhalogen was realized by quantitive transformation of halogen molecules incorporated in the pores of 2, which was confirmed by single-crystal X-ray diffraction and other structural characterizations. The embedded interhalogen molecules were stabilized by their interactions with the inner groups of the porous framework of 2 and released in polar solvent and utilized in iodocyclization of organic alcohols with high selectivity. This work not only opens a new door to the synthesis of pure interhalogens but also demonstrates powerful applications of MOF crystal vessels in realizing classic but important inorganic and organic reactions.
As important halogenating and oxidant agents, the synthesis and utilization of interhalogens are plagued by their purity problem, strong volatility and high reactivity. Herein, a flexible Cd-based metal-organic framework (MOF), {[Cd(1,4-bdc)(4-bpa)]·DMF}n (1, where 4-bpa = 1,2-bis(4-pyridyl)acetylene), was prepared and its corresponding activation species, [Cd(1,4-bdc)(4-bpa)]n (2), with moderate pore size and shape, acting as a crystal vessel, was applied to synthesize and store pure interhalogens. The synthesis of interhalogen was realized by quantitive transformation of halogen molecules incorporated in the pores of 2, which was confirmed by single-crystal X-ray diffraction and other structural characterizations. The embedded interhalogen molecules were stabilized by their interactions with the inner groups of the porous framework of 2 and released in polar solvent and utilized in iodocyclization of organic alcohols with high selectivity. This work not only opens a new door to the synthesis of pure interhalogens but also demonstrates powerful applications of MOF crystal vessels in realizing classic but important inorganic and organic reactions.
2023, 42(9): 100133
doi: 10.1016/j.cjsc.2023.100133
Abstract:
A simple one-step hydrothermal method is used to prepare an enzyme-free photoelectric combined glucose sensor based on TiO2NRs/FTO with low cost, sample two-electrode, and excellent detection. Under 380 nm light (0.5 mW cm–2 ) irradiation and a positive voltage, holes are accumulated on TiO2NRs surface, catalyzing glucose and forming a photocurrent without the need for an enzyme, such as Glucose oxidase (GOx). The designed sensor exhibits high sensitivity (about 0.96 μA mM–1 cm–2, without GOx) and excellent linear relationship in the glucose concentration range of 5–15 mML–1. The prepared glucose sensor performs better with a sensitivity of 1.48 μA mM–1 cm–2 when a certain amount of GOx is mixed in the detected solution. In addition, the sensor has excellent anti-interference resistance to non-reducing chitosan and reducing ascorbic acid with short response time (less than 5 s); thus, it can be used in quick detection with a double electrode system. This sensing device has the advantages of simple fabrication, easy storage, and reusability; therefore, it can be very promising in the portable and rapid monitoring of human blood glucose levels.
A simple one-step hydrothermal method is used to prepare an enzyme-free photoelectric combined glucose sensor based on TiO2NRs/FTO with low cost, sample two-electrode, and excellent detection. Under 380 nm light (0.5 mW cm–2 ) irradiation and a positive voltage, holes are accumulated on TiO2NRs surface, catalyzing glucose and forming a photocurrent without the need for an enzyme, such as Glucose oxidase (GOx). The designed sensor exhibits high sensitivity (about 0.96 μA mM–1 cm–2, without GOx) and excellent linear relationship in the glucose concentration range of 5–15 mML–1. The prepared glucose sensor performs better with a sensitivity of 1.48 μA mM–1 cm–2 when a certain amount of GOx is mixed in the detected solution. In addition, the sensor has excellent anti-interference resistance to non-reducing chitosan and reducing ascorbic acid with short response time (less than 5 s); thus, it can be used in quick detection with a double electrode system. This sensing device has the advantages of simple fabrication, easy storage, and reusability; therefore, it can be very promising in the portable and rapid monitoring of human blood glucose levels.
2023, 42(9): 100134
doi: 10.1016/j.cjsc.2023.100134
Abstract:
Lithium-sulfur (Li-S) batteries are recognized as promising high-energy-density storage systems. It is crucial to develop the compacted sulfur cathodes with high sulfur content and high sulfur loading for practical application. The metal-containing nanosheets are promising cathode matrix to mediate the accompanying problems, such as low sulfur utilization, unavoidable polysulfides shuttling and poor rate performance. Herein, we develop Ni-MOF-based strategy to fabricate nickel disulfide nanosheets on the reduced graphene oxide surface (NSG). Benefiting from nanosheets structure, strong polysulfides affinity, high electronic conductivity and superior electrocatalytic effect of NSG heterostructure, the resultant electrode exhibits high electrochemical performance with 0.021% capacity decay per cycle in 1000 cycles. Remarkably, the electrode with 88 wt% sulfur content and 5.9 mg cm-2 sulfur loading delivers reversible capacity of 945 mA h g-1, areal capacity of 6.1 mA h cm-2 and volumetric capacity of 997 mA h cm-3 at 0.5 C, which is comparable with the state-of-the-art those in the reported energy storage systems. This work provides methodology guidance for the development of the cathode matrix to achieve high-energy-density and long-life Li-S batteries.
Lithium-sulfur (Li-S) batteries are recognized as promising high-energy-density storage systems. It is crucial to develop the compacted sulfur cathodes with high sulfur content and high sulfur loading for practical application. The metal-containing nanosheets are promising cathode matrix to mediate the accompanying problems, such as low sulfur utilization, unavoidable polysulfides shuttling and poor rate performance. Herein, we develop Ni-MOF-based strategy to fabricate nickel disulfide nanosheets on the reduced graphene oxide surface (NSG). Benefiting from nanosheets structure, strong polysulfides affinity, high electronic conductivity and superior electrocatalytic effect of NSG heterostructure, the resultant electrode exhibits high electrochemical performance with 0.021% capacity decay per cycle in 1000 cycles. Remarkably, the electrode with 88 wt% sulfur content and 5.9 mg cm-2 sulfur loading delivers reversible capacity of 945 mA h g-1, areal capacity of 6.1 mA h cm-2 and volumetric capacity of 997 mA h cm-3 at 0.5 C, which is comparable with the state-of-the-art those in the reported energy storage systems. This work provides methodology guidance for the development of the cathode matrix to achieve high-energy-density and long-life Li-S batteries.
2023, 42(9): 100146
doi: 10.1016/j.cjsc.2023.100146
Abstract:
Adsorptive separation of acetylene (C2H2) from carbon dioxide (CO2) by adsorption is a viable method for producing high-purity C2H2 required for industrial applications. However, separating C2H2 and CO2 is challenging due to their extremely similar molecular sizes and physical properties. Metal-Organic Frameworks (MOFs), as a novel porous material with high specific surface area and tunable pore size, have shown great potential in the separation and purification of light hydrocarbons. Herein, we synthesized three isoreticular Al-MOFs (Al-TCPP, Al-TCPP(Co), and Al-TCPP(Fe)) by modulating metal ions at the porphyrin center, all of which can effectively separate C2H2/CO2. The addition of metal ions can regulate and improve the separation selectivity of C2H2/CO2. Compared with the parent Al-TCPP, the IAST selectivities of Al-TCPP(Co) and Al-TCPP(Fe) for equimolar C2H2/CO2 increased from 1.73 to 3.66 and 4.43, respectively. Breakthrough experiments validate their efficient separation of C2H2/CO2. Furthermore, they all exhibit excellent hydrothermal stability, laying the foundation for practical applications.
Adsorptive separation of acetylene (C2H2) from carbon dioxide (CO2) by adsorption is a viable method for producing high-purity C2H2 required for industrial applications. However, separating C2H2 and CO2 is challenging due to their extremely similar molecular sizes and physical properties. Metal-Organic Frameworks (MOFs), as a novel porous material with high specific surface area and tunable pore size, have shown great potential in the separation and purification of light hydrocarbons. Herein, we synthesized three isoreticular Al-MOFs (Al-TCPP, Al-TCPP(Co), and Al-TCPP(Fe)) by modulating metal ions at the porphyrin center, all of which can effectively separate C2H2/CO2. The addition of metal ions can regulate and improve the separation selectivity of C2H2/CO2. Compared with the parent Al-TCPP, the IAST selectivities of Al-TCPP(Co) and Al-TCPP(Fe) for equimolar C2H2/CO2 increased from 1.73 to 3.66 and 4.43, respectively. Breakthrough experiments validate their efficient separation of C2H2/CO2. Furthermore, they all exhibit excellent hydrothermal stability, laying the foundation for practical applications.
2023, 42(9): 100147
doi: 10.1016/j.cjsc.2023.100147
Abstract:
The acquisition of polymer-grade (99.95%) C2H4 poses a challenge due to the presence of ethane (C2H6) having similar physical and chemical properties. Consequently, the one-step purification of C2H4 becomes a crucial and demanding process. In this study, we synthesized ZIF-78 with a GME configuration using different metal sources (Zn, Co). Both substances have been identified as ethane-selective adsorbents with excellent thermal stability. The Brunauer Emmett Teller (BET) surface area of ZIF-78-Co (748 m2/g) surpasses that of ZIF-78-Zn (585 m2/g), and the former exhibits a higher Qst value for C2H6, resulting in enhanced adsorption capacity for C2H6 (50.61 cm3/g) and selectivity for C2H6/C2H4 (1.71) compared to ZIF-78-Zn (48.97 cm3/g, 1.46) at 298 K and 1 bar. Grand Canonical Monte Carlo (GCMC) calculations indicate that C2H6 has a stronger interaction with the ZIF-78-Co framework. Breakthrough experiments for the C2H6/C2H4 (50:50, V/V) mixture at 298 K and 1 bar demonstrate that ZIF-78-Co achieves separation in approximately 5 min/g, outperforming ZIF-78-Zn. And the separation time for ZIF-78-Co in the C2H6/C2H4 (10:90, V/V) mixture is 9 min/g. Furthermore, ZIF-78-Co exhibits excellent structural stability, thermal stability, water stability, and acid-base stability. Therefore, it holds promising prospects for practical industrial separation. Additionally, we hope that our findings inspire further experimentation on alternative metal ethane adsorbents.
The acquisition of polymer-grade (99.95%) C2H4 poses a challenge due to the presence of ethane (C2H6) having similar physical and chemical properties. Consequently, the one-step purification of C2H4 becomes a crucial and demanding process. In this study, we synthesized ZIF-78 with a GME configuration using different metal sources (Zn, Co). Both substances have been identified as ethane-selective adsorbents with excellent thermal stability. The Brunauer Emmett Teller (BET) surface area of ZIF-78-Co (748 m2/g) surpasses that of ZIF-78-Zn (585 m2/g), and the former exhibits a higher Qst value for C2H6, resulting in enhanced adsorption capacity for C2H6 (50.61 cm3/g) and selectivity for C2H6/C2H4 (1.71) compared to ZIF-78-Zn (48.97 cm3/g, 1.46) at 298 K and 1 bar. Grand Canonical Monte Carlo (GCMC) calculations indicate that C2H6 has a stronger interaction with the ZIF-78-Co framework. Breakthrough experiments for the C2H6/C2H4 (50:50, V/V) mixture at 298 K and 1 bar demonstrate that ZIF-78-Co achieves separation in approximately 5 min/g, outperforming ZIF-78-Zn. And the separation time for ZIF-78-Co in the C2H6/C2H4 (10:90, V/V) mixture is 9 min/g. Furthermore, ZIF-78-Co exhibits excellent structural stability, thermal stability, water stability, and acid-base stability. Therefore, it holds promising prospects for practical industrial separation. Additionally, we hope that our findings inspire further experimentation on alternative metal ethane adsorbents.
2023, 42(9): 100154
doi: 10.1016/j.cjsc.2023.100154
Abstract:
We here prepared the [Au13Ag12(PPh3)10(SR)5Cl2]2+ clusters ligated by thiolates with different side-groups, which exhibit significant differences in the photoluminescence properties.
We here prepared the [Au13Ag12(PPh3)10(SR)5Cl2]2+ clusters ligated by thiolates with different side-groups, which exhibit significant differences in the photoluminescence properties.
2023, 42(9): 100155
doi: 10.1016/j.cjsc.2023.100155
Abstract:
In conclusion, we have successfully synthesized a series of tin-oxo complexes using solvothermal strategies, yielding structurally diverse compounds. The crystal structures of these complexes were modulated through the incorporation of carboxylate and phosphonate ligands. Notably, we achieved the assembly of a three-dimensional cluster-based metal organic framework utilizing {Sn4} cluster units and niacin ligands with both N and O coordination sites. This framework exhibited a unique architecture with two Cu–C≡N– bridging motifs. Furthermore, we explored the influence of various precursors (such as (nBu)2SnO and nBuSn(O)OH), steric hindrances of phosphonate ligands, and solvent environments on the assembly process, resulting in the preparation of cage-dimers and ladders with distinct structural types. Analysis of the coordination patterns revealed that the carboxylate ligands adopt a staple-like coordination pattern, while the phosphonate ligands exhibit a tripod-like coordination pattern. Density of states analysis indicated that the carboxylate and phosphonate ligands contribute significantly to the electronic structure of these complexes. Overall, our findings demonstrate solvothermal synthetic strategies for the versatile self-assembly of tin-oxo complexes, providing a valuable platform for further exploration and application in this field.
In conclusion, we have successfully synthesized a series of tin-oxo complexes using solvothermal strategies, yielding structurally diverse compounds. The crystal structures of these complexes were modulated through the incorporation of carboxylate and phosphonate ligands. Notably, we achieved the assembly of a three-dimensional cluster-based metal organic framework utilizing {Sn4} cluster units and niacin ligands with both N and O coordination sites. This framework exhibited a unique architecture with two Cu–C≡N– bridging motifs. Furthermore, we explored the influence of various precursors (such as (nBu)2SnO and nBuSn(O)OH), steric hindrances of phosphonate ligands, and solvent environments on the assembly process, resulting in the preparation of cage-dimers and ladders with distinct structural types. Analysis of the coordination patterns revealed that the carboxylate ligands adopt a staple-like coordination pattern, while the phosphonate ligands exhibit a tripod-like coordination pattern. Density of states analysis indicated that the carboxylate and phosphonate ligands contribute significantly to the electronic structure of these complexes. Overall, our findings demonstrate solvothermal synthetic strategies for the versatile self-assembly of tin-oxo complexes, providing a valuable platform for further exploration and application in this field.
