Dorothea Scheunemann, Emmy Järsvall, Jian Liu, D. Beretta, S. Fabiano, M. Caironi, M. Kemerink, Christian Müller
Research on conjugated polymers for thermoelectric applications has made tremendous progress in recent years, which is accompanied by surging interest in molecular doping as a means to achieve the high electrical conductivities that are required. A detailed understanding of the complex relationship between the doping process, the structural as well as energetic properties of the polymer films, and the resulting thermoelectric behavior is slowly emerging. This review summarizes recent developments and strategies that permit enhancing the electrical conductivity of p- and n-type conjugated polymers via molecular doping. The impact of the chemical design of both the polymer and the dopant, the processing conditions, and the resulting nanostructure on the doping efficiency and stability of the doped state are discussed. Attention is paid to the interdependence of the electrical and thermal transport characteristics of semiconductor host-dopant systems and the Seebeck coefficient. Strategies that permit to improve the thermoelectric performance, such as an uniaxial alignment of the polymer backbone in both bulk and thin film geometries, manipulation of the dielectric constant of the polymer, and the variation of the dopant size, are explored. A combination of theory and experiment is predicted to yield new chemical design principles and processing schemes that will ultimately give rise to the next generation of organic thermoelectric materials.
{"title":"Charge transport in doped conjugated polymers for organic thermoelectrics","authors":"Dorothea Scheunemann, Emmy Järsvall, Jian Liu, D. Beretta, S. Fabiano, M. Caironi, M. Kemerink, Christian Müller","doi":"10.1063/5.0080820","DOIUrl":"https://doi.org/10.1063/5.0080820","url":null,"abstract":"Research on conjugated polymers for thermoelectric applications has made tremendous progress in recent years, which is accompanied by surging interest in molecular doping as a means to achieve the high electrical conductivities that are required. A detailed understanding of the complex relationship between the doping process, the structural as well as energetic properties of the polymer films, and the resulting thermoelectric behavior is slowly emerging. This review summarizes recent developments and strategies that permit enhancing the electrical conductivity of p- and n-type conjugated polymers via molecular doping. The impact of the chemical design of both the polymer and the dopant, the processing conditions, and the resulting nanostructure on the doping efficiency and stability of the doped state are discussed. Attention is paid to the interdependence of the electrical and thermal transport characteristics of semiconductor host-dopant systems and the Seebeck coefficient. Strategies that permit to improve the thermoelectric performance, such as an uniaxial alignment of the polymer backbone in both bulk and thin film geometries, manipulation of the dielectric constant of the polymer, and the variation of the dopant size, are explored. A combination of theory and experiment is predicted to yield new chemical design principles and processing schemes that will ultimately give rise to the next generation of organic thermoelectric materials.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47507645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Light energy can be harnessed by photosensitizers or photocatalysts so that some chemical reactions can be carried out under milder conditions compared to the traditional heat-driven processes. To facilitate the photo-driven reactions, a large variety of chromophores that are operated via charge transfer excitations have been reported because of their typically longer excited-state lifetimes, which are the key to the downstream photochemical processes. Although both metal-to-ligand charge transfers and ligand-to-metal charge transfers are well-established light absorption pathways; the former has been widely adopted in photocatalysis, whereas the latter has recently taken on greater importance in photosensitization applications. In this article, we review the latest developments on ligand-to-metal charge transfer photosensitization by molecular complexes across the periodic table by focusing homogeneous photocatalysis and the use of photophysical measurements and computational calculations to understand the electronic structures, photochemical processes, structure–activity relationships, and reaction mechanisms. We also present our perspectives on the possible future developments in the field.
{"title":"Emergence of ligand-to-metal charge transfer in homogeneous photocatalysis and photosensitization","authors":"Chenfei Li, X. Kong, Z. Tan, C. Yang, Han Sen Soo","doi":"10.1063/5.0086718","DOIUrl":"https://doi.org/10.1063/5.0086718","url":null,"abstract":"Light energy can be harnessed by photosensitizers or photocatalysts so that some chemical reactions can be carried out under milder conditions compared to the traditional heat-driven processes. To facilitate the photo-driven reactions, a large variety of chromophores that are operated via charge transfer excitations have been reported because of their typically longer excited-state lifetimes, which are the key to the downstream photochemical processes. Although both metal-to-ligand charge transfers and ligand-to-metal charge transfers are well-established light absorption pathways; the former has been widely adopted in photocatalysis, whereas the latter has recently taken on greater importance in photosensitization applications. In this article, we review the latest developments on ligand-to-metal charge transfer photosensitization by molecular complexes across the periodic table by focusing homogeneous photocatalysis and the use of photophysical measurements and computational calculations to understand the electronic structures, photochemical processes, structure–activity relationships, and reaction mechanisms. We also present our perspectives on the possible future developments in the field.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47561478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photoredox catalysis has been prominent in many applications, including solar fuels, organic synthesis, and polymer chemistry. Photocatalytic activity directly depends on the photophysical and electrochemical properties of photocatalysts in both the ground state and excited state. Controlling those properties, therefore, is imperative to achieve the desired photocatalytic activity. Redox potential is one important factor that impacts both the thermodynamic and kinetic aspects of key elementary steps in photoredox catalysis. In many challenging reactions in organic synthesis, high redox potentials of the substrates hamper the reaction, leading to slow conversion. Thus, the development of photocatalysts with extreme redox potentials, accompanied by potent reducing or oxidizing power, is required to execute high-yielding thermodynamically demanding reactions. In this review, we will introduce strategies for accessing extreme redox potentials in photocatalytic transformations. These include molecular design strategies for preparing photosensitizers that are exceptionally strong ground-state or excited-state reductants or oxidants, highlighting both organic and metal-based photosensitizers. We also outline methodological approaches for accessing extreme redox potentials, using two-photon activation, or combined electrochemical/photochemical strategies to generate potent redox reagents from precursors that have milder potentials.
{"title":"Strategies for accessing photosensitizers with extreme redox potentials","authors":"Dooyoung Kim, Thomas S. Teets","doi":"10.1063/5.0084554","DOIUrl":"https://doi.org/10.1063/5.0084554","url":null,"abstract":"Photoredox catalysis has been prominent in many applications, including solar fuels, organic synthesis, and polymer chemistry. Photocatalytic activity directly depends on the photophysical and electrochemical properties of photocatalysts in both the ground state and excited state. Controlling those properties, therefore, is imperative to achieve the desired photocatalytic activity. Redox potential is one important factor that impacts both the thermodynamic and kinetic aspects of key elementary steps in photoredox catalysis. In many challenging reactions in organic synthesis, high redox potentials of the substrates hamper the reaction, leading to slow conversion. Thus, the development of photocatalysts with extreme redox potentials, accompanied by potent reducing or oxidizing power, is required to execute high-yielding thermodynamically demanding reactions. In this review, we will introduce strategies for accessing extreme redox potentials in photocatalytic transformations. These include molecular design strategies for preparing photosensitizers that are exceptionally strong ground-state or excited-state reductants or oxidants, highlighting both organic and metal-based photosensitizers. We also outline methodological approaches for accessing extreme redox potentials, using two-photon activation, or combined electrochemical/photochemical strategies to generate potent redox reagents from precursors that have milder potentials.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45886176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Petrone, F. Perrella, Federico Coppola, Luigi Crisci, Greta Donati, P. Cimino, N. Rega
Light induces non-equilibrium time evolving molecular phenomena. The computational modeling of photo-induced processes in large systems, embedded in complex environments (i.e., solutions, proteins, materials), demands for a quantum and statistical mechanic treatment to achieve the required accuracy in the description of both the excited-state energy potentials and the choice of the initial conditions for dynamical simulations. On the other hand, the theoretical investigation on the atomistic scale of times and sizes of the ultrafast photo-induced reactivity and non-equilibrium relaxation dynamics right upon excitation requests tailored computational protocols. These methods often exploit hierarchic computation schemes, where a large part of the degrees of freedom are required to be treated explicitly to achieve the right accuracy. Additionally, part of the explicit system needs to be treated at ab initio level, where density functional theory, using hybrid functionals, represents a good compromise between accuracy and computational cost, when proton transfers, non-covalent interactions, and hydrogen bond dynamics play important roles. Thus, the modeling strategies presented in this review stress the importance of hierarchical quantum/molecular mechanics with effective non-periodic boundary conditions and efficient phase-sampling schemes to achieve chemical accuracy in ultrafast time-resolved spectroscopy and photo-induced phenomena. These approaches can allow explicit and accurate treatment of molecule/environment interactions, including also the electrostatic and dispersion forces of the bulk. At the same time, the specificities of the different case studies of photo-induced phenomena in solutions and biological environments are highlighted and discussed, with special attention to the computational and modeling challenges.
{"title":"Ultrafast photo-induced processes in complex environments: The role of accuracy in excited-state energy potentials and initial conditions","authors":"A. Petrone, F. Perrella, Federico Coppola, Luigi Crisci, Greta Donati, P. Cimino, N. Rega","doi":"10.1063/5.0085512","DOIUrl":"https://doi.org/10.1063/5.0085512","url":null,"abstract":"Light induces non-equilibrium time evolving molecular phenomena. The computational modeling of photo-induced processes in large systems, embedded in complex environments (i.e., solutions, proteins, materials), demands for a quantum and statistical mechanic treatment to achieve the required accuracy in the description of both the excited-state energy potentials and the choice of the initial conditions for dynamical simulations. On the other hand, the theoretical investigation on the atomistic scale of times and sizes of the ultrafast photo-induced reactivity and non-equilibrium relaxation dynamics right upon excitation requests tailored computational protocols. These methods often exploit hierarchic computation schemes, where a large part of the degrees of freedom are required to be treated explicitly to achieve the right accuracy. Additionally, part of the explicit system needs to be treated at ab initio level, where density functional theory, using hybrid functionals, represents a good compromise between accuracy and computational cost, when proton transfers, non-covalent interactions, and hydrogen bond dynamics play important roles. Thus, the modeling strategies presented in this review stress the importance of hierarchical quantum/molecular mechanics with effective non-periodic boundary conditions and efficient phase-sampling schemes to achieve chemical accuracy in ultrafast time-resolved spectroscopy and photo-induced phenomena. These approaches can allow explicit and accurate treatment of molecule/environment interactions, including also the electrostatic and dispersion forces of the bulk. At the same time, the specificities of the different case studies of photo-induced phenomena in solutions and biological environments are highlighted and discussed, with special attention to the computational and modeling challenges.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58563775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Forrest, G. Verma, Yingxiang Ye, Junyu Ren, Shengqian Ma, Tony Pham, Brian Space
Recently, there has been significant interest in methane as an abundant and cleaner burning alternative to fossil fuels. Consequently, the design of media capable of the storage of methane under practical conditions has become an area of significant interest to the scientific community. While metal−organic frameworks have seen pronounced examination for this application, flexible metal−organic framework variants have been little examined despite having tremendous promise for methane storage applications. This work provides an overview of the current state of the art regarding the investigation of these systems for the purpose of providing a baseline for future research.
{"title":"Methane storage in flexible and dynamical metal–organic frameworks","authors":"K. Forrest, G. Verma, Yingxiang Ye, Junyu Ren, Shengqian Ma, Tony Pham, Brian Space","doi":"10.1063/5.0072805","DOIUrl":"https://doi.org/10.1063/5.0072805","url":null,"abstract":"Recently, there has been significant interest in methane as an abundant and cleaner burning alternative to fossil fuels. Consequently, the design of media capable of the storage of methane under practical conditions has become an area of significant interest to the scientific community. While metal−organic frameworks have seen pronounced examination for this application, flexible metal−organic framework variants have been little examined despite having tremendous promise for methane storage applications. This work provides an overview of the current state of the art regarding the investigation of these systems for the purpose of providing a baseline for future research.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42040597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photogenerated spin-correlated radical pairs (SCRPs) in electron donor–bridge–acceptor (D–B–A) molecules can act as molecular qubits and inherently spin qubit pairs. SCRPs can take singlet and triplet spin states, comprising the quantum superposition state. Their synthetic accessibility and well-defined structures, together with their ability to be prepared in an initially pure, entangled spin state and optical addressability, make them one of the promising avenues for advancing quantum information science. Coherence between two spin states and spin selective electron transfer reactions form the foundation of using SCRPs as qubits for sensing. We can exploit the unique sensitivity of the spin dynamics of SCRPs to external magnetic fields for sensing applications including resolution-enhanced imaging, magnetometers, and magnetic switch. Molecular quantum sensors, if realized, can provide new technological developments beyond what is possible with classical counterparts. While the community of spin chemistry has actively investigated magnetic field effects on chemical reactions via SCRPs for several decades, we have not yet fully exploited the synthetic tunability of molecular systems to our advantage. This review offers an introduction to the photogenerated SCRPs-based molecular qubits for quantum sensing, aiming to lay the foundation for researchers new to the field and provide a basic reference for researchers active in the field. We focus on the basic principles necessary to construct molecular qubits based on SCRPs and the examples in quantum sensing explored to date from the perspective of the experimentalist.
{"title":"Molecular qubits based on photogenerated spin-correlated radical pairs for quantum sensing","authors":"Tomoyasu Mani","doi":"10.1063/5.0084072","DOIUrl":"https://doi.org/10.1063/5.0084072","url":null,"abstract":"Photogenerated spin-correlated radical pairs (SCRPs) in electron donor–bridge–acceptor (D–B–A) molecules can act as molecular qubits and inherently spin qubit pairs. SCRPs can take singlet and triplet spin states, comprising the quantum superposition state. Their synthetic accessibility and well-defined structures, together with their ability to be prepared in an initially pure, entangled spin state and optical addressability, make them one of the promising avenues for advancing quantum information science. Coherence between two spin states and spin selective electron transfer reactions form the foundation of using SCRPs as qubits for sensing. We can exploit the unique sensitivity of the spin dynamics of SCRPs to external magnetic fields for sensing applications including resolution-enhanced imaging, magnetometers, and magnetic switch. Molecular quantum sensors, if realized, can provide new technological developments beyond what is possible with classical counterparts. While the community of spin chemistry has actively investigated magnetic field effects on chemical reactions via SCRPs for several decades, we have not yet fully exploited the synthetic tunability of molecular systems to our advantage. This review offers an introduction to the photogenerated SCRPs-based molecular qubits for quantum sensing, aiming to lay the foundation for researchers new to the field and provide a basic reference for researchers active in the field. We focus on the basic principles necessary to construct molecular qubits based on SCRPs and the examples in quantum sensing explored to date from the perspective of the experimentalist.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42131592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The bulk photovoltaic effect (BPVE) occurs in solids with broken inversion symmetry and refers to DC generation due to uniform illumination, without the need of heterostructures or interfaces, a feature that is distinct from the traditional photovoltaic effect. Its existence has been demonstrated almost 50 years ago, but predictive theories only appeared in the last ten years, allowing for the identification of different mechanisms and the determination of their relative importance in real materials. It is now generally accepted that there is an intrinsic mechanism that is insensitive to scattering, called shift current, where first-principles calculations can now give highly accurate predictions. Another important but more extrinsic mechanism, called ballistic current, is also attracting a great deal of attention, but due to the complicated scattering processes, its numerical calculation for real materials is only made possible quite recently. In addition, an intrinsic ballistic current, usually referred to as injection current, will appear under circularly polarized light and has wide application in experiments. In this review, experiments that are pertinent to the theory development are reviewed, and a significant portion is devoted to discussing the recent progress in the theories of BPVE and their numerical implementations. As a demonstration of the capability of the newly developed theories, a brief review of the materials' design strategies enabled by the theory development is given. Finally, remaining questions in the BPVE field and possible future directions are discussed to inspire further investigations.
{"title":"Recent progress in the theory of bulk photovoltaic effect","authors":"Zhenbang Dai, A. Rappe","doi":"10.1063/5.0101513","DOIUrl":"https://doi.org/10.1063/5.0101513","url":null,"abstract":"The bulk photovoltaic effect (BPVE) occurs in solids with broken inversion symmetry and refers to DC generation due to uniform illumination, without the need of heterostructures or interfaces, a feature that is distinct from the traditional photovoltaic effect. Its existence has been demonstrated almost 50 years ago, but predictive theories only appeared in the last ten years, allowing for the identification of different mechanisms and the determination of their relative importance in real materials. It is now generally accepted that there is an intrinsic mechanism that is insensitive to scattering, called shift current, where first-principles calculations can now give highly accurate predictions. Another important but more extrinsic mechanism, called ballistic current, is also attracting a great deal of attention, but due to the complicated scattering processes, its numerical calculation for real materials is only made possible quite recently. In addition, an intrinsic ballistic current, usually referred to as injection current, will appear under circularly polarized light and has wide application in experiments. In this review, experiments that are pertinent to the theory development are reviewed, and a significant portion is devoted to discussing the recent progress in the theories of BPVE and their numerical implementations. As a demonstration of the capability of the newly developed theories, a brief review of the materials' design strategies enabled by the theory development is given. Finally, remaining questions in the BPVE field and possible future directions are discussed to inspire further investigations.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45550893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kiran Kuruvinashetti, Junnan Li, Yuxuan Zhang, Hossein Bemana, Morgan McKee, N. Kornienko
The development of electrochemical technologies is becoming increasingly important due to their growing part in renewable energy conversion and storage. Within this context, metal organic frameworks (MOFs) are finding an important role as electrocatalysts. Specifically, their molecularly defined structure across several lengths scales endows them functionality not accessible with conventional heterogeneous catalysts. To this end, this perspective will focus on the unique features within MOFs and their analogs that enable them to carry out electrocatalytic reactions in unique ways to synthesize fuels and value-added chemicals from abundant building blocks like CO2 and N2. We start with a brief overview of the initial advent of MOF electrocatalysts prior to moving to overview the forefront of the field of MOF-based electrosynthesis. The main discussion focuses on three principal directions in MOF-based electrosynthesis: multifunctional active sites, electronic modulation, and catalytic microenvironments. To conclude, we identify several challenges in the next stage of MOF electrocatalyst development and offer several key directions to take as the field matures.
{"title":"Emerging opportunities with metal-organic framework electrosynthetic platforms","authors":"Kiran Kuruvinashetti, Junnan Li, Yuxuan Zhang, Hossein Bemana, Morgan McKee, N. Kornienko","doi":"10.1063/5.0090147","DOIUrl":"https://doi.org/10.1063/5.0090147","url":null,"abstract":"The development of electrochemical technologies is becoming increasingly important due to their growing part in renewable energy conversion and storage. Within this context, metal organic frameworks (MOFs) are finding an important role as electrocatalysts. Specifically, their molecularly defined structure across several lengths scales endows them functionality not accessible with conventional heterogeneous catalysts. To this end, this perspective will focus on the unique features within MOFs and their analogs that enable them to carry out electrocatalytic reactions in unique ways to synthesize fuels and value-added chemicals from abundant building blocks like CO2 and N2. We start with a brief overview of the initial advent of MOF electrocatalysts prior to moving to overview the forefront of the field of MOF-based electrosynthesis. The main discussion focuses on three principal directions in MOF-based electrosynthesis: multifunctional active sites, electronic modulation, and catalytic microenvironments. To conclude, we identify several challenges in the next stage of MOF electrocatalyst development and offer several key directions to take as the field matures.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43282765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The time-dependent exchange–correlation potential has the unusual task of directing fictitious non-interacting electrons to move with exactly the same probability density as true interacting electrons. This has intriguing implications for its structure, especially in the non-perturbative regime, leading to step and peak features that cannot be captured by bootstrapping any ground-state functional approximation. We review what has been learned about these features in the exact exchange–correlation potential of time-dependent density functional theory in the past decade or so and implications for the performance of simulations when electrons are driven far from any ground state.
{"title":"The exact exchange–correlation potential in time-dependent density functional theory: Choreographing electrons with steps and peaks","authors":"D. Dar, L. Lacombe, N. Maitra","doi":"10.1063/5.0096627","DOIUrl":"https://doi.org/10.1063/5.0096627","url":null,"abstract":"The time-dependent exchange–correlation potential has the unusual task of directing fictitious non-interacting electrons to move with exactly the same probability density as true interacting electrons. This has intriguing implications for its structure, especially in the non-perturbative regime, leading to step and peak features that cannot be captured by bootstrapping any ground-state functional approximation. We review what has been learned about these features in the exact exchange–correlation potential of time-dependent density functional theory in the past decade or so and implications for the performance of simulations when electrons are driven far from any ground state.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46055099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hydrogen production from water via photocatalytic water splitting has attracted great interest due to the increasing challenge from energy and environment. The light harvest, electron–hole separation, and catalytic activity are keys to enhance the efficiency of solar energy utilization, which stimulates the development of high-performance photocatalysts. In recent years, two-dimensional (2D) materials have attracted much attention due to their extremely large specific surface area, shortened carrier migration path, and excellent optical properties, but it is still a challenge to realize overall water splitting under visible light with 2D material photocatalysts experimentally. Density functional theory-based first-principles calculations provide a quicker and lower cost approach in material design than experimental exploration. In this review, recent advances in design of 2D material photocatalysts, including metal-containing, metal-free, and heterojunction materials, for photocatalytic water splitting are presented from a theoretical perspective. Future opportunities and challenges in theoretical design of 2D material photocatalysts toward overall water splitting are also included.
{"title":"Theoretical design of two-dimensional visible light-driven photocatalysts for overall water splitting","authors":"Cen-Feng Fu, Xiaojun Wu, Jinlong Yang","doi":"10.1063/5.0079803","DOIUrl":"https://doi.org/10.1063/5.0079803","url":null,"abstract":"Hydrogen production from water via photocatalytic water splitting has attracted great interest due to the increasing challenge from energy and environment. The light harvest, electron–hole separation, and catalytic activity are keys to enhance the efficiency of solar energy utilization, which stimulates the development of high-performance photocatalysts. In recent years, two-dimensional (2D) materials have attracted much attention due to their extremely large specific surface area, shortened carrier migration path, and excellent optical properties, but it is still a challenge to realize overall water splitting under visible light with 2D material photocatalysts experimentally. Density functional theory-based first-principles calculations provide a quicker and lower cost approach in material design than experimental exploration. In this review, recent advances in design of 2D material photocatalysts, including metal-containing, metal-free, and heterojunction materials, for photocatalytic water splitting are presented from a theoretical perspective. Future opportunities and challenges in theoretical design of 2D material photocatalysts toward overall water splitting are also included.","PeriodicalId":72559,"journal":{"name":"Chemical physics reviews","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48128401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}