1
|
Porous silicon surface modification via a microwave-induced in situ cyclic disulfide (S-S) cleavage and Si-S bond formation. Colloids Surf B Biointerfaces 2023; 222:113055. [PMID: 36463610 DOI: 10.1016/j.colsurfb.2022.113055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 11/15/2022] [Accepted: 11/22/2022] [Indexed: 11/27/2022]
Abstract
Porous silicon (pSi) materials have gained a great deal of attention from various research fields, and their surface-functionalization is one of the critical points for their applications. In this study, a new surface modification method of Si-H-terminated pSi materials via microwave-induced Si-S bond formation is disclosed. The silicon hydride (Si-H) functionality on the pSi surface could react with the 5-membered cyclic disulfide (S-S) compound (DL-α-lipoic acid in this study) by microwave-induced in situ S-S bond cleavage and Si-S bond formation. This surface chemistry is fast responsive (<10 min) and more efficient than other methods such as vortexing, heating stirring, or ultrasonication. The reaction maintains the primary porous structure of pSi materials including pSi wafer, pSi rugate filer, and pSi nanoparticles. An additional functional group such as carboxylic acid is demonstrated to be readily introducible on the pSi surface for further applications. Overall, this study has successfully demonstrated the porous silicon surface modification via a microwave-induced in situ cyclic disulfide (S-S) cleavage and Si-S bond formation.
Collapse
|
2
|
Chen Y, Yao L, Chen X, Jin J, Wu M, Wang Q, Zha W, Wen Z. Double-Faced Bond Coupling to Induce an Ultrastable Lithium/Li 6PS 5Cl Interface for High-Performance All-Solid-State Batteries. ACS APPLIED MATERIALS & INTERFACES 2022; 14:11950-11961. [PMID: 35193356 DOI: 10.1021/acsami.1c24506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Sulfide-type solid electrolytes (SSEs) are supposed to be preferential candidates for all-solid-state Li metal batteries (ASSLMBs) due to their satisfactory Li+ conductivity and preferable mechanical stiffness. Nonetheless, the poor stability between the Li anode and SSEs and uncontrolled Li dendrite growth severely restrict their commercial application. Herein, an amphiphilic LixSiOy-enriched solid electrolyte interphase (SEI) as a "Janus" layer was first introduced at the Li/SSEs interface, and it exhibited bond coupling reactivity with both the Li anode and SSEs by forming Li-S, Li-O-Si, and Si-S covalent bonds, which is called the pincer effect. In addition to the physical isolation of Li and SSEs to prevent side reactions between them, LixSiOy with high ionic conductivity offers abundant and evenly distributed transport channels for fast Li+ migration. As evidenced by in situ microscopy, the high-strength anodic interface constructed by the pincer effect and in situ decomposition mentioned above is free from mechanical damage during the Li plating/stripping. As a result, the symmetric cells exert an outstanding cycling performance for over 2000 h at 0.2 mA cm-2 and even 500 h at 0.5 mA cm-2 without evident resistance growth. The artificial SEI layer with the pincer effect and its effective application in interfacial stabilization put forward a new perspective for the commercialization of ASSLMBs.
Collapse
Affiliation(s)
- Ya Chen
- CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Science, Beijing 100049, P. R. China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, P. R. China
| | - Liu Yao
- CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Science, Beijing 100049, P. R. China
| | - Xiaodong Chen
- College of Chemistry & Chemical Engineering, Shaoxing University, Shaoxing 312000, P. R. China
| | - Jun Jin
- CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Science, Beijing 100049, P. R. China
- State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
| | - Meifen Wu
- CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Science, Beijing 100049, P. R. China
- State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
| | - Qing Wang
- CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Science, Beijing 100049, P. R. China
| | - Wenping Zha
- CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Science, Beijing 100049, P. R. China
| | - Zhaoyin Wen
- CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Science, Beijing 100049, P. R. China
- State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China
| |
Collapse
|
3
|
Cai W, Bullerjahn JT, Lallemang M, Kroy K, Balzer BN, Hugel T. Angle-dependent strength of a single chemical bond by stereographic force spectroscopy. Chem Sci 2022; 13:5734-5740. [PMID: 35694336 PMCID: PMC9117962 DOI: 10.1039/d2sc01077a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 04/13/2022] [Indexed: 11/21/2022] Open
Abstract
A wealth of chemical bonds and polymers have been studied with single-molecule force spectroscopy, usually by applying a force perpendicular to the anchoring surface. However, the direction-dependence of the bond strength lacks fundamental understanding. Here we establish stereographic force spectroscopy to study the single-bond strength for various pulling angles. Surprisingly, we find that the apparent bond strength increases with increasing pulling angle relative to the anchoring surface normal, indicating a sturdy mechanical anisotropy of a chemical bond. This finding can be rationalized by a fixed pathway for the rupture of the bond, resulting in an effective projection of the applied pulling force onto a nearly fixed rupture direction. Our study is fundamental for the molecular understanding of the role of the direction of force application in molecular adhesion and friction. It is also a prerequisite for the nanoscale tailoring of the anisotropic strength of bottom-up designed materials. Stereographic force spectroscopy reveals that a chemical bond ruptures along a fixed pathway such that the apparent bond strength strongly depends on the angle of force application.![]()
Collapse
Affiliation(s)
- Wanhao Cai
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Jakob T. Bullerjahn
- Department of Theoretical Biophysics, Max Planck Institute of Biophysics, Max-von-Laue-Straße 3, 60438, Frankfurt am Main, Germany
| | - Max Lallemang
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
- Cluster of Excellence livMatS@FIT – Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110, Freiburg, Germany
| | - Klaus Kroy
- Institute for Theoretical Physics, Leipzig University, Brüderstraße 16, 04103, Leipzig, Germany
| | - Bizan N. Balzer
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
- Cluster of Excellence livMatS@FIT – Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110, Freiburg, Germany
- Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, 79104, Freiburg, Germany
| | - Thorsten Hugel
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
- Cluster of Excellence livMatS@FIT – Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110, Freiburg, Germany
| |
Collapse
|
4
|
Wang F, Chen Y, Rao W, Shen SS, Wang SY. Cu-catalyzed efficient construction of S (Se)-containing functional organosilicon compounds. Chem Commun (Camb) 2022; 58:12564-12567. [DOI: 10.1039/d2cc04512e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A Cu-catalyzed cascade reaction of four-membered silacyclobutanes (SCBs) and thiosulfonates to construct S (Se)-containing organosilicon compounds is described.
Collapse
Affiliation(s)
- Fei Wang
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
| | - Ying Chen
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
| | - Weidong Rao
- Key Laboratory of Biomass-based Green Fuels and Chemicals, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Shu-Su Shen
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, No. 99, Xuefu road, Huqiu district, Suzhou, 215009, P. R. China
| | - Shun-Yi Wang
- Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu, 215123, China
| |
Collapse
|
5
|
Reimers JR, Yang J, Darwish N, Kosov DS. Silicon - single molecule - silicon circuits. Chem Sci 2021; 12:15870-15881. [PMID: 35024111 PMCID: PMC8672724 DOI: 10.1039/d1sc04943g] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/28/2021] [Indexed: 12/23/2022] Open
Abstract
In 2020, silicon - molecule - silicon junctions were fabricated and shown to be on average one third as conductive as traditional junctions made using gold electrodes, but in some instances to be even more conductive, and significantly 3 times more extendable and 5 times more mechanically stable. Herein, calculations are performed of single-molecule junction structure and conductivity pertaining to blinking and scanning-tunnelling-microscopy (STM) break junction (STMBJ) experiments performed using chemisorbed 1,6-hexanedithiol linkers. Some strikingly different characteristics are found compared to analogous junctions formed using the metals which, to date, have dominated the field of molecular electronics. In the STMBJ experiment, following retraction of the STM tip after collision with the substrate, unterminated silicon surface dangling bonds are predicted to remain after reaction of the fresh tips with the dithiol solute. These dangling bonds occupy the silicon band gap and are predicted to facilitate extraordinary single-molecule conductivity. Enhanced junction extendibility is attributed to junction flexibility and the translation of adsorbed molecules between silicon dangling bonds. The calculations investigate a range of junction atomic-structural models using density-functional-theory (DFT) calculations of structure, often explored at 300 K using molecular dynamics (MD) simulations. These are aided by DFT calculations of barriers for passivation reactions of the dangling bonds. Thermally averaged conductivities are then evaluated using non-equilibrium Green's function (NEGF) methods. Countless applications through electronics, nanotechnology, photonics, and sensing are envisaged for this technology.
Collapse
Affiliation(s)
- Jeffrey R Reimers
- International Centre for Quantum and Molecular Structures and School of Physics, Shanghai University Shanghai 200444 China
- School of Mathematical and Physical Sciences, University of Technology Sydney NSW 2007 Australia
| | - Junhao Yang
- International Centre for Quantum and Molecular Structures and School of Physics, Shanghai University Shanghai 200444 China
| | - Nadim Darwish
- School of Molecular and Life Sciences, Curtin Institute of Functional Molecules and Interfaces, Curtin University Bentley WA 6102 Australia
| | - Daniel S Kosov
- College of Science and Engineering, James Cook University Townsville QLD 4811 Australia
| |
Collapse
|
6
|
Marri I, Amato M, Bertocchi M, Ferretti A, Varsano D, Ossicini S. Surface chemistry effects on work function, ionization potential and electronic affinity of Si(100), Ge(100) surfaces and SiGe heterostructures. Phys Chem Chem Phys 2020; 22:25593-25605. [PMID: 33164017 DOI: 10.1039/d0cp04013d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We combine density functional theory and many body perturbation theory to investigate the electronic properties of Si(100) and Ge(100) surfaces terminated with halogen atoms (-I, -Br, -Cl, -F) and other chemical functionalizations (-H, -OH, -CH3) addressing the absolute values of their work function, electronic affinity and ionization potential. Our results point out that electronic properties of functionalized surfaces strongly depend on the chemisorbed species and much less on the surface crystal orientation. The presence of halogens at the surface always leads to an increment of the work function, ionization potential and electronic affinity with respect to fully hydrogenated surfaces. On the contrary, the presence of polar -OH and -CH3 groups at the surface leads to a reduction of the aforementioned quantities with respect to the H-terminated system. Starting from the work functions calculated for the Si and Ge passivated surfaces, we apply a simple model to estimate the properties of functionalized SiGe surfaces. The possibility of modulating the work function by changing the chemisorbed species and composition is predicted. The effects induced by different terminations on the band energy line-up profile of SiGe surfaces are then analyzed. Interestingly, our calculations predict a type-II band offset for the H-terminated systems and a type-I band offset for the other cases.
Collapse
Affiliation(s)
- Ivan Marri
- Department of Sciences and Methods for Engineering, University of Modena e Reggio Emilia, 42122 Reggio Emilia, Italy.
| | | | | | | | | | | |
Collapse
|
7
|
Peiris CR, Ciampi S, Dief EM, Zhang J, Canfield PJ, Le Brun AP, Kosov DS, Reimers JR, Darwish N. Spontaneous S-Si bonding of alkanethiols to Si(111)-H: towards Si-molecule-Si circuits. Chem Sci 2020; 11:5246-5256. [PMID: 34122981 PMCID: PMC8159313 DOI: 10.1039/d0sc01073a] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We report the synthesis of covalently linked self-assembled monolayers (SAMs) on silicon surfaces, using mild conditions, in a way that is compatible with silicon-electronics fabrication technologies. In molecular electronics, SAMs of functional molecules tethered to gold via sulfur linkages dominate, but these devices are not robust in design and not amenable to scalable manufacture. Whereas covalent bonding to silicon has long been recognized as an attractive alternative, only formation processes involving high temperature and/or pressure, strong chemicals, or irradiation are known. To make molecular devices on silicon under mild conditions with properties reminiscent of Au–S ones, we exploit the susceptibility of thiols to oxidation by dissolved O2, initiating free-radical polymerization mechanisms without causing oxidative damage to the surface. Without thiols present, dissolved O2 would normally oxidize the silicon and hence reaction conditions such as these have been strenuously avoided in the past. The surface coverage on Si(111)–H is measured to be very high, 75% of a full monolayer, with density-functional theory calculations used to profile spontaneous reaction mechanisms. The impact of the Si–S chemistry in single-molecule electronics is demonstrated using STM-junction approaches by forming Si–hexanedithiol–Si junctions. Si–S contacts result in single-molecule wires that are mechanically stable, with an average lifetime at room temperature of 2.7 s, which is five folds higher than that reported for conventional molecular junctions formed between gold electrodes. The enhanced “ON” lifetime of this single-molecule circuit enables previously inaccessible electrical measurements on single molecules. Spontaneously formed Si–S bonds enable monolayer and single-molecule Si–molecule–Si circuits.![]()
Collapse
Affiliation(s)
- Chandramalika R Peiris
- School of Molecular and Life Sciences, Curtin Institute of Functional Molecules and Interfaces, Curtin University Bentley WA 6102 Australia
| | - Simone Ciampi
- School of Molecular and Life Sciences, Curtin Institute of Functional Molecules and Interfaces, Curtin University Bentley WA 6102 Australia
| | - Essam M Dief
- School of Molecular and Life Sciences, Curtin Institute of Functional Molecules and Interfaces, Curtin University Bentley WA 6102 Australia
| | - Jinyang Zhang
- School of Molecular and Life Sciences, Curtin Institute of Functional Molecules and Interfaces, Curtin University Bentley WA 6102 Australia
| | - Peter J Canfield
- International Centre for Quantum and Molecular Structures, School of Physics, Shanghai University Shanghai 200444 China.,School of Chemistry, The University of Sydney NSW 2006 Australia
| | - Anton P Le Brun
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization (ANSTO) Lucas Heights NSW 2234 Australia
| | - Daniel S Kosov
- College of Science and Engineering, James Cook University Townsville QLD 4811 Australia
| | - Jeffrey R Reimers
- International Centre for Quantum and Molecular Structures, School of Physics, Shanghai University Shanghai 200444 China.,School of Mathematical and Physical Sciences, University of Technology Sydney NSW 2007 Australia
| | - Nadim Darwish
- School of Molecular and Life Sciences, Curtin Institute of Functional Molecules and Interfaces, Curtin University Bentley WA 6102 Australia
| |
Collapse
|
8
|
Yang N, Li W, Dong L. Modification of a H-terminated silicon surface by organic sulfide molecules: the mechanism and origin of reactivity. NEW J CHEM 2020. [DOI: 10.1039/c9nj06115k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
For the reactions of disulfide molecules (RSSR), the steric effect rather than the electronic effect of the R group is the main origin of the different reactivity. In the reactions of sulfide molecules (RSXR′, X = S, P, Si, O, N, C), charges on the S atom and dissociation energies of the S–X bonds have a great impact on the reactivity of these reactions.
Collapse
Affiliation(s)
- Na Yang
- Institute of Nuclear Physics and Chemistry
- China Academy of Engineering Physics
- Mianyang
- P. R. China
| | - Weiyi Li
- School of Science, Xihua University
- Chengdu
- P. R. China
| | - Liang Dong
- Institute of Nuclear Physics and Chemistry
- China Academy of Engineering Physics
- Mianyang
- P. R. China
| |
Collapse
|
9
|
Soliman AIA, Utsunomiya T, Ichii T, Sugimura H. 1,2-Epoxyalkane: Another Precursor for Fabricating Alkoxy Self-Assembled Monolayers on Hydrogen-Terminated Si(111). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:13162-13170. [PMID: 30299104 DOI: 10.1021/acs.langmuir.8b02717] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This work describes the UV alkoxylation of a series of 1,2-epoxyalkanes on the hydrogen-terminated silicon (H-Si) substrate. The formation of alkoxy self-assembled monolayers (SAMs) and the nature of bonding at the surface of H-Si were examined using water contact angle goniometer, spectroscopic ellipsometer, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy. UV exposure to 1,2-epoxyalkane mesitylene solution for 60 min formed alkoxy-SAMs onto H-Si with hydrophobic properties. The local molecular environment of the alkyl chains transitioned from a disordered, liquid-like state to an ordered, crystalline-like structure with increasing the chain length. XPS and FTIR indicated that the reaction of H-Si with 1,2-epoxyalkane produced Si-O-C linkages. The Si-H bond homolysis and electron/hole were the plausible mechanistic routes for the grafting of 1,2-epoxyalkanes.
Collapse
Affiliation(s)
- Ahmed I A Soliman
- Department of Materials Science and Engineering , Kyoto University , Yoshida-Hommachi , Sakyo-ku, Kyoto 606-8501 , Japan
- Chemistry Department, Faculty of Science , Assiut University , Assiut 71516 , Egypt
| | - Toru Utsunomiya
- Department of Materials Science and Engineering , Kyoto University , Yoshida-Hommachi , Sakyo-ku, Kyoto 606-8501 , Japan
| | - Takashi Ichii
- Department of Materials Science and Engineering , Kyoto University , Yoshida-Hommachi , Sakyo-ku, Kyoto 606-8501 , Japan
| | - Hiroyuki Sugimura
- Department of Materials Science and Engineering , Kyoto University , Yoshida-Hommachi , Sakyo-ku, Kyoto 606-8501 , Japan
| |
Collapse
|
10
|
Chatgilialoglu C, Ferreri C, Landais Y, Timokhin VI. Thirty Years of (TMS)3SiH: A Milestone in Radical-Based Synthetic Chemistry. Chem Rev 2018; 118:6516-6572. [DOI: 10.1021/acs.chemrev.8b00109] [Citation(s) in RCA: 138] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
| | - Carla Ferreri
- ISOF, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, 40129 Bologna, Italy
| | - Yannick Landais
- University of Bordeaux, Institute of Molecular Sciences, UMR-CNRS 5255, 351 cours de la libération, 33405 Talence Cedex, France
| | - Vitaliy I. Timokhin
- Department of Biochemistry, University of Wisconsin-Madison, 1552 University Avenue, Madison, Wisconsin 53726, United States
| |
Collapse
|
11
|
Iyer A, Kearney K, Wakayama S, Odoi H, Ertekin E. Design Strategy for the Molecular Functionalization of Semiconductor Photoelectrodes: A Case Study of p-Si(111) Photocathodes for H 2 Generation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:2959-2966. [PMID: 29412684 DOI: 10.1021/acs.langmuir.7b03948] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Functionalization of semiconductor photoelectrodes is actively pursued as an approach to improve the efficiency of photoelectrochemical reactions by modulating the semiconductor's barrier height, but the selection of molecules for functionalization remains largely empirical. We propose a simple but effective design strategy for the organic functionalization of photocathodes for high-efficiency hydrogen generation based on first-principles density functional theory (DFT) calculations. The surface dipole of the functionalized photocathode determines its barrier height, which can be optimized to enhance charge separation at the semiconductor-electrolyte interface. Focusing on p-Si(111) photocathodes functionalized with different mixed aryl/methyl monolayers, we use DFT to systematically investigate the effect of - the presence and distribution of pi bonds, binding atom (the atom in the functional group that bonds with the Si surface), functional group length, and electrophilic substituent groups - on the surface dipole and charge rearrangement at the functionalized surface. We find that the most important factors affecting the surface dipole are the intrinsic molecular dipole moment of the organic moiety, the presence of electrophilic substituent groups, and the binding atom. Using these findings, a three-step design strategy is proposed for the experimental realization of high-performing functionalized p-Si(111) photocathodes by maximizing the surface dipole.
Collapse
Affiliation(s)
- Ashwathi Iyer
- Department of Physics , University of Illinois , 1110 W Green Street , Urbana , Illinois 61801 , United States
- International Institute for Carbon Neutral Energy Research (WPI-I2CNER) , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Kara Kearney
- Department of Mechanical Science and Engineering , University of Illinois , 1204 West Green Street , Urbana , Illinois 61801 , United States
- International Institute for Carbon Neutral Energy Research (WPI-I2CNER) , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Shohei Wakayama
- Department of Mechanical and Aerospace Engineering , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Hirotoshi Odoi
- Department of Mechanical and Aerospace Engineering , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Elif Ertekin
- Department of Mechanical Science and Engineering , University of Illinois , 1204 West Green Street , Urbana , Illinois 61801 , United States
- International Institute for Carbon Neutral Energy Research (WPI-I2CNER) , Kyushu University , 744 Moto-oka , Nishi-ku, Fukuoka 819-0395 , Japan
| |
Collapse
|
12
|
Marinins A, Zandi Shafagh R, van der Wijngaart W, Haraldsson T, Linnros J, Veinot JGC, Popov S, Sychugov I. Light-Converting Polymer/Si Nanocrystal Composites with Stable 60-70% Quantum Efficiency and Their Glass Laminates. ACS APPLIED MATERIALS & INTERFACES 2017; 9:30267-30272. [PMID: 28853276 DOI: 10.1021/acsami.7b09265] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Thiol-ene polymer/Si nanocrystal bulk hybrids were synthesized from alkyl-passivated Si nanocrystal (Si NC) toluene solutions. Radicals in the polymer provided a copassivation of "dark" Si NCs, making them optically active and leading to a substantial ensemble quantum yield increase. Optical stability over several months was confirmed. The presented materials exhibit the highest photoluminescence quantum yield (∼65%) of any solid-state Si NC hybrid reported to date. The broad tunability of thiol-ene polymer reactivity provides facile glass integration, as demonstrated by a laminated structure. This, together with extremely fast polymerization, makes the demonstrated hybrid material a promising candidate for light converting applications.
Collapse
Affiliation(s)
- Aleksandrs Marinins
- Department of Applied Physics, KTH - Royal Institute of Technology , 16440 Stockholm, Sweden
| | - Reza Zandi Shafagh
- Department of Micro and Nanosystems, KTH - Royal Institute of Technology , 10044 Stockholm, Sweden
| | - Wouter van der Wijngaart
- Department of Micro and Nanosystems, KTH - Royal Institute of Technology , 10044 Stockholm, Sweden
| | - Tommy Haraldsson
- Department of Micro and Nanosystems, KTH - Royal Institute of Technology , 10044 Stockholm, Sweden
| | - Jan Linnros
- Department of Applied Physics, KTH - Royal Institute of Technology , 16440 Stockholm, Sweden
| | - Jonathan G C Veinot
- Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada
| | - Sergei Popov
- Department of Applied Physics, KTH - Royal Institute of Technology , 16440 Stockholm, Sweden
| | - Ilya Sychugov
- Department of Applied Physics, KTH - Royal Institute of Technology , 16440 Stockholm, Sweden
| |
Collapse
|
13
|
Escorihuela J, Zuilhof H. Rapid Surface Functionalization of Hydrogen-Terminated Silicon by Alkyl Silanols. J Am Chem Soc 2017; 139:5870-5876. [PMID: 28409624 PMCID: PMC5419668 DOI: 10.1021/jacs.7b01106] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
![]()
Surface
functionalization of inorganic semiconductor substrates,
particularly silicon, has focused attention toward many technologically
important applications, involving photovoltaic energy, biosensing
and catalysis. For such modification processes, oxide-free (H-terminated)
silicon surfaces are highly required, and different chemical approaches
have been described in the past decades. However, their reactivity
is often poor, requiring long reaction times (2–18 h) or the
use of UV light (10–30 min). Here, we report a simple and rapid
surface functionalization for H-terminated Si(111) surfaces using
alkyl silanols. This catalyst-free surface reaction is fast (15 min
at room temperature) and can be accelerated with UV light irradiation,
reducing the reaction time to 1–2 min. This grafting procedure
leads to densely packed organic monolayers that are hydrolytically
stable (even up to 30 days at pH 3 or 11) and can display excellent
antifouling behavior against a range of organic polymers.
Collapse
Affiliation(s)
- Jorge Escorihuela
- Laboratory of Organic Chemistry, Wageningen University and Research , Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Han Zuilhof
- Laboratory of Organic Chemistry, Wageningen University and Research , Stippeneng 4, 6708 WE Wageningen, The Netherlands.,School of Pharmaceutical Sciences and Technology, Tianjin University , Tianjin 300072, China.,Department of Chemical and Materials Engineering, King Abdulaziz University , Jeddah 23218, Saudi Arabia
| |
Collapse
|
14
|
Vilan A, Cahen D. Chemical Modification of Semiconductor Surfaces for Molecular Electronics. Chem Rev 2017; 117:4624-4666. [PMID: 28230354 DOI: 10.1021/acs.chemrev.6b00746] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Inserting molecular monolayers within metal/semiconductor interfaces provides one of the most powerful expressions of how minute chemical modifications can affect electronic devices. This topic also has direct importance for technology as it can help improve the efficiency of a variety of electronic devices such as solar cells, LEDs, sensors, and possible future bioelectronic ones. The review covers the main aspects of using chemistry to control the various aspects of interface electrostatics, such as passivation of interface states and alignment of energy levels by intrinsic molecular polarization, as well as charge rearrangement with the adjacent metal and semiconducting contacts. One of the greatest merits of molecular monolayers is their capability to form excellent thin dielectrics, yielding rich and unique current-voltage characteristics for transport across metal/molecular monolayer/semiconductor interfaces. We explain the interplay between the monolayer as tunneling barrier on the one hand, and the electrostatic barrier within the semiconductor, due to its space-charge region, on the other hand, as well as how different monolayer chemistries control each of these barriers. Practical tools to experimentally identify these two barriers and distinguish between them are given, followed by a short look to the future. This review is accompanied by another one, concerning the formation of large-area molecular junctions and charge transport that is dominated solely by molecules.
Collapse
Affiliation(s)
- Ayelet Vilan
- Department of Materials & Interfaces, Weizmann Institute of Science , Rehovot, Israel 76100
| | - David Cahen
- Department of Materials & Interfaces, Weizmann Institute of Science , Rehovot, Israel 76100
| |
Collapse
|