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MAY 5-6
10+10 WORKSHOP ON SUSTAINABLE CHEMISTRY
COLLEGE OF LETTERS AND SCIENCE DEPARTMENT OF CHEMISTRY UC DAVIS
8:00 AM – 3:00 PM 172 Chemistry
Please join us for exciting talks in inorganic, theoretical, organic, and biological chemistry, given by experts from the Departments of Chemistry at Peking University and UC Davis. Presentations are open to graduate and undergraduate students. Seating is limited and available on a first-come, first-served basis.
Hosted by Frank Osterloh & Lingdong Sun
For program details, see web link and posting outside 172 Chemistry.
http://chemgroups.ucdavis.edu/~liu/10+10/Workshop%202016%20Lead%20Page.html
Torres del Paine National Park, Chile THURSDAY & FRIDAY
SPONSORED BY
MATH & PHYSICAL SCIENCES
Thursday, May 5, 2016
8:00 Refreshments & Opening Remarks: Dean Navrotsky, Profs. Sun and Osterloh, co-chairs Sustainable Chemistry Session 1, Chair: Frank Osterloh 8:20 Song Gao, PKU CCME
ORGANOMETALLIC SINGLE-ION MAGNETS 8:45 Carlito Lebrilla, UCD
WHAT CAN ADVANCED ANALYTICAL TOOLS TELL US ABOUT BREAST FEEDING? 9:10 Chunhu Yan, PKU CCME
SYNTHESIS AND CATALYTIC BEHAVIOUR OF ANISOTROPIC CERIA NANOMATERIALS 9:35 Mark Mascal, UCD
CONVERSION OF BIOMASS INTO 5-(CHLOROMETHYL)FURFURAL (CMF): A NEW PLATFORM MOLECULE FOR THE SYNTHESIS OF RENEWABLE SUBSTITUTES FOR PETROLEUM PRODUCTS
10:00 Coffee Break and Discussion Sustainable Chemistry Session 2, Chair: Gang Sun 10:30 Lingdong Sun, PKU CCME
NEW INSIGHTS INTO LUMINESCENCE OF RARE EARTH NANOCRYSTALS 10:55 Allen Doyle, UCD
GREEN LABS: ENERGY CONSERVATION AND RECYCLING IN CHEMISTRY LABORATORIES
11:20 Kai Wu, PKU CCME PLAY WITH MOLECULES AT SURFACES
11:45 Discussion 12:00 Lunch Sustainable Chemistry Session 3, Chair: Alan Balch 13:30 Shota Atsumi, UCD
SYSTEMATIC CONSTRUCTION OF BIOSYNTHETIC PATHWAYS FOR CHEMICAL PRODUCTION
13:55 Wenbin Zhang, PKU CCME CELLULAR SYNTHESIS OF PROTEIN CATENANES AND OTHER COMPLEX TOPOLOGIES
14:20 Annaliese Franz, UCD DESIGN AND SYNTHESIS OF ORGANIC SILANOLS AND DISILOXANEDIOLS AS CATALYSTS FOR SUSTAINABLE CHEMISTRY
14:45 Discussion 15:00 Excursion 17:00 Break 18:00 Dinner
Friday, May 6, 2016
8:00 Refreshments & General Announcements Sustainable Chemistry Session 4, Chair: Wenbin Zhang 8:20 Jian Pei, PKU CCME
FINE TUNING OF CRYSTAL PACKING AND CHARGE TRANSPORT PROPERTIES OF BDOPV DERIVATIVES THROUGH FLUORINE SUBSTITUTION
8:45 Kirill Kovnir, UCD RATIONAL APPROACHES FOR NOVEL THERMOELECTRIC MATERIALS
9:10 Yi Qin Gao, PKU CCME QM/MM STUDIES OF CHEMICAL REACTIONS IN SOLUTION, A REACTION COORDINATE-FREE APPROACH
9:35 Davide Donadio, UCD OPTIMIZATION OF FLEXIBLE THERMOELECTRIC MATERIALS: FROM SILICON NANOSTRUCTURES TO MOLECULAR JUNCTIONS
10:00 Coffee Break and Discussion Sustainable Chemistry Session 5, Chair: Philip Power 10:30 Ding Ma, PKU CCME
INSIGHT INTO IRON-BASED FISCHER-TROPSCH SYNTHESIS REACTION 10:55 Louise Berben, UCD
MAKING C-H BONDS WITH CO2: TUNING MOLECULAR IRON CATALYSTS WITH LIGAND DESIGN
11:20 Junliang Sun, PKU CCME STRUCTURE CHARACTERIZATION COMBINING XRD AND EM
11:45 Discussion 12:00 Group Photo 12:15 Lunch Sustainable Chemistry Session 6, Chair: TBA 13:45 Lee-Ping Wang, UCD
MOLECULAR-SCALE INVESTIGATION OF WATER DESALINATION USING POLARIZABLE MOLECULAR DYNAMICS SIMULATIONS
14:10 Frank Osterloh, UCD INORGANIC NANOMATERIALS FOR ARTIFICIAL PHOTOSYNTHESIS
14:35 Discussion and Closing Comments 15:00 Excursion 17:00 Break 18:00 Dinner
SYSTEMATIC CONSTRUCTION OF BIOSYNTHETIC PATHWAYS FOR CHEMICAL PRODUCTION Shota Atsumi
Whole-cell biocatalysts have gained increased interest as a method for
producing chemicals and fuels renewably due to concerns over future fossil
fuel supplies and environmental impacts. Using an intact microorganism as
a catalyst offers several advantages over conventional synthesis: 1. high
enantioselectivity, 2. high regioselectivity, 3. self-replicating, 4. self-
maintaining, and 5. high multistep efficiency from a renewable carbon source. We engineered
Escherichia coli to expand natural metabolism and produce several target chemicals specifically and
efficiently through systematic comparison of components in each step of the biosynthetic pathway and
careful matching of genes, pathway, and chemical toxicity to the chosen host. We expanded this
strategy to cyanobacteria. Cyanobacteria offer advantages to microbial chemical production from CO2,
including use of non-arable land, high-efficiency photon harvesting, and direct conversion of CO2
without a biomass intermediate.
MAKING C-H BONDS WITH CO2: TUNING MOLECULAR IRON
CATALYSTS WITH LIGAND DESIGN
Atefeh Taheri, Natalia D. Loewen, Emily J. Thompson, James C. Fettinger,
Louise A. Berben
OPTIMIZATION OF FLEXIBLE THERMOELECTRIC MATERIALS: FROM
SILICON NANOSTRUCTURES TO MOLECULAR JUNCTIONS
Claudia Mangold, Qian Li, Shiyun Xiong, Daniele Selli, Ivan Duchemin,
Sanghamitra Neogi, Gemma Solomon, Davide Donadio
The thermoelectric effect, which converts temperature gradients into
electrical power, would be a valuable renewable energy resource, allowing
recovery of waste heat from traditional energy conversion processes. Yet,
low performance and cost of materials limit TE conversion to niche application.
By molecular simulations, we identify new strategies based on nanoscale engineering to achieve
technologically Piviable thermoelectric performance in inexpensive and flexible materials mostly
composed of carbon and silicon. Our calculations demonstrate that surface engineering of ultra-thin
silicon membranes and molecular design of all-carbon junctions lead to improvements of the
thermoelectric figure of merit over two orders of magnitude in both classes of systems.
GREEN LABS: ENERGY CONSERVATION AND RECYCLING IN
CHEMISTRY LABORATORIES
Allen Doyle, MS Chemical Oceanography
DESIGN AND SYNTHESIS OF ORGANIC SILANOLS AND
DISILOXANEDIOLS AS CATALSYTS FOR SUSTAINABLE CHEMISTRY
Kayla Diemoz, Austin Kelly, Kelsey Mesa, Ngon Tran, Sean Wilson,
Annaliese Franz*
The incorporation of silanol and silanediol groups into organic scaffolds
provides the opportunity to develop new activating groups for small
molecule catalysts based on sustainable materials. We have designed and
synthesized new organosilicon molecules incorporating silanol, silanediol and disiloxanediol groups to
study their catalytic activity, molecular recognition and hydrogen-bonding properties. We have
demonstrated unique examples of cooperative hydrogen-bonding effects of silanediols, the enhanced
catalytic activity of disiloxanediols relative to other silanols, and the role of silanols for bifunctional
catalysis. Applications of new silicon-containing organocatalysts for carbon-carbon bond-forming
reactions and enantioselective synthesis will be presented. Structural studies, reaction progress
kinetics, and various NMR binding studies will be presented for mechanistic and molecular insights for
catalyst activity and design.
ORGANOMETALLIC SINGLE-ION MAGNETS
Song Gao
Beijing National Laboratory for Molecular Sciences, State Key Laboratory of
Rare Earth Materials Chemistry and Applications, College of Chemistry and
Molecular Engineering, Peking University, Beijing 100871, China.
After the milestone discovery of the first single-molecule magnets (SMMs)
Mn12ac, many new SMMs were structurally and magnetically characterized. The most studied systems
are mainly conventional coordination compounds with polynuclear structures. From 2011, we explored a
series mononuclear organometallic sandwich molecules, Cp*LnCOT (Cp* = C5Me5-,
pentamethylcyclopenta-dienide; COT = C8H82-, cyclooctatetraenide; Ln = Dy3+, Ho3+, Er3+), which behave
as a single-ion magnets (SIMs) [1-4]. It opened a door of SMMs to the chemists in organometallic
chemistry. Recently, we found that some new sandwich and half-sandwich lanthanide organometallic
molecules could also show the slow relaxation of magnetization [5-8]. Moreover, a few new linear two-
coordinated Co(I)/Co(II) organometallic SIM were discovered [9-10]. We hope these systems can provide
new understandings of slow magnetic relaxation and new clues on the design and synthesis of
molecular nanomagnets.
[1] S.-D. Jiang, B.-W. Wang, H.-L. Sun, Z.-M. Wang, S. Gao, J. Am. Chem. Soc., 2011, 133, 4730.
[2] S.-D. Jiang, S.-S. Liu, L.-N. Zhou, B.-W. Wang, Z.-M. Wang, S. Gao, Inorg. Chem., 2012, 51, 3079.
[3] M.-E. Boulon, G. Cucinotta, S.-S. Liu, S.-D. Jiang, L. Ungur, L. F.Chibotaru, Gao, S. R. Sessoli, Chem. Eur. J., 2013, 19, 13726.
[4] M. Perfetti, G. Cucinotta, M.-E. Boulon, F. E. Hallak, S. Gao, R. Sessoli, Chem. Eur. J., 2014, 20, 14051.
[5] S.-S. Liu, J.W. Ziller, Y.-Q. Zhang, B.-W. Wang, W.J. Evans, S. Gao, Chem. Commun., 2014, 11418.
[6] S.-S. Liu; L. Xu, S.-D. Jiang, Y.-Q. Zhang, Y.-S. Meng, Z.-T. Wang, B.-W. Wang, W.-X. Zhang, Z.-F. Xi, S. Gao, Inorg. Chem.,
2015, 54, 5162.
[7] Y.-S. Meng, Y.-S. Qiao, Y.-Q. Zhang, S.-D. Jiang, Z.-S. Meng, B.-W. Wang, Z.-M. Wang, S. Gao, Chem. Eur. J., 2016, DOI:
10.1002/chem.201600023
[8] Y.-S. Meng, C.-H. Wang, Y.-Q. Zhang, X.-B. Leng, B.-W. Wang, Y.-F. Chen, S. Gao, Inorg. Chem. Front., 2016, DOI:
10.1039/C6QI00028B
[9] Y.-S. Meng, Z.-B. Mo, B.-W. Wang, Y.-Q. Zhang, L. Deng, S. Gao, Chem. Sci., 2015, 6, 7156.
[10] X.-N.Yao, J.-Z. Du, Y.-Q. Zhang, X.-B. Leng, M.-W. Yan, S.-D. Jiang, Z.-X. Wang, Z.-W. Ouyang, L. Deng, B.-W. Wang, S.
Gao, submitted.
QM/MM STUDIES OF CHEMICAL REACTIONS IN SOLUTION, A
REACTION COORDINATE-FREE APPROACH
Yi Qin Gao
College of Chemistry and Molecular Engineering, Peking University
Many chemical reactions occur in solutions and it is desirable to understand
how solvation affects their mechanisms. Theoretical studies for these
reactions are normally hindered by the complex energy landscapes of molecular systems. Molecular
mechanistic studies are very commonly performed with a pre-defined reaction coordinate. In this talk,
we will discuss how one enhanced sampling technique, integrated tempering sampling (ITS), can be
used to improve the efficiency of molecular dynamics simulations in searching for molecular
configurations. We then illustrate how trajectory sampling techniques can be combined with ITS to
obtain kinetic information for systems with high energy barriers. These enhanced sampling methods
were applied in QM/MM simulations and allowed us to gain molecular details on how solvation and
substituents affect the chemical reactions in solution. Using this approach we were able to calculate the
rate constants truly reaction-coordinate-free. The calculated reaction rates are in good agreement with
experiments.
RATIONAL APPROACHES FOR NOVEL THERMOELECTRIC MATERIALS
Kirill Kovnir
The phenomenon of thermoelectricity is attributed to the interconversion of
thermal and electrical forms of energy. We developed a new class of bulk
thermoelectric materials based on clathrates with a three dimensional
framework comprised of oversized transition metal-phosphorus polyhedral
cages that encapsulate guest cations. Transition metal-based clathrates have
the following advantages over conventional Si-, Ge-, and Sn-based clathrates: i) a larger variety of
framework topologies; ii) a higher tunability of the electronic properties via framework substitutions. The
correlation between the crystal structure, distribution of the metal and phosphorus atoms over the
clathrate framework and thermoelectric properties will be discussed.
WHAT CAN ADVANCED ANALYTICAL TOOLS TELL US ABOUT BREAST
FEEDING?
Carlito B. Lebrilla
INSIGHT INTO IRON-BASED FISCHER-TROPSCH SYNTHESIS
REACTION
Ding Ma
Beijing National Laboratory for Molecular Sciences, College of Chemistry and
Molecular Engineering, Peking University, Beijing 100871, China
As one of the oldest and most complicated heterogeneous catalytic reaction,
the basic understand regarding the Fischer-Tropsch synthesis (FTS) in term of the catalyst active phase
and reaction mechanism remain unclear and even in debates. In this report, pure phase iron-based
catalysts including α-Fe, Fe5C2, Fe7C3 and Fe2C were prepared and used to identify their intrinsic activity.
It was found that Fe5C2 is the most active catalyst while α-Fe underwent a gradual increase in activity in
the induction period due to the structural transformation toward iron carbide. A transient experiment
named high-pressure stepwise temperature programming surface reaction (STPSR), in-situ XRD and X-
ray absorption fine structure (XAFS) experiments were conducted to follow the reaction dynamics over
these catalysts and structural evolution under FTS condition. Coping with comprehensive density
functional theory calculations, a vivid image about how the FTS processes are for the first time
disclosed. It was found that though α-Fe was highly active for CO activation, the too strong binding with
dissociated atomic carbon prevented subsequent C-C coupling and methanation. α-Fe catalyst, whose
intrinsic activity for FTS was therefore rather low, tends to be carburized and transformed into
thermodynamically more favorable iron carbide under FTS condition. For iron carbide, CO activation
remained facile, but dissociated atomic carbon was largely destabilized. This facilitated greatly the
formation of monomers and C-C coupling with preference of unsaturated hydrocarbon. Importantly, the
effective barrier for C-C coupling was even lower than that of CO activation. The insights revealed are
valuable for rationale of design for iron-based FTS catalysts.
CONVERSION OF BIOMASS INTO 5-(CHLOROMETHYL)FURFURAL
(CMF): A NEW PLATFORM MOLECULE FOR THE SYNTHESIS OF
RENEWABLE SUBSTITUTES FOR PETROLEUM PRODUCTS
Mark Mascal
INORGANIC NANOMATERIALS FOR ARTIFICIAL PHOTOSYNTHESIS
Frank E. Osterloh
The identification of an artificial photosynthesis method to turn solar energy
into globally usable amounts of fuel is considered one of the most important
challenges today. Photochemical water splitting with particle-based systems
has the greatest potential to achieve this goal. Because of the total
integration of components for light absorption and water electrolysis,
particle-based photocatalysts (see Figure below) can be over one order of
magnitude cheaper than photoelectrochemical or photovoltaic cells. Currently, the development of such
systems is limited by intrinsic materials issues and by an incomplete understanding of the reactions of
photochemical charge carriers at irregular interfaces. This talk will discuss these obstacles and present
ways to overcome them using recent examples from the literature and from the author’s own laboratory.
FINE TUNING OF CRYSTAL PACKING AND CHARGE TRANSPORT
PROPERTIES OF BDOPV DERIVATIVES THROUGH FLUORINE
SUBSTITUTION
Jin-Hu Dou, Jie-Yu Wang, and Jian Pei*
Beijing National Laboratory for Molecular Sciences (BNLMS), the Key
Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of
Education, Center of Soft Matter Science and Engineering, College of
Chemistry and Molecular Engineering, Peking University, Beijng 100871, China.
Molecular packing in organic materials greatly influences the electronic coupling and therefore charge
transport process in organic light-emitting diodes (OLED), organic photovoltaics (OPV) and organic field-
effect transistors (OFET). Charge transport in molecular level is mainly determined by two factors,
electronic coupling and reorganization energy. The electronic coupling (absolute of transfer integral) is
strongly dependent on the molecular packing mode. To obtain large transfer integral, short π-π stacking
distance and optimal displacements are desired.
Herein, we have realized systematically fine tuning of the single-crystal molecular packing of five
benzodifurandione-based oligo(p-phenylene vinylene) (BDOPV)-based small molecules through
incorporation of electronegative fluorine atoms on the backbone. While these molecules all exhibit
similar column stacking configurations in their single crystals, the intermolecular displacements and
distances are substantially modified by tuning the amounts and/or the positions of the substituent
fluorine atoms. The electronic couplings for electron transfer can vary from 71 meV in a slipped stack to
201 meV in a nearly cofacial antiparallel stack, leading to the electron mobility of the BDOPV derivatives
increasing from 2.6 to 12.6 cm2 V−1 s−1. The electron mobility of five molecules did not show good
correlation with LUMO levels, indicating that the distinct difference of charge transport properties is
resulted from molecular packing. Our work not only provides a series of high electron mobility organic
semiconductors, but also demonstrates that fluorination is an effective approach to finely tune single-
crystal packing modes beyond simply lowering molecular energy levels.
[1] J.-H. Dou, Y.-Q. Zheng, Z.-F. Yao, Z.-A. Yu, T. Lei, X. Shen , X.-Y. Luo, J. Sun, S.-D. Zhang , Y.-F. Ding, G. Han, Y. Yi, J.-Y.
Wang, J. Pei , J. Am. Chem. Soc., 2015, 137, 15947.
[2] J.-H Dou, Y.-Q. Zheng, Z.-F. Yao, T. Lei, X. Shen, X.-Y. Luo, Z.-A. Yu, S.-D. Zhang, G. Han, Z. Wang, Y. Yi, J.-Y. Wang, J. Pei,
Adv. Mater. 2015, 27, 8015.
STRUCTURE CHARACTERIZATION COMBINING XRD AND EM
Junliang Sun
Beijing National Laboratory for Molecular Sciences, State Key Laboratory of
Rare Earth Materials Chemistry and Applications, College of Chemistry and
Molecular Engineering, Peking University, Beijing, 100871, China
Structure determination of nano-size crystals or crystals with defects is always a challenging problem.
For quite lots of materials, it is very difficult to synthesize large/good enough crystals for single crystal X-
ray diffraction studies. Powder X-ray diffraction (PXRD) is the major method for their atomic structure
determination, PXRD is a quite mature technique and lots of powder structures were solved. However,
for complicated structures with huge unit cell dimensions or those with crystal sizes smaller than 100nm,
it is quite often to have severe peak overlapping problems, which makes it extremely difficult to solve the
structure from PXRD alone. Electrons which interact with matter much stronger than X-ray can produce
single-crystal-like diffraction from nano-crystalline materials, which makes it possible to collect single-
crystal-like diffraction data.
The new technique we developed, Rotation Electron Diffraction, can be used for collecting 3D electron
diffraction data. Compared with traditional electron diffraction methods, this technique gives lower
dynamical effects and much higher data completeness. Using the intensities abstracted from the data,
complicated structures can be directly solved using the similar methods as single-crystal X-ray
diffraction. Combining it with other techniques, such as PXRD or even SXRD, more complicated
structures can be solved.
3D electron diffraction and powder X-ray diffraction
Reference：
[1] Junliang Sun, Charlotte Bonneau, Ángel Cantín, Avelino Corma*, María J. Díaz-Cabañas, Manuel Moliner, Daliang
Zhang, Mingrun Li & Xiaodong Zou* Nature 2009, 458, 1154.
[2] Wei Wan*, Junliang Sun*, Jie Su, Sven Hovmöller, Xiaodong Zou* J. Appl. Cryst. 2013, 46, 1863.
[3] Wei Hua, Hong Chen, Zheng-Bao Yu, Xiaodong Zou, Jianhua Lin*, Junliang Sun* Angew. Chem. Int. Ed. 2014, 53
5868.
[4] Hong Chen, Jing Ju, Qingpeng Meng, Jie Su, Cong Lin, Zhengyang Zhou, Guobao Li, Weilu Wang, Wenliang Gao,
Chunmei Zeng, Chiu Tang, Jianhua Lin*, Tao Yang*, Junliang Sun* J. Am. Chem. Soc. 2015, 137, 7047
[5] Kun Lin, Zhengyang Zhou, Laijun Liu, Hongqiang Ma, Jun Chen, Jinxia Deng, Junliang Sun*, Li You, Hidetaka Kasai,
Kenichi Kato, Masaki Takata, Xianran Xin* J. Am. Chem. Soc. 2015, 137, 13468
NEW INSIGHTS INTO LUMINESCENCE OF RARE EARTH
NANOCRYSTALS
Ling-Dong Sun, Hao Dong, Pei-Zhi Zhang, Yang Li, Shuo Shi, Chun-Hua
Yan
Beijing National Laboratory for Molecular Sciences, State Key Laboratory of
Rare Earth Materials Chemistry and Applications, College of Chemistry and
Molecular Engineering, Peking University, Beijing, 100871, China
Luminescence of rare earth nanocrystals, ranged from ultraviolet to visible and even the near infrared,
are attractive for a broad field of photon conversion applications. Thanks to the abundant energy levels
of rare earth ions, energy transfer between them is important for luminescence. It could be deteriorative
for transitions, and it also could be a bridge for energy flowing.
Nanostructure, which is able to localize the energy transfer in nano-dimension, could be introduced as
an ideal platform to realize selective or combinatorial luminescence for ra re earth. Er3+ or Tm3+ activated
upconversion emission are realized with the energy transfer from Yb3+, and the multiphoton radiation
process are found to be correlated well with not only the excitation density, but also the site symmetry of
rare earth ions.
Nd3+→Yb3+ energy transfer with an efficency higher than 70% were also designed to combine with
upconverting rare earth pairs (Yb3+/Er3+, Tm3+) via a core/shell structure. In a typical nanoparticle,
upconversion emissions form Er3+ or Tm3+ could be sensitized both from Yb3+and Nd3+ excitation.
Furthermore, with the excitation of Nd3+ at 808 nm (4I9/2→4F5/2), downshifting emission from Nd3+ at 1064
nm (4F3/2→4I13/2) and Yb3+ at 970 nm (4F5/2, →4F7/2) could be observed simultaneously. Together with a
higher quantum efficiency, these emitting rare earth nanocrystals could be used as NIR excited and
emitted nanop robes for imaging and detection studies.
[1] Y.F. Wang, G. Y. Liu, L. D. Sun, J. W. Xiao, J. C. Zhou, ACS Nano, 2013, 7, 7200.
[2] H. Dong, L. D. Sun, Y.F. Wang, J. Ke, R. Si, J. W. Xiao, G. M. Lyu, S. Shi, C. H. Yan, J. Am. Chem. Soc., 2015, 137(20), 6569.
[3] L. Wang, H. Dong, Y. Li, R. Liu, Y.F. Wang, H. K. Bisoyi, L. D. Sun, C. H. Yan, and Q. Li, Adv. Mater., 2015, 27(12), 2065.
MOLECULAR-SCALE INVESTIGATION OF WATER DESALINATION USING POLARIZABLE MOLECULAR DYNAMICS SIMULATIONS Yudong Qiu, Lee-Ping Wang
The need to improve the sustainability of water resources is an important
challenge requiring fundamental understanding of water treatment at the
molecular level. In this work, we present some early results of our
investigation into the process of water desalination using nanoporous
graphene at the molecular level. In order to develop the accurate potential
models needed to describe the intermolecular interactions, we have developed new algorithms for
geometry optimization in ab initio quantum chemistry, as well as new polarizable force field parameters
for nanoporous graphene.
PLAY WITH MOLECULES AT SURFACES
Kai Wu
College of Chemistry and Molecular Engineering, Peking University, Beijing
100871, China
Controlling molecular adsorption and assembly at surface is one of the major
challenges in surface chemistry. While molecular adsorption is dictated by
molecule-substrate interaction, molecular assembly is primarily balanced by weak molecule-molecule
and molecule-substrate interactions under vacuum conditions. Therefore, a slight change in the building
block structure or an input of small external energy would drastically change the balance and the
assembling structures at surface. This presentation will show how to utilize hydrogen and halogen bonds
and metal-ligand coordination as well to construct and control molecular porous and fractal assemblies
at various surfaces, followed by demonstration with explicit examples that the surface molecular
assembly strategy can be effectively exploited to tweak the reactions and properties of molecules at
surfaces.
SYNTHESIS AND CATALYTIC BEHAVIOUR OF ANISOTROPIC CERIA
NANOMATERIALS
Rui Liu, Jun Ke, Ling-Dong Sun & Chun-Hua Yan*
Beijing National Laboratory for Molecular Sciences, State Key Laboratory of
Rare Earth Material s Chemistry and Applications, College of Chemistry and
Molecular Engineering, Peking University, Beijing, 100871, China
Cerium is the most abundant element among the rare earth family. Ceria-based materials are attractive
due to their widespread applications in three-way catalysis, oxygen sensors, solid oxide fuel cells,
polishing materials, reactive oxygen species scavenger and UV blockers, etc.1 To improve the catalytic
performance, controlled synthesis of ceria-based nanomaterials with desirable composition, uniform
morphology, and tunable surfaces has received great attention in the past decade. Among the shape-
tunable ceria nanocrystals, anisotropic one-dimensional (1D) wires and rods, two-dimensional (2D)
plates and sheets have been demonstrated to possess rather high-catalytic activities because they
expose rough and active (110) or (100) facets, on which oxygen defects are easy to form.2
To obtain low-symmetry morphologies, we have developed a facile hydrothermal treatment without
addition of any templates to prepare high-aspect-ratio ceria nanorods.3 Moreover, lanthanide uniformly
doped (110)-oriented CeO2 nanowires from La to Lu were prepared by controlling the redox property of
Ce(III)/Ce(IV). In this approach, Ce3+ precursor was dissolved in a high-concentration alkaline solution,
forming one-dimensional Ce(OH)3 intermediates with hexagonal structure. The nanowires transformed
into CeO2:Ln nanowires without prominent change in shape upon calcination at 300 °C for 1 h.4 We have
also developed the synthesis of multi-layer and single-layer ceria nanoplates by the injection method in
the oleic acid (OA)/oleylamine (OAm) system. The nanoplates expose six (100) facets and have a
thickness of 0.6 ± 0.1 nm for the layers in the multi-layer nanoplates and 1.1 ± 0.2 nm for the single-layer
nanoplates. Mechanism study shows that our ceria nanoplates are synthesized through a two-
dimensional intermediate. The synthesis method could be easily applied to the synthesis of all the other
lanthanide oxide nanoplates or nanodisks (except Pm2O3).
According to the experimental results and density functional theory simulations, the catalytic activity of
CeO2:Ln nanowire was improved with respect to the undoped samples because of the activated surface
oxygen and the enhanced CO chemisorption ability due to the introduction of the LnCeʹ defects. On the
other hand, we have tested the catalytic activity of the single-layer nanoplates in the reaction of methyl
benzoate and n-octyl alcohol, which show high catalytic activity due to the atomic thickness and specific
surface area. [1] Zhou H. P., Wu H. S., Shen J., Yin A. X., Sun L. D., Yan C.H. J. Am. Chem. Soc. 2010, 132, 4998-4999.
[2] Yuan Q., Duan H. H., Li L. L., Sun L. D., Zhang Y. W., Yan C. H. J. Colloid Interf. Sci. 2009, 335, 151-167.
[3] Mai H. X., Sun L. D., Zhang Y. W., Si R., Feng W., Zhang H. P., et al. J. Phys. Chem. B. 2005, 109, 24380-24385.
[4] Ke J., Xiao J. W., Zhu W., Liu H., Si R., Zhang Y. W., et al. J. Am. Chem. Soc. 2013, 135, 15191-15200.
CELLULAR SYNTHESIS OF PROTEIN CATENANES AND OTHER
COMPLEX TOPOLOGIES
Wen-Bin Zhang
Department of Polymer Chemistry and Physics, College of Chemistry and
Molecular Engineering, Peking University, Beijing, 100871, P. R. China
Genetically encoded chemistry provides versatile control over the process of
chemical reactions and the resulting materials. The spontaneous formation of an isopeptide bond
between a peptide tag and its protein partner is a genetically encoded, cell-compatible, highly specific
and efficient chemistry for protein/peptide conjugation, as demonstrated in the pair of
SpyTag/SpyCatcher.1 Through protein engineering, we have successfully developed a chemical toolbox
of genetically encoded chemical reactions. In this talk, I will present our recent results on new features
that we introduced into the genetically encoded reactive pairs, the use of such tools in creating proteins
with complex topologies (such as protein catenanes)2,3, and the application of such nonlinear proteins as
bioactive materials. 4
[1] Zakeri, B.; Fierer, J. O.; Celik, E.; Chittock, E. C.; Schwarz-Linek, U.; Moy, V. T.; Howarth, M. Proc. Natl. Acad.
Sci. USA 2012, 109, E690.
[2] Wang, X.-W.; Zhang, W.-B.* Cellular Synthesis of Protein Catenanes. Angew. Chem. Int. Ed. 2016, 55, 3442.
[3] Zhang, W.-B.; Sun, F.; Tirrell, D. A.; Arnold, F. H. J. Am. Chem. Soc. 2013, 135, 13988.
[4] Sun, F.; Zhang, W.-B.; Mahdavi, A.; Arnold, F. H.; Tirrell, D. A. Proc. Natl. Acad. Sci. USA 2014, 111, 11269.