Chemical Communications Blog

Congratulations to Pei-Xi Wang who has published his #ChemComm1st article ‘Lyotropic Liquid Crystalline Phases of Anisotropic Nanoparticles of Organic-Inorganic Metal Halide Perovskites: Photoluminescence from Self-Assembled Ordered Microstructures of Semiconductors‘ within the last month. We recently spoke to Pei-Xi about his experiences as a first-time independent author. Find out more in our interview below.

What are the main areas of research in your lab and what motivated you to take this direction?
Motivated by the charming microscopic orderliness of liquid crystalline phases, which provides a relatively simple and controllable bottom-up biomimetic approach to various fascinating hierarchical structures existing in plants and animals, we decided to focus on the development of novel lyotropic liquid crystals as well as the fabrication of functional composite nanomaterials based on them. Currently, we are trying to build a general synthesis method that can transform different types of organic-inorganic metal halide perovskites into colloidal liquid crystalline mesogens, and to further use these semiconducting soft anisotropic materials in optoelectronic devices.

Can you set this article in a wider context?
The functionalization of many types of conventional colloidal liquid crystalline mesogens, such as vanadium pentoxide nanoribbons, polypeptides, and cellulose nanocrystals is usually difficult, i.e., it is hard to endow them with specific energy band gaps or other desired physical properties by chemical modification. In this article, the feasibility of synthesizing mesogenic nanoparticles of organic-inorganic metal halide perovskites has been proven, as metal halide perovskites are a class of materials with excellent structural and compositional diversity, it would be possible to systematically develop a large family of colloidal lyotropic liquid crystals with semiconductivity, luminescence, ferroelectricity, magnetism, chirality, or other preferred features.

What do you hope your lab can achieve in the coming year?
Since late March, my first two graduate students, Ting-Ting Zhou and Cai-Yun Zhao have started to work in the lab. In the coming year, I hope they can find their real research interests either in the field of lyotropic liquid crystalline materials, where I would be able to support them with the experience and knowledge I have gathered during my Ph.D. and postdoctoral studies, or in any other fields attracting them or fortunately initiated by themselves, where they can enjoy the exciting process of making new discoveries every day.

Describe your journey to becoming an independent researcher.
From 2007 to 2009, when I was a student in Henan Experimental High School, I learned a lot of classical and modern physics for the Chinese Physics Olympiad, during which time I was strongly attracted by the conciseness of physical principles such as the Maxwell equations. However, I did not have a clear understanding of scientific research until the completion of my first project under the supervision of Prof. Mark J. MacLachlan (I would also like to acknowledge Dr. Vitor M. Zamarion for his kind help with that project). There was a moment when I accidentally realized that the circular dichroism signal of a chiral nematic mesoporous silica film filled with a Prussian blue analogue should be the product of the absorption and CD spectra of the unfilled film, which was for the first time I noticed that there might be some interesting mathematical relationships behind the seemingly tedious experimental data. From then on, I learned how to build a comprehensive view of the materials and physical phenomena involved in my studies, and started to enjoy the hunt for undiscovered phenomena in the jungle of my experiments.

What is the best piece of advice you have ever been given?
It would be a Chinese saying “吾生也有涯, 而知也无涯, 以有涯随无涯, 殆已”, which means “my lifespan is limited, while knowledge is infinite, spending my limited time on pursuing unlimited knowledge is harmful”.

Why did you choose to publish in ChemComm?
In the past several years, I have been inspired by many classical research articles published in ChemComm, therefore I believe that ChemComm is a great journal for rapidly reporting new chemical discoveries with clear scientific significance and authenticity.

Dr. Pei-Xi Wang was born in China in September 1992. He received his B.Sc. in chemistry from Jilin University in July 2014. He then moved to Vancouver in August 2014 to pursue a Ph.D. and completed his doctorate in chemistry at the University of British Columbia in October 2018, where under the supervision of Prof. Mark J. MacLachlan, he studied the structures and transformation of chiral nematic liquid crystalline tactoidal microphases of cellulose nanocrystals by scanning electron microscopy. Afterwards, he worked as a postdoctoral researcher in the MacLachlan group at UBC (2019/01-2019/12) and in the Edward H. Sargent group at the University of Toronto (2020/01-2020/11). Pei-Xi started his independent research as an associate professor in early December 2020 at the Suzhou Institute of Nano-Tech and Nano-Bionics of the Chinese Academy of Sciences, where he focuses on the development of colloidal lyotropic liquid crystals of semiconducting organic-inorganic metal halide perovskites.

Read Pei-Xi’s #ChemComm1st article and others in our growing collection, ChemComm Milestones – First Independent Article. Follow us on Twitter for all of the latest #ChemCommMilestones news.

Bartosz Lewandowski’s ChemComm1st article ‘Chiral recognition of amino-acid esters by a glucose-derived macrocyclic receptor‘ is available now. We wanted to find out more about Bartosz and what it was like to reach this ChemComm Milestone in our interview below.

Read our with Bartosz interview here.

What are the main areas of research in your lab and what motivated you to take this direction?
The main topic which we are investigating is the use of monosaccharides as building blocks to create supramolecular receptors and assemblies. We want to take advantage of the intrinsic features of these biomolecules (e.g. water solubility, biocompatibility, modularity) and create new types of supramolecular systems and devices for controlled and selective encapsulation, transport and chemical transformations of molecular entities.

I was “hooked on sugars” during my Ph.D. studies in the group of Prof. Sławomir Jarosz where I explored the chemistry of sucrose. This was a great learning experience for me as I got to know the challenges associated with sugar chemistry, but was also able to appreciate the great potential of these biomolecules. And I felt that there are many exciting things that can be done with sugars, particularly in the context of supramolecular chemistry, which is exactly what we are working on right now.

Can you set this article in a wider context?
The ability to separate or detect enantiomers of bioactive molecules is of high importance since they very often have vastly different chemical and biological properties. Achieving this goal in aqueous media is particularly relevant if one wants to develop analytical tools for diagnostic or therapeutic purposes. Within our manuscript we demonstrated the efficacy of a simple glucose-based macrocycle for differentiation of amino-acid enantiomers in aqueous environments. Thus our results open up exciting opportunities for the development of molecular tools for chirality sensing and enantiomer separation of bioactive molecules.

What do you hope your lab can achieve in the coming year?
Firstly, I hope that we can build on the results we just published and develop further carbohydrate-based chiral receptors. We plan to utilize the modularity of monosaccharides and their potential for functional fine-tuning to create supramolecular receptors with additional attractive features (e.g. increased chemoselectivity, fluorescence). My other ambition for this and following years is to explore other research pathways with carbohydrate-based macrocycles and use them as building blocks to create novel functional supramolecular assemblies and perhaps even molecular machines.

Describe your journey to becoming an independent researcher.
I think the moment when I started to seriously consider becoming an academic researcher was when I joined the group of Prof. David Leigh for my post-doc. Designing and creating molecular machines is a tremendous scientific challenge. But for me it also contained an element of pure joy and excitement coming from assembling small molecular fragments piece-by-piece into a device that can perform complex tasks. And the satisfaction when the final goal was achieved rewarded all the difficulties and frustration that came along the way. And that’s when I thought “Yes, this is what I want to do in life.” That thought was then reinforced when I joined the group of Prof. Helma Wennemers. Working on highly multidisciplinary cutting-edge research and being immediately entrusted with supervision and guidance for junior co-workers (both students and Ph.D. students) allowed me to greatly mature as a scientist. It also inspired me to create my own research plan for the future. And at the end of 2015 I successfully applied for the position of a Senior Scientist in the Wennemers Group at the Laboratory of Organic Chemistry, ETH Zürich. This is a unique position which gives me the opportunity to build my independent research line while remaining an integral part of Prof. Wennemers’ team where we pursue exciting research projects.

What is the best piece of advice you have ever been given?
I’ve been very fortunate to have worked with many incredibly supportive people and I’ve received a lot of great advice from them. The two pieces that stuck with me the most over the years are:
“If you keep doing excellent work, good things will eventually come your way.” and “You should never talk yourself out of an experiment.”

Why did you choose to publish in ChemComm?
First of all because it’s one of the leading chemistry journals in the world with a broad impact on the scientific community. It’s also among my favourite journals to read when I screen recent literature. Finally, I was very keen on publishing my first independent work in ChemComm as this is where the most significant results of my PhD were published.

Bartosz Lewandowski was born in Kętrzyn, Poland in 1981. He obtained his M.Sc. degree in Chemical Technology from the Warsaw University of Technology in 2004. He carried out his Ph.D. research on synthesis and complexing properties of sucrose-based macrocycles in the Institute of Organic Chemistry, Polish Academy of Sciences in Warsaw, in the group of Prof. Sławomir Jarosz. He successfully defended the Ph.D. thesis in 2009 and in the same year became the FNP (Foundation for Polish Science) Post-Doctoral Fellow in the group of Prof. David Leigh at the University of Edinburgh. There he worked on the design, synthesis and operation of molecular machines. In 2013 he joined the group of Prof. Helma Wennemers at the ETH Zürich as a Marie Curie Post-Doctoral Fellow, working on oligoproline-based macrocycles and supramolecular assemblies for molecular recognition and catalysis. In 2016 he was appointed as a Senior Scientist in the Wennemers Group. His research focuses on using monosaccharides to create supramolecular receptors and assemblies for selective binding, transport and chemical transformations of guest molecules.

Read Bartosz’s ChemComm1st article and others in our collection ChemComm Milestones – First Independent Article. Follow @ChemCommun for all of the latest journal and #ChemCommMilestones news.

We are pleased to let you know that Ellen Robertson has reached a ChemComm Milestone with her #ChemComm1st article: ‘Synthesis and characterization of plasmonic peptoid nanosheets‘.

Find out about Ellen and her research below.

What are the main areas of research in your lab and what motivated you to take this direction?
I’m a physical chemist by training and my research specifically focuses on colloid and interfacial science. In my lab, we are working to develop new classes of surface enhanced Raman scattering sensors based on the co-assembly of two-dimensional peptoid scaffolds and nanoparticles at fluid surfaces. Our goal is to use these sensors to detect environmental pollutants that are prevalent in Upstate New York. I’ve always been interested in using chemistry to solve environmental problems. In college, I worked on a service-learning project in my introductory chemistry course in which we collected soil and water samples from the community and tested them for lead. I realized from this example how chemistry can be used for the good of the environment and its inhabitants, and it is my aim as a chemist to do this kind of good.

Can you set this article in a wider context?
The research presented in this article clearly demonstrates how the power of interfacial self-assembly can be implemented to fabricate new nanomaterials with interesting properties. I believe the method described in the paper for forming plasmonic peptoid nanosheets can likely be extended to creating two-dimensional arrays of magnetic, semiconducting, antibacterial, and catalytic nanoparticles. This generalizable strategy has the potential for creating a new class of two-dimensional nanomaterials that have a wide range of optical, electronic, and magnetic properties.

What do you hope your lab can achieve in the coming year?
In the upcoming year, my lab hopes to test the limits of our peptoid-directed assembly mechanism for forming new two-dimensional nanomaterials. We are planning to see if we can fine-tune the properties of these nanosheets by varying the nanoparticle concentration, size, surface chemistry, and material used in the synthesis.

Describe your journey to becoming an independent researcher.
My journey to becoming an independent researcher was the result of my love of chemistry and some timely opportunities that I was able to pursue. I started my research path as an undergraduate at Kalamazoo College. I worked in Jeff Bartz’s lab studying the gas phase dissociation of NOx compounds. Jeff encouraged me to pursue summer research opportunities, and I was grateful to have the opportunity to work for one summer at Dartmouth College making cobalt nanoparticles in Barney Grubb’s lab, and one summer at the University of Oregon studying interfacial assembly in Geraldine Richmond’s lab. I loved the Richmond lab research so much, I returned as a graduate student to complete my Ph.D. research, which focused on understanding the assembly of polyelectrolytes at the oil-water interface using vibrational sum frequency spectroscopy (VSFS) and interfacial tension measurements. While in graduate school, I worked on collaborative project between Geri’s lab and Ron Zuckermann’s lab at Lawrence Berkeley National Lab in which I characterized peptoid monolayers using VSFS. The aim of these studies was to assign spectroscopic signatures to peptoid monolayers that were capable of forming peptoid nanosheets via monolayer compression and collapse. Working on this collaboration was a great experience and prompted me to apply for and accept a postdoctoral position in Ron’s lab. I spent two years working in Ron’s lab using interfacial tension and rheology to determine the factors that affect the ability of different peptoid sequences to form monolayers capable of collapse into nanosheets. Following my postdoctoral appointment, I returned to Kalamazoo College as a Visiting Assistant Professor of Chemistry. It was here that I realized my love of working with undergraduates in the research lab, and so I sought out a position at a primarily undergraduate institution. Now an Assistant Professor of Chemistry at Union College, my independent research combines elements of my graduate research (self-assembly at the oil-water interface) with my post-doctoral research (using peptoids to create new materials).

What is the best piece of advice you have ever been given?
Some of the best advice that I have ever been given is to embrace a growth mindset. With a growth mindset, we can always envision new ways to improve, both professionally and personally. Failure no longer becomes an obstacle, but an opportunity to learn something new and grow.

Why did you choose to publish in ChemComm?
I chose to publish in ChemComm because this journal is well known for publishing novel research that is of immediate and broad interest to those in the field of chemistry. I was so excited when my lab discovered the plasmonic peptoid nanosheets described in our recent ChemComm publication. I realized that the synthesis of these novel materials through peptoid monolayer collapse at the oil-water interface opened the door for creating a brand-new class of two-dimensional nanomaterials. I wanted to share this discovery with a broad audience of chemists that could see the utility in these new materials and the method used to prepare them. I am grateful for the opportunity that ChemComm has given me to share my science story.

Back: Ellen Robertson, Chris Avanessian, Anna Mahony, Elizabeth Whitney
Front: Misty Zaczyk, Mindle Shavy Paneth, Jana Davis

Professor Ellen J. Robertson received her Ph.D. in physical chemistry at the University of Oregon where she studied the assembly of polyelectrolytes at the oil-water interface using vibrational sum frequency spectroscopy. Ellen then held a post-doctoral appointment at Lawrence Berkeley National Lab where she studied the assembly mechanism of peptoid nanosheets at the air-water interface. After serving as a Visiting Assistant Professor of Chemistry at Kalamazoo College for two years, Ellen was hired as an Assistant Professor of Chemistry at Union College, a small private liberal arts institution in Upstate New York. Here, she has established her research program, the overall goal of which is to develop peptoid-based surface enhanced Raman scattering sensors for detecting pollutants that are persistent in Upstate New York. Her work has been funded by The Community Foundation for the Greater Capital Region’s Bender Scientific Fund. Ellen is dedicated to undergraduate education in chemistry, both in the classroom and in the research lab. At Union, Ellen teaches courses in general and physical chemistry and works with undergraduates in her research lab. She also co-advises Union College’s American Chemical Society Student Chapter. Outside of chemistry, Ellen is an avid tennis player, competing both at the local and national level. 

You can find all of our #ChemComm1st articles in ChemComm Milestones – First Independent Articles. Follow @ChemCommun for all of the latest ChemComm Milestones updates.