Congratuations to Shi (Shirely) Shi: MSE Topping Grant 2020

​Based on the scholarly accomplishments, service to the school, as well as advisor’s recommendation, Shirley has been selected to receive a one-time topping grant in the amount of $2000 which is in addition to the stipend they currently receive. Funding for the topping grant has been provided by the generous support of the Jewell Family Fellowship Endowment.

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Publication in Nanoscale: Jaewan (Albert) Ahn and Junki Kim

November, 2019

We report the fabrication of Ag-Au cuboctahedral nanoboxes enclosed by {100} and {111} facets, respectively, through the orthogonal deposition of Au on two different facets of Ag cuboctahedra. Specifically, we titrate aqueous HAuCl4 into an aqueous mixture containing Ag cuboctahedra, ascorbic acid, and NaOH (under a basic condition), in the presence of poly(vinylpyrrolidone) (PVP) and cetyltrimethylammonium chloride (CTAC), respectively

Congratulations to Dr. Jae Wan (Albert) A; Ahn

October, 2019

Albert has successfully defended his thesis work --Rational Synthesis of Multimetallic Nanocrystals

for Plasmonics and Catalysis -- on October 31, 2019. He is ready for his next chapter of professional life.

 

An introduction note from Dr. Qin before Albert's defense:

"Good morning everyone. Albert was born and raised in an academic family. He spent a few years of primary school in Florida when his father was a visiting scholar there. With tremendous support from his parents, Albert returned to the states in 2008. After a few years of high school education in Georgia, he became the proud freshman of Georgia Tech in 2011. I first met with Albert when he took my Nanomaterials class in 2013 and since then he has been working in the Qin Lab first as an undergraduate researcher and then a PhD student. In fact, he became the most senior person in the Qin Lab! In the past four years, Albert has published 5 first-author papers, together with additional 5 co-author papers. Albert had been my leading TA of MSE 2001 course over the past few years and he was extremely well-recognized from the students through his efforts to support students during office hours and to lead discussions on the homework questions in the classroom setting. Next, Albert will defend his thesis work!"

Publication in Chemistry of Materials: Jaewan (Albert) Ahn

October 2019

We report a general method based on galvanic replacement for the fabrication of nanoscale, multi-metallic, cage cubes by confining the drilling of Ag to the center of each side face of a Ag nanocube encased by Ag-Au alloy frames. In a typical process, we disperse Ag@Ag-Au core-frame nanocubes in an aqueous solution of cetyltrimethylammonium chloride, followed by the titration of an aqueous solution of the precursor under ambient conditions. The same strategy also works for other salt precursors, including Pt(II), Pd(II), and Au(III), but the size of the holes may vary depending on the stoichiometry involved in the galvanic replacement reaction.

Publication in Angewandte Chemie International Edition: Shi (Shirley) Shi

September 2019

Bifunctional nanocrystals with integrated plasmonic and catalytic activities hold great promise for analyzing chemical reactions byin situsurface-enhanced Raman spectroscopy. This review starts with a brief introduction to the general strategies for designing such nanocrystals, followed by the presentation of four typical examples, including their fabrication, characterization, and potential limitation. We then use the reduction of 4-nitrothiophenol and oxidation of 4-aminothiophenol as two model systems to demonstrate the capabilities of these bifunctional nanocrystals to monitor chemical reactions for the elucidation of reaction mechanisms and measurement of kinetics. We conclude this review with perspectives on further development of these bifunctional nanocrystals into a viable platform for investigating other types of catalytic reactions.

Publication in Journal of Physical Chemistry C: Jaewan (Albert) Ahn

August 2019

We report an investigation of the adsorption of thiol and isocyanide molecules on colloidal Ag nanocubes through surface-enhanced Raman scattering (SERS). We demonstrate that 4-nitrothiophenol could readily bind to the Ag surface through strong thiol-Ag interaction. Likewise, 4-aminothiophenol also adsorbs onto Ag quickly, but gives much weaker SERS signals relative to 4-nitrothiophenol because the electron-donating amine group would retard the chemical enhancement of SERS. Different from thiols, 1,4-phenylene diisocyanide binds to Ag surface through a relatively weak, sigma-donation bond. We further investigate the competitive binding of thiol and isocyanide, demonstrating the capability of thiol to inhibit the adsorption of isocyanide when these two ligands are presented in a mixture.

Publication in ChemNanoMat: Jaewan (Albert) Ahn

July 2019

Facet-selective etching and deposition, as determined by the landscape of surface energy, represent two powerful methods for the transformation of noble-metal nanocrystals into nanostructures with complex shapes or morphologies. This review highlights the use of these two methods, including integration of them, for the fabrication of novel monometallic and bimetallic nanostructures with enhanced properties. 

Congratulations to Shi (Shirley) Shi

April, 2019

​Shi (Shirley) Shi received the 1st place award in the 7th Annual School of Materials Science and Engineering Undergraduate and Graduate Poster Session for her poster titled "Shining Light on Metal Nanocrystals for Collecting the Fingerprint Information of Molecules on Their Surfaces " competing under nanomaterials category.

Publication in Nanoscale: Zheyu Luo

March 2019

We report the fabrication of Ag-Pd concave nanocrystals by introducing the Pd(II) precursor into an aqueous suspension of Ag nanocubes in the presence of cetyltrimethylammonium chloride (CTAC) under ambient conditions. Different from the previously reported work that involved the oxidation of Ag and deposition of Pd at random sites on the surface for the generation of Ag-Pd hollow nanocrystals, we demonstrate that the Cl−ions from CTAC can confine the oxidation of Ag atoms to the side faces of a nanocube while the resultant Pd atoms are deposited on the edges in an orthogonal manner. By controlling the amount of the Pd(II) precursor involved in a synthesis, we can transform Ag nanocubes into Ag-Pd nanocrystals with different degrees of concaveness for the side faces and controllable Pd contents.

Publication in Chemistry of Materials: Luo Zhang

January 2019

We report the defect-assisted deposition of Au on Ag nanocubes for the generation of Ag@Au core-shell nanocubes with three to eight atomic layers. In a standard protocol, we disperse Ag nanocubes in an ethylene glycol (EG) solution containing poly(vinylpyrrolidone) and then titrate aqueous HAuCl4 at 110 oC.  We also use surface-enhanced Raman scattering to characterize the transformation of the core-shell nanocubes with a Ag-dominated to a Au-enriched outermost surface as the Au shell thickness is increased. The as-obtained Ag@Au core-shell nanocubes with a Au shell of eight atomic layers are stable in aqueous 30% H2O2 for at least 12 h, together with remarkable thermal stability in EG at 110 oC for 6 h.

Congratulations to Dr. Yiren Wu

November 2018

Yiren has successfully defended her thesis work -- Colloidal Silver Nanocrystals and their Derivatives: Synthesis, Properties, and Applications -- on November 20, 2018. She is ready for her next challenge.

 

An introduction note from Dr. Qin before Yiren's defense:

"Good afternoon! Welcome to Yiren’s thesis defense! Yiren was born and raised in Taizhou, Zhejiang province of China. After she received her bachelor degree of polymer science and engineering from Zhejiang University, she came to the states and became our first year MSE PhD student. Yiren is a student that always strives for her very best both in course work and in research. She is also a chemical safety capital in the Qin lab, responsible for each quarter safety reports and inspections. I am extremely grateful to her dedication to our two NSF sponsored projects from 2014 to present, during her four-year span in graduate school. Remarkably, her most recent work opens up possibilities to explore new research directions. Today is very special day for Yiren to mark her timeline and her mother is also joining the crowd, bringing strong support from her family back in China! Let's welcome Yiren to present her thesis work."

Publication in JACS Article: Yiren Wu

June 2018

We report the use of 2,6-dimethylphenyl isocyanide (2,6-DMPI) as a spectroscopic probe to study the heterogeneous nucleation and deposition of Pd on Ag nanocubes under different conditions by surface-enhanced Raman scattering (SERS). As a major advantage, the spectroscopic analysis can be performed in situ and in real time with the nanoparticles still suspended in the reaction solution. When 2,6-DMPI molecules were introduced into the reaction solution, we further demonstrated in situ tracking of heterogeneous nucleation and early-stage deposition of Pd on Ag nanocubes by monitoring the evolution of -NC bands for both Ag and Pd surface atoms as a function of reaction time. This in situ technique opens up the opportunity to investigate the roles played by reaction temperature and the type of Pd(II) precursor in influencing the heterogeneous nucleation and growth of bimetallic nanocrystals. The sensitivity of isocyanide group to Pd atoms helps elucidate some of the details on the reduction, deposition, and diffusion processes involved in heterogeneous nucleation.

Publication in Journal of Materials Chemistry C Review: Yun Zhang

May 2018

This review reports the recent progress in the rational design, synthesis, and applications of a new class of bimetallic nanocrystals with integrated SERS and catalytic activities for monitoring catalytic reactions in situ. The results demonstrate the new ubiquity of SERS that leverages the bifunctional probes to characterize the reaction intermediates and products by vibrational spectroscopy in situ, making it possible to monitor the dynamic processes of catalysis.

Congratulations to Dr. Dong Qin: 2018-2020 Provost Teaching and Learning Fellow

April 2018

The vision of this program is to create a hub-and-spoke model that connects the expertise of evidence-based teaching and learning professionals in the Center for Teaching and Learning with the expertise of disciplinary faculty in each college/school. The goal is to strengthen teaching and learning in the colleges through this embedded system of on-going instructional support and special initiatives.

Congratulations to Shi (Shirley) Shi

April 2018

Shi (Shirley) Shi received the 1st place award in the 6th Annual School of Materials Science and Engineering Undergraduate and Graduate Poster Session for her poster titled "Bringing Copolymers to the Synthesis of Metal Nanoparticles: Opportunities and Challenges" competing under first year graduate student category.

Congratulations to Zheyu (Jerrry) Luo

April 2018

Zheyu (Jerry) Luo received the 1st place award in the 6th Annual School of Materials Science and Engineering Undergraduate and Graduate Poster Session for his poster titled "Transformation of Silver Nanocubes into Bimetallic Nanocrystals with Desired Optical and Catalytic Properties " competing under nanomaterials category.

Congratulations to Jaewan (Albert) Ahn

April 2018

Jaewan (Albert) Ahn received the 3rd place award in the 6th Annual School of Materials Science and Engineering Undergraduate and Graduate Poster Session for his poster titled "Single Atom Catalysis: the Next Generation of Heterogeneous Catalysis" competing under nanomaterials category.

Congratulations to Dr. Dong Qin

April 2018

Dr. Dong Qin is the recipient of Geoffrey G. Eichholz Faculty Teaching Award in 2018. Since 2012, she always strives her very best to teach all courses with her wholehearted dedication to the success of every student and commitment to fairness. This is the second teaching award from the Tech and she is a receipt of the GT-CETL/BP Junior Faculty Teaching Excellence Award in 2015.

Publication in Nanoscale Article: Zhiwei Zhang

April 2018

We report a facile route to the synthesis of Ag@Au-Pt trimetallic nanocubes in which the Ag, Au, and Pt atoms are exposed at the corners, side faces, and edges, respectively. Our success relies on the use of Ag@Au nanocubes, with Ag2O patches at the corners and Au on the side faces and edges, as seeds for the site-selective deposition of Pt on the edges only in a reaction system containing ascorbic acid (H2Asc) and poly(vinylpyrrolidone). At an initial pH of 3.2, H2Asc can dissolve the Ag2O patches, exposing the Ag atoms at the corners of a nanocube. Upon the injection of H2PtCl6 precursor, the Pt atoms derived from the reduction by both H2Asc and Ag are preferentially deposited on the edges, leading to the formation of Ag@Au-Pt trimetallic nanocubes.

Congratuations to Yiren Wu and Jaewan Ahn: MSE Topping Grant 2018

March 2018

Based on the scholarly accomplishments, service to the school, as well as advisor’s recommendation, both Yiren and Albert have been selected to receive a one-time topping grant in the amount of $2000 which is in addition to the stipend they currently receive. Funding for the topping grant has been provided by the generous support of the Jewell Family Fellowship Endowment.

Publication in Chemistry of Materials Article: Yun Zhang

February 2018

We report a simple and general method for the production of Ag-Rh bimetallic nanostructures with a unique integration of plasmonic and catalytic properties exemplified by these two metals, respectively. In a typical process, we titrated a Rh(III) precursor into a polyol suspension of Ag nanocubes held at 110 oC in the presence of ascorbic acid and poly(vinylpyrrolidone). By simply controlling the amount of Rh(III) precursor, we observe the transformation of Ag nanocubes into Ag-Rh core-frame and then Ag-Rh hollow nanocubes with a high porous surface. Upon selective removal of Ag by wet etching, the hollow nanocubes evolve into Ag-Rh and then Rh nanoboxes with highly porous walls. While the Ag-Rh core-frame nanocubes show a unique integration of the plasmonic and catalytic properties characteristic of Ag and Rh, respectively, the Rh nanoboxes show remarkable activity toward the catalytic degradation of environmental pollutants such as organic dyes.

Congratulations to Dr. Dong Qin

February 2018

Dr. Qin has been awarded tenure in the School of Materials Science and Engineering at Georgia Tech, effective August 15, 2018.

PhD Thesis Proposal - Jaewan Ahn

February 2018

Albert successfully defended his thesis proposal: Rational Design and Synthesis of Silver-Based Bimetallic and Trimetallic Nanocrystals for Plasmonics and Catalysis

Graduation 2017: Xiaojun Sun and Junki Kim

December 2017

Warmest congratulations to Dr. Xiaojun Sun and Junki Kim for the completion of PhD and Master work at Georgia Tech, respectively. Best wishes to their future endeavors!!

Publication in ACS Nano Article: Jaewan Ahn

December 2017

We report a facile synthesis of Ag nanocubes with concave side faces and Au-Ag alloy frames, namely Ag@Au-Ag concave nanocrystals, by titrating HAuCl4 solution into an aqueous mixture of Ag nanocubes, ascorbic acid (H2Asc), NaOH, and cetyltrimethylammonium chloride (CTAC) at an initial pH of 11.6 under ambient conditions. Different from all previous studies involving poly(vinylpyrrolidine), the use of CTAC at a sufficiently high concentration plays an essential role in carving away Ag atoms from the side faces through galvanic replacement. Concurrent co-deposition of Au and Ag atoms via chemical reduction at orthogonal sites on the surface of Ag nanocubes leads to the generation of Ag@Au-Ag concave nanocrystals with well-defined and controllable structures.

New Journey: Dr. Xiaojun Sun

November 2017

Xiaojun will be joining KLA Tencor after his PhD commencement in December. Congratulations and best wishes to his future endeavors in the bay area!

Publication in Nanoscale Article: Xiaojun Sun

September 2017

We report a facile synthesis of Pt-Ag nanocages with walls thinner than 2 nm by depositing a few atomic layers of Pt as conformal shells on Ag nanocubes and then selectively removing the Ag template via wet etching. We further demonstrate that the as-obtained nanocages with a composition of Pt42Ag58 exhibit enhanced catalytic activity toward the oxygen reduction reaction, with a mass activity of 0.30 A mg−1 and a specific activity of 0.93 mA cm−2, which are 1.6 and 2.5 times, respectively, greater than those of a commercial Pt/C catalyst.

September 2017

Enriching Silver Nanocrystals with a Second Noble Metal:

 

Silver is perhaps the best choice of material for plasmonics and related applications owing to its relatively low cost and favorable dielectric functions. Over the past two decades, significant progress has been made in the synthesis of Ag nanocrystals with controlled shapes and sizes to tailor their properties and thus optimize their performance in a range of applications. In particular, Ag nanocrystals have been prepared with sharp features on the surface to drastically augment their surface-enhanced Raman scattering (SERS) activity. However, the sharp features tend to vanish due to the high susceptibility of Ag towards oxidative etching. As another pitfall, Ag is limited in terms of catalytic application as it only shows activity towards oxidation reactions such as epoxidation, not reduction reactions.

 

One can address the aforementioned limitations of Ag nanocrystals by introducing a second noble metal (M) such as Au, Pd, or Pt to generate Ag-M bimetallic nanocrystals in the core-frame and core-shell structure. When the M atoms are selectively deposited on the edges of a Ag nanocrystal, for example, a Ag@M core-frame nanocrystal is formed. In this structure, the excellent plasmonic and SERS properties of the Ag core are still retained while the deposited M brings in new catalytic capabilities. Alternatively, when the M atoms are conformally deposited on the entire surface, a Ag@M core-shell nanocrystal is created.10 In this case, the M shell can greatly improve the chemical stability of the particle, in addition to the new catalytic properties associated with M. If the shell is kept below 1–2 nm thick, the excellent plasmonic and SERS properties of the Ag core can still be leveraged. Significantly, both SERS and catalytic properties can be integrated in the core-frame and core-shell nanocrystals to offer a unique probe for in situ detection and analysis of catalytic reactions by SERS.

Congratulations to Xiaojun Sun

August 2017

Xiaojun has successfully defended his thesis work -- Bimetallic Nanocrystals for Applications in Plasmonics and Catalysis -- on August 2, 2017. He is ready for his next challenge.

 

An introduction note from Dr. Qin before Xiaojun's defense:

 

"Good morning! Welcome to Xiaojun’s thesis defense! Xiaojun was born and raised in Shanghai. After he received his bachelor degree of materials science and engineering from Shanghai Jiaotong University, he came to the states and become the first year PhD student of Material Science and Engineering at Georgia Tech. I still vividly remembered the moment when I had my first meeting with Xiaojun in my office about four years ago. As you can imagine, I was trying very hard to recruit him to join the newly established Qin Lab with tons of my energy and enthusiasm. Xiao then was as calm as he is for now, but I can tell that he was excited about joining the Qin Lab. Before we both reached to a conclusion, I encouraged Xiaojun to perform a couple of survey experiments from which he demonstrated his competency.  After we both happily signed the document, we started our journey together for the next four years. Looking back, I am very fortunate to have Xiaojun become my first PhD student! We have been working together side by side closely to achieve our goals and to establish the foundation for the Qin Lab. I am extremely grateful to his commitments on the assigned projects from very beginning to the end! It is also such a joy to witness the transformation of Xiaojun from a highly motivated individual to a matured and productive researcher! Today is very special for Xiaojun to mark his timeline! Let's welcome him to present his thesis work. Xiaojun, the floor is YOURS!!"

Publication in Accounts of Chemical Research: Yiren Wu

June 2017

In this Account, we use Ag nanocubes as an example to demonstrate the fabrication of Ag@M and Ag@Ag-M (M=Au, Pd, or Pt) nanocubes with a core-frame or core-shell structure by controlling the deposition of M atoms. A typical synthesis involves the titration of Mn+ (a precursor to M) ions into an aqueous solution containing Ag nanocubes, ascorbic acid, and poly(vinylpyrrolidone) under ambient conditions.

Congratulations to Daniel Wang: 2017 Fall PURA Award

June 2017

Daniel has been selected as a recipient of a President’s Undergraduate Research Award (PURA) for Fall 2017. He become the 3rd PURA recipient from the Qin Lab.

Continuing Funding from NSF-MSN Program

May 2017

Built upon the prior success of NSF project (CHE-1412006, 2014-2017), our proposal–“Understanding Heterogeneous Nucleation in Nanocrystal Growth with Molecular Probes”–was awarded by the National Science Foundation (NSF) through the Macromolecular, Supramolecular and Nanochemistry (MSN) Program (CHE-1708300, 2017-2020).

Congratulations to Bonnie Vannatter

May 2017

Bonnie Vannatter, a freshmen of GT-MSE, is the recipient of Georgia Tech Women in Engineering scholarship sponsored by Boeing.

Congratulations to Daniel Wang

May 2017

Daniel Wang, a sophomore of GT-MSE, is the recipient of Hapman/Pentecost Scholarship.

Publication in ACS Nano Article: Yun Zhang

April 2017

We report the development of an isocyanide-based molecular probe for in situ characterizing the overgrowth of a second metal on silver nanocrystal seeds in solution by surface-enhanced Raman scattering (SERS). As the first demonstration, we elucidate that the vibrational frequency of 2,6-dimethylphenyl isocyanide (2,6-DMPI) can serve as a distinctive reporter for capturing the nucleation of Pt on the edges of Ag nanocubes in the aqueous solution containing a Pt precursor, ascorbic acid, and poly(vinylpyrrolidone) under ambient condition.

Publication in Chemistry of Materials Article: Xiaojun Sun

April 2017

This article describes a systematic study of the roles played by hydroxide in controlling the deposition of Au on Ag nanocubes for the fabrication of diversified Ag-Au bimetallic nanocrystals. The synthesis simply involves the titration of aqueous HAuCl4 into an aqueous suspension of Ag nanocubes in the presence of ascorbic acid, NaOH, and poly(vinyl pyrrolidone) at room temperature. The OH− ions from NaOH can affect the reduction kinetics of the Au(III) precursor in a number of ways and thereby the deposition pathways of the Au atoms.

MRS Spring 2017, Phoenix

April 2017

Dr Qin, Xiaojun Sun, Junki Kim, and Zhiwei (Ryan) Zhang presented three oral talks and three posters at the MRS meeting.

Congratulations to Xiaojun Sun

April 2017

Xiaojun Sun received the 2nd place award in the 5th Annual School of Materials Science and Engineering Undergraduate and Graduate Poster Session for his poster titled "Large Scale Synthesis of Silver-Enriched Nanoparticles and Their Applications" competing under the energy/electronic materials category.

Congratulations to Junki Kim

April 2017

Junki Kim received the 1st place award in the 5th Annual School of Materials Science and Engineering Undergraduate and Graduate Poster Session for his poster titled "Gold-based Cubic and Cuboctahedral Nanoboxes with Plasmonic Absorption at Near-Infrared Wavelength" competing under the undergraduate research category.

Congratulations to Albert Ahn

April 2017

Jae Wan (Albert) Ahn received the 1st place award in the 5th Annual School of Materials Science and Engineering Undergraduate and Graduate Poster Session for his poster titled "Facet-Selective Growth of Gold on Silver Nanocubes" competing under the nanomaterials category.

Publication in ChemNanoMat Article: Yiren Wu

February 2017

We report the synthesis of bifunctional Ag@SiO2/Au nanoparticles with an “islands in the sea” configuration by titrating HAuCl4 solution into an aqueous suspension of Ag@SiO2 core-shell nanocubes in the presence of NaOH, ascorbic acid, and poly(vinyl pyrrolidone) at pH=11.9. The Ag@SiO2/Au nanoparticles can serve as a bifunctional probe to monitor the stepwise Au-catalyzed reduction of 4-nitrothiophenol to 4–aminothiophenol by NaBH4 and Ag–catalyzed oxidation of 4-aminothiophenol to trans-4,4’–dimercaptoazobenzene by the O2 from air in the same reaction system.

Thank You for Being a Great Teacher

December 2016

In appreciation of her teaching style and dedication to helping students learn in MSE 4330 (Fundamentals of Nanomaterials and Nanostructures) and MSE 2001 (Principles and Applied Engineering Materials), Dr. Qin received three certificates from "Thank a Teacher Program" at Georgia Tech.

Congratulations to Yiren Wu

November 2016

Yiren successfully defended her thesis proposal -- Colloidal Hybrid Nanocrystals: Syntheses, Properties, and Applications.

PhD Thesis Proposal - Yiren Wu

November 2016

Yiren successfully defended her thesis proposal -- Colloidal Hybrid Nanocrystals: Syntheses, Properties, and Applications.

Publication in Chemistry of Materials Article: Chia-Wei Wang

September 2016

We report a simple and versatile system for generating highly concentrated H2O2 on the surface of nanoparticles through enzymatic oxidation of glucose. It involves immobilization of glucose oxidase, a negatively charged enzyme, on the surface of a positively charged metal nanoparticle via electrostatic attraction. Upon the introduction of glucose at a concentration of 1.7 mM, this system is able to produce enzymatic H2O2 on the surface of the nanoparticle, with oxidation power equivalent to that of aqueous H2O2 at a concentration of 5 M when it is directly added into the reaction solution.

ACS Fall Meeting 2016 in Philadelphia: Yiren Wu

August 2016

Yiren represented the group to give two oral presenations on August 20th in the session of "Nanoparticles: Synthesis, Characterization & Their Application in Catalysis" (COLL 12) and "Plasmonic Colloidal Nanostructures: From Creation to Applications" (COLL 113). She also presented a poster.  

Publication in ACS Nano Article: Xiaojun Sun

July 2016

We report a facile synthesis of Au-based cubic nanoboxes as small as 20 nm for the outer edge length, together with well-defined openings at the corners and walls fewer than ten atomic layers (or <2 nm) in thickness. The resultant Au nanoboxes exhibit strong plasmonic absorption in the near-infrared region, consistent with computational simulations.

Publication in ChemNanoMat Communication: Jumei Li

April 2016

we report a dual catalyst based on Ag@Pd-Ag core-frame nanocubes for the stepwise conversion of 4-nitrothiophenol to trans-4,4’-dimercaptoazobezene under ambient conditions. Our in-situ surface-enhanced Raman spectroscopy study reveals three sequential processes that include the Pd-catalyzed reduction of 4-nitrothiophenol to 4-aminethiophenol by hydrogen, a period during which the 4-aminothiophenol remain unchanged until all hydrogen has depleted, and the Ag-catalyzed oxidation of 4-aminothiphenol to trans-4,4’-dimercaptoazobezene by the O2 from air.

Congratulations to Albert Ahn

April 2016

Jae Wan (Albert) Ahn received the 1st place award in the 4th Annual School of Materials Science and Engineering Undergraduate and Graduate Poster Session for his poster titled "Citrate-free Synthesis and Seed-mediated Growth of Silver Nanoplates," competing under the Graduate Pre-Qualifier category.

Publication in ChemNanoMat Communication (VIP): Jumei Li

March 2016

We report a facile synthesis of Ag-enriched Ag-Pd bimetallic nanoframes with ridges as thin as 1.7 nm. The synthesis leverages our recently developed co-titration methodology to co-deposit Ag and Pd atoms derived from the co-reduction of Na2PdCl4 and AgNO3 by ascorbic on the edge and corner sites of Ag nanocubes for the generation of Ag@Ag-Pd core-frame nanocubes. When subjected to H2O2 etching, the Ag cores are selectively removed to generate Ag-Pd bimetallic nanoframes made of ultrathin ridges enriched in Ag.

2016 MRS Spring Meeting, Phoenix

March 2016

Dr. Qin delivered her invited talk -- Bifunctional Nanocrystals for Monitoring the Catalytic Reactions by Surface-Enhanced Raman Spectroscopy.

2016 ACS Spring Meeting, San Diego

March 2016

Dr. Qin delivered her invited talk -- Bifunctional Nanocrystals for Monitoring the Catalytic Reactions by Surface-Enhanced Raman Spectroscopy -- in the colloidal division.

Lecture - Colubmia University, New York City

March 2016

Dr. Qin visited the MERSEC Center at Colubmia University and presented our work - Enriching Ag Nanocrystals with Au.

Lecture: Temple University, Philadelphia

March 2016

Dr. Qin visited the department of Chemistry at Temple University and presented our work - Enriching Ag Nanocrystals with Au.

Thanks for Being a Great Teacher

February 2016

In appreciation of her teaching style and dedication to helping students learn in MSE 4330 - Fundamentals of Nanomaterials and Nanostructures, Dr. Qin received a certificate from "Thank a Teacher Program" at Georgia Tech. The student acknowledged: "Thank you for making the difficult topic of nanotechnology interesting and accessible. You are definitely one of my favorite professors at Tech. Good luck with your research!"

Publication in ACS Nano Article: Jiawei Zhang

January 2016

We report a facile synthesis of Ag@Au concave cuboctahedra that embrace excellent SERS activity and chemical stability. These two unique attributes enable in-situ SERS monitoring of the reduction of 4-nitrothiophenol (4-NTP) to 4-aminothiophenol (4-ATP) by NaBH4 through a 4,4’-dimercaptoazobenzene (trans-DMAB) intermediate and the subsequent oxidation of 4-ATP back to trans-DMAB upon the introduction of H2O2.

Lecture: University of California, Riverside

January 2016

Dr. Qin visitied the department of Chemistry at UC-Riverside and presented our work -- Enriching Ag Nanocrystals with Au.

Happy Holidays and Best Wishes for 2016

December 2015

We celebrated our accomplishments of 2015 in the Qin Lab holiday dinner gathering. The team is full of talent to perform experiments in (the Qin) lab and to cook in (their own) kitchen!! Clockwise, the Qin Lab published **limited” edition of papers in 2015 with a positive outlook of 2016!

Congratulations to Dr. Jiawei Zhang

December 2015

Jiawei Zhang, the formal joint PhD student successfully completed his thesis defense at Xiamen University, Xiamen, China. He will continue his pose at Xiamen University as a postdoctoral fellow.

Siemens's Competition in Math, Science & Technology 2015

November 2015

Dr. Qin was the judge of Regional Finals at Georgia Institute of Technology. The Siemens Foundation has invested more than $90 million in the United States to advance workforce development and education initiatives in science, technology, engineering and math.

Grand Challenges at Georgia Tech

October 2015

Dr. Qin joined the Grand Challenges Faculty Fellows upon student nomination. Grand Challenges provides students with an opportunity to develop problem solving, analytical, and critical thinking skills in order to find solutions to real-world problems.

Publication in Journal of Materials Chemistry C Article - Xiaojun Sun

October 2015

We discovered that the added Ag+ ions could effectively push the galvanic replacement reaction between Ag nanocubes and HAuCl4 backward and thus inhibit it, making it possible to achieve the co-reduction of the two precursors by ascorbic acid without involving any galvanic replacement. This piece of work opens up a possibliblity to deposit Ag-Au alloys with controls in composition and morphology.

PhD Thesis Proposal - Xiaojun Sun

September 2015

Xiaojun successfully passed his thesis proposal on the 9th of September. Congratulations!!

Faces of Inclusive Excellence 2015

July 2015

Dr. Qin received the honor among a group of deserving faculty, staff, and students who distinguished themselves in their research, teaching, and/or service by receiving special awards or recognitions for their work during the academic year (2014-15) at Georgia Tech.

Publication in JACS Communication - Jumei Li

May 2015

We report a route to the facile synthesis of Ag@Pd-Ag nanocubes for for in situ SERS monitoring of the Pd-catalyzed reduction of 4-nitrothiophenol by NaBH4. This piece of work was also received the best poster award in the 2015 MRS Spring meeting.

2015 MRS Spring Meeting, San Francisco

April 2015

The Qin Lab presented one invited talk and six posters at the conference. Dr. Jumei Li won the best poster award.

Lecture: University of Florida

March 2015

Dr. Qin visitied the department of Chemistry at University of Florida and presented our work -- Enriching Ag Nanocrystals with Au.

CTEL/BP Junior Faculty Teaching Excellence Award

March 2015

Dr. Qin is the recipient of 2015 GT-CTEL/BP Junior Faculty Teaching Excellence Award to recognize her dedication to play a role as an effective teacher.

3M NON-TENURED FACULTY AWARD

March 2015

Dr. Qin received 3M non-tenured faculty award for our work on oxidative-free bimetallic nanoplates for printable electronics.

Lecture: Georgia Tech

December 2014

Dr. Qin presented our work-Enriching Ag Nanocrystals with Au-at Nano@Tech sponsored by the Institute for Electronics and Nanotechnology (IEN) at Georgia Tech.

Publication in Langmuir - Jiawei Zhang

December 2014

We demonstrated the use of citrate-free Ag nanoplates for the vertical growth into truncated bipyramids and twinned cubes by manipulating the amount of Cl- ions in the reaction solution. 

Congratulations to Dr. Yin Yang

December, 2014

Yin Yang, the formal joint PhD student successfully defended his PhD at Fudan University, Shanghai China. He will shortaly join Jean-Marie Tarascon at College-de-France soon.
 

Lecture: University of Washington

November 2014

Dr. Qin visited MSE at University of Washington in Seattle and presented our work - Ag-Au Nanocubes with Enhanced SERS and Chemical Stability.

Publication in Journal of Materials Chemistry C - Jumei Li

September 2014

We demonstrated the use of Ag-Au hollow nanocubes for SERS detection of melamine at 10^-8 M -- a concentration much lower than the tolerance level of 1 ppm in infant formula.
 

An NSF Award 2014-2017

August 2014

We recevied an NSF award from the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry to develop a scientific basis for achieving seeded growth with two metals that have been plagued by galvanic replacement reactions. 
 

GT-PURA - Albert Ahn

June 2014

Abert Ahn, the senior of GT-MSE, has been selected as a recipient of the Georgia Tech President's Undergraduate Research Award (PURA) for Fall 2014.
 

Publication in JACS Communication - Yin Yang

May 2014

We demonstrated a strategy for depositing uniform, conformal shells of Au on the surfaces of Ag nanocubes to generate Ag@Au core-shell nanocubes with enhanced chemical stability and SERS activity.

No Small Matter - 见微知著

May 2014

The book - "No Small Matter - Science on the Nanoscale" - by Felice C. Frankel and George M. Whitesides has been transformed into a bilingual book by the USTC Press in China.  The Qin lab made our original contributions to translation, chinese title, and cover design. Ths book has hit the Chinese marketplace.  

MRS San Franscisco, 2014

April 2014

Dr. Qin and Yin presented our work on Ag-Au nanocubes and Ag nanoplates at the conference.

Nano@Tech Presentation - Yin Yang

April 2014

Yin Yang presented our work - "Selective Deposition of Au onto 40-nm Ag Nanocubes with Excellent Plasmonic Properties and Chemical Stability" - at Nano@Tech sponsored by the Institute for Electronics and Nanotechnology (IEN) at Georgia Tech.
 

2014 ACS Spring Meeting in Dallas

March 2014

Dr. Qin presented one invited and three talks at ACS spring meeting in Dallas. The subject covers from the Ag nanoplates to Au coated Ag nanocubes with their unique plasmonic properties. 
 

Publication in ACS Applied Matertials & Interfaces - Yin Yang

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We developed a new class of Ag-Au nanoboxes with enrichment of Ag to greatly SERS properties and chemical stability. This piece of work has been accepted as a full article in ACS Applied Materials & Inferfaces.
 

An Award from Agnes Scott College

September 2013