PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Tiny tweaks to sparkle: Editing light-emitting organic molecules via surface modification

Researchers develop a strategy that allows a single family of polymeric materials to emit light in any of the three primary colors

Tiny tweaks to sparkle: Editing light-emitting organic molecules via surface modification
2021-07-06
(Press-News.org) Ishikawa, Japan - Many researchers in the field of materials science constantly seek novel and versatile platforms that can be used to tailor materials to match their intended use. One example of this are covalent organic frameworks (COFs), an emerging class of crystalline porous polymers with a favorable set of fundamental properties, namely crystallinity, stability, and porosity. This combination makes them, in theory, adjustable to many modern applications. Unfortunately, owing to the way COFs are usually obtained, these properties are not very pronounced, resulting in unstable, low-crystallinity solids with limited porosity.

At the Japan Advanced Institute of Science and Technology, Dr. Zhongping Li, Associate Professor Yuki Nagao, and colleagues are trying to put an end to this issue and showcase the true potential of COFs. In their latest study, which was published in Angewandte Chemie International Edition as Very Important Paper, Dr. Nagao, Professor Donglin Jiang at the National University of Singapore, and his team devised a novel strategy for easily tuning the light-emitting properties of hydrazone-linked COFs to produce red, green, or blue (RGB) light by using a single material. This work was the result of a lot of efforts by many researchers including first-author Zhongping Li, Keyu Geng, Ting He, Ke Tian Tan, Ning Huang, Qiuhong Jiang, and Donglin Jiang at the National University of Singapore.

The researchers had been exploring a new concept that involves introducing atoms or small molecular groups into the pore walls of COFs. Though the changes in composition are relatively minor, the orderly introduction of these groups in surface sites causes drastic effects in the electronic structure of the entire molecule, altering some of its physicochemical properties. Without really expecting it, the researchers found that the small perturbations introduced in single surface sites greatly modified the light-emission characteristics of hydrazone-linked COFs.

More specifically, by introducing hydrogen, chlorine, methoxy, methyl, or hydroxy surface sites on the pore walls of COFs (see Figure 1), the team produced compounds that could be fine-tuned to emit light at various distinct frequencies within the RGB spectrum. Surprisingly, these COFs are among the few known material frameworks that can be easily tailored to emit any one of the three primary colors, and even colors in-between (see Figure 2). This is in stark contrast to most available RGB technologies, which require different materials to produce the three primary colors. "Thanks to the exciting features we observed, COF-based materials offer a solution to the low tunability problems found in organic/polymeric light-emitting materials," remarks Dr. Li, "By introducing perturbations with multiple wall surface sites, our frameworks can be used to edit the light-emission of materials to achieve any given color in a pre-designable and digital way."

Importantly, aside from these useful color tunability properties, the synthesized COFs were also up there in terms of luminescence, stability, and sensitivity to guest molecules. This combination of features makes the proposed framework especially attractive for light-emitting and sensing implementations using organic and polymeric materials, as well as for other types of applications, as Dr. Li explains: "Our perturbation strategy of introducing single atoms or small groups to induce electronic effects is compatible with further functionalization and should be widely applicable to other types of COFs."

It's possible that the strategy devices in this study will shape a new regime in light-emitting organic materials, which shall be useful for highly sophisticated applications and daily-life devices alike. Further refinement of similar methods will let us truly harness the power that even small, yet rational changes can have in the macroscopic behavior of certain materials.

INFORMATION:

Reference Title of original paper: "Editing Light Emission with Stable Crystalline Covalent Organic Frameworks via Wall Surface Perturbation" Journal: Angewandte Chemie International Edition DOI: 10.1002/anie.202107179 Funding information: This work is supported by an MOE tier 1 grant (R-143-000-A71-114) and a NUS start-up grant (R-143-000-A28-133).

About Japan Advanced Institute of Science and Technology, Japan Founded in 1990 in Ishikawa prefecture, the Japan Advanced Institute of Science and Technology (JAIST) was the first independent national graduate school in Japan. Now, after 30 years of steady progress, JAIST has become one of Japan's top-ranking universities. JAIST counts with multiple satellite campuses and strives to foster capable leaders with a state-of-the-art education system where diversity is key; about 40% of its alumni are international students. The university has a unique style of graduate education based on a carefully designed coursework-oriented curriculum to ensure that its students have a solid foundation on which to carry out cutting-edge research. JAIST also works closely both with local and overseas communities by promoting industry-academia collaborative research.

About Associate Professor Yuki Nagao from Japan Advanced Institute of Science and Technology, Japan Dr. Yuki Nagao is an Associate Professor at the Japan Advanced Institute of Science and Technology, Japan since 2012. He obtained his B.S. and M.S. from University of Tsukuba, Japan in 2001 and 2003, respectively and his Ph.D. from Kyushu University, Japan in 2006. He specializes in designing polymer materials conducive to interface proton transport with a focus on developing proton batteries and fuel cells. He has published over 100 papers with over 1400 citations to his credit. For more information about his research, visit: https://www.jaist.ac.jp/english/areas/mc/laboratory/nagao.html


[Attachments] See images for this press release:
Tiny tweaks to sparkle: Editing light-emitting organic molecules via surface modification

ELSE PRESS RELEASES FROM THIS DATE:

Scientists synthesize 3D graphene films with high-energy E-beam

Scientists synthesize 3D graphene films with high-energy E-beam
2021-07-06
Recently, Prof. WANG Zhenyang's research group from the Hefei Institutes of Physical Science (HFIPS) of the Chinese Academy of Sciences (CAS) has prepared macroscopic thick three-dimensional (3D) porous graphene films. Using high-energy electron beam as the energy source and taking advantages of high kinetic energy and low reflection characteristics of e-beam, the researchers directly induced polyimide precursor into a 3D porous graphene crystal film with a thickness of up to 0.66 mm. Related research results were published in the journal Carbon. Graphene has been proved ...

New nanotech will enable a 'healthy' electric current production inside the human body

New nanotech will enable a healthy electric current production inside the human body
2021-07-06
A new nanotechnology development by an international research team led by Tel Aviv University researchers will make it possible to generate electric currents and voltage within the human body through the activation of various organs (mechanical force). The researchers explain that the development involves a new and very strong biological material, similar to collagen, which is non-toxic and causes no harm to the body's tissues. The researchers believe that this new nanotechnology has many potential applications in medicine, including harvesting clean energy to operate devices implanted ...

Nano-scale borate bioactive glass: Next generation material for skin-healing

Nano-scale borate bioactive glass: Next generation material for skin-healing
2021-07-06
Recently, with the help of a steady-state strong magnetic field experimental device, scientists constructed nano-scale borate bioactive glass (Nano-HCA@BG), which can effectively reduce the biological toxicity of borate bioglass, improve the biocompatibility of the glass, and promote the effect of borate bioglass on skin repair. Prof. WANG Junfeng from the Hefei Institutes of Physical Science (HFIPS) of the Chinese Academy of Sciences (CAS), collaborating with Prof. ZHANG Teng from Fuzhou University in this study, said, "it is expected to become the next generation of skin wound repair dressings." Related research was published in Chemical Engineering Journal. Borate bioglass is a glass with boron element (B) as the glass network matrix. With good dopability and degradability, it ...

New warning on teen sleep

New warning on teen sleep
2021-07-06
Sleep deprivation - from lifestyle choices, pandemic stress, or late-night computer study - can quickly lead to loss of energy and function during the day and even feelings of anger and depression, an Australian sleep institute study has shown. The study, led by Flinders University, asked 34 health teenagers (20 males) aged between 15 and 17 to spent 10 days and nine nights in a specially designed sleep centre. They were allocated to one of three sleep 'doses' for five consecutive nights- from five hours, 7.5 hours, or 10 hours in bed per night - with two baseline and two 'recovery' nights of up to 10 hours' time in bed. Their mood was measured every three hours after waking up to assess responses to feelings such as 'depressed', 'afraid', 'angry', 'confused', ...

Aboveground biomass and its spatial distribution pattern of herbaceous marsh vegetation in China

Aboveground biomass and its spatial distribution pattern of herbaceous marsh vegetation in China
2021-07-06
Wetland, forest, and ocean are the three largest ecosystems in the world. Although the area of wetland ecosystem accounts for only 4-6% of the total land area, the carbon reserves of wetland ecosystem accounts for 12-24% of the global land carbon reserves. Under the background of global climate change, the research on carbon sequestration of wetland has become an important subject of global carbon cycle research. The area of marshes in China ranks third in the world, and herbaceous marsh is the most widely distributed among all the types of marshes. As an important quality parameter of marsh ecosystem, aboveground biomass of vegetation is a crucial index estimating the carbon storage of marsh vegetation, and the basis for studying ...

Study of T cells from COVID-19 convalescents guides vaccine strategies?

Study of T cells from COVID-19 convalescents guides vaccine strategies?
2021-07-06
A KAIST immunology research team found that most convalescent patients of COVID-19 develop and maintain T cell memory for over 10 months regardless of the severity of their symptoms. In addition, memory T cells proliferate rapidly after encountering their cognate antigen and accomplish their multifunctional roles. This study provides new insights for effective vaccine strategies against COVID-19, considering the self-renewal capacity and multipotency of memory T cells. COVID-19 is a disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. When patients recover from COVID-19, SARS-CoV-2-specific adaptive immune memory is developed. The adaptive immune system consists ...

Snap, crackle, pop: Bone marrow-derived fibrin clot as better source for meniscal repair

Snap, crackle, pop: Bone marrow-derived fibrin clot as better source for meniscal repair
2021-07-06
While this isn't the fountain of youth, scientists may have improved healing in our joints - even in areas that become weaker as we grow older. The meniscus is a durable, yet flexible tissue found in joints like our wrist and knees that helps them absorb shock during movement. Occasionally tears can occur in the meniscus due an awkward movement or structural weakness from old age. When we are young, there is plenty of blood flowing to this area allowing for quick healing, but as we get older, the meniscus receives less and less blood - with the inner most area becoming ...

Modelling COVID-19 cases in Africa

Modelling COVID-19 cases in Africa
2021-07-06
An international team including Lancaster University researchers has created a strategy for understanding the evolution of the COVID-19 pandemic throughout the African continent. Their COVID-19 surveillance strategy will improve the ability of African countries to interpret the complex data available to them during the pandemic. Professor Peter Diggle, Dr Chris Jewell and Dr Claudio Fronterre from the Centre for Health Informatics, Computing and Statistics (CHICAS) at Lancaster Medical School worked with colleagues in the USA, Uganda and Switzerland to create a data-driven disease surveillance framework to track and predict ...

Comprehensive genetic study of cleft lip and palate

Comprehensive genetic study of cleft lip and palate
2021-07-06
Cleft lip and palate is one of the most common congenital malformations. Its causes are mainly genetic. However, it is still largely unknown exactly which genes are affected. A new international study led by the University of Bonn now provides new insights. The results are published in the journal Human Genetics and Genomics Advances, but are already available online. The researchers from the Institute of Human Genetics at the University Hospital Bonn combined various data sources in their work. In the course of their research, they discovered five new regions in the human genome in which variations in the DNA sequence are associated with an ...

New report aims to improve VR use in healthcare education

New report aims to improve VR use in healthcare education
2021-07-06
A new report that could help improve how immersive technologies such as Virtual Reality (VR) and Augmented Reality (AR) are used in healthcare education and training has been published with significant input from the University of Huddersfield. Professor David Peebles, Director of the University's Centre for Cognition and Neuroscience, and Huddersfield PhD graduate Matthew Pears contributed to the report - 'Immersive technologies in healthcare training and education: Three principles for progress' - recently published by the University of Leeds with input from range of academics, technologists and health professionals. The principles have also been expanded upon in a letter to the prestigious journal BMJ ...

LAST 30 PRESS RELEASES:

Shaking it up: An innovative method for culturing microbes in static liquid medium

Greener and cleaner: Yeast-green algae mix improves water treatment

Acquired immune thrombotic thrombocytopenic purpura (TTP) associated with inactivated COVID-19 vaccine CoronaVac

CIDEC as a novel player in abdominal aortic aneurysm formation

Artificial intelligence: a double-edged sword for the environment?

Current test accommodations for students with blindness do not fully address their needs

Wide-incident-angle wideband radio-wave absorbers boost 5G and beyond 5G applications

A graph transformer with boundary-aware attention for semantic segmentation

C-Path announces key leadership appointments in neurodegenerative disease research

First-of-its-kind analysis of U.S. national data reveals significant disparities in individual well-being as measured by lifespan, education, and income

Exercise programs help cut new mums’ ‘baby blues’ severity and major depression risk

Gut microbiome changes linked to onset of clinically evident rheumatoid arthritis

Signals from the gut could transform rheumatoid arthritis treatment

Pioneering research reveals some of the world’s least polluting populations are at much greater risk of flooding fuelled by climate change

UK’s health data should be recognized as critical national infrastructure, says independent review

A 36-gene predictive score of anti-cancer drug resistance anticipates cancer therapy outcomes

Someone flirts with your spouse. Does that make your partner appear more attractive?

Hourglass-shaped stent could ease severe chest pain from microvascular disease

United Nations ratifies framework to protect people on cash app

Oklahoma State basketball team joins the Nation of Lifesavers

Power of aesthetic species on social media boosts wildlife conservation efforts, say experts

Researchers develop robotic sensory cilia that monitor internal biomarkers to detect and assess airway diseases

Could crowdsourcing hold the key to early wildfire detection?

Reconstruction of historical seasonal influenza patterns and individual lifetime infection histories in humans based on antibody profiles

New study traces impact of COVID-19 pandemic on global movement and evolution of seasonal flu

Presenting a Janus channel of membranes for complete oil-and-water separation

COVID-19 restrictions altered global dispersal of influenza viruses

Disconnecting hepatic vagus nerve restores balance to liver and brain circadian clocks, reducing overeating in mice

Mechanosensory origins of “wet dog shakes” – a tactic used by many hairy mammals – uncovered in mice

New study links liver-brain communication to daily eating patterns

[Press-News.org] Tiny tweaks to sparkle: Editing light-emitting organic molecules via surface modification
Researchers develop a strategy that allows a single family of polymeric materials to emit light in any of the three primary colors