scholarly journals Supramolecular Approaches for Taming the Chemo- and Regiochemistry of C60 Addition Reactions

2021 ◽  
Vol 03 (02) ◽  
pp. 146-154
Author(s):  
Sebastian B. Beil ◽  
Max von Delius

The chemo- and regioselective functionalization of fullerenes is a long-standing problem of organic synthesis. Over the past five years, this fundamental challenge has gained technological relevance, because studies on single bis-adduct isomers in new-generation solar cells have demonstrated that the widespread use of isomer mixtures leads to suboptimal power conversion efficiencies. Herein, we review recent work on supramolecular approaches for achieving chemo- and regioselective syntheses of multiply functionalized derivatives of C60.

Nanoscale ◽  
2021 ◽  
Author(s):  
Congcong Zhao ◽  
Jiuxing Wang ◽  
Xuanyi Zhao ◽  
Zhonglin Du ◽  
Renqiang Yang ◽  
...  

The past decade has seen a tremendous development of organic solar cells (OSCs). To date, the high-performance OSCs have boosted the power conversion efficiencies (PCEs) over 17%, showing bright prospects...


2021 ◽  
Author(s):  
Haifen Liu ◽  
Zixuan Zhu ◽  
Huafeng Li ◽  
Weili Fan ◽  
Kaihua Ning ◽  
...  

Non-fullerene acceptors have received a great deal of attention over the past several years, and numerous modifications on the molecular structures significantly boosted the power conversion efficiencies (PCEs). To be...


Author(s):  
Syed Ossama Ali Ahmad ◽  
Atif Ashfaq ◽  
Muhammad Usama Akbar ◽  
Mujtaba Ikram ◽  
Karim Khan ◽  
...  

Perovskite solar cells (per-SCs) with high performance and cost-effective solution processing have been the center of interest for researchers in the past decade. Power conversion efficiencies (PCEs) have been gradually...


Synthesis ◽  
2021 ◽  
Author(s):  
Boris Trofimov ◽  
Anastasiya Mal’kina

Cyanoacetylenic alcohols, R1R2C(OH)C≡C-CN, the closest derivatives of cyanoacetylene, an interstellar abundant molecule, are now becoming acknowledgeable in modern organic synthesis which tends to mimic nature. Highly reactive C≡C and C≡N bonds in close vicinity of the hydroxyl group makes these molecules a chemical trinity of mutually influencing functions ensuring an endless number of chemical transformations. All reactions of cyanoacetylenic alcohols parallel modern organic synthesis, being biomimetic. They do not need transition metals (and in most cases, the metals at all except for physiologically indispensible Na+, K+), proceed at ambient temperature and often in aqueous media. Fundamentally, these reactions are 100% atom-economic because they are almost exclusively addition processes. Usually, in the cyanoacetylenic alcohols, cyano, acetylene and hydroxyl functions behave as inseparable entity providing the multiple functionalizations of the forming molecules. This allows hydroxyl, carbonyl, carboxylic, imino, amino, amido, cyanoamido, cyano, various P-containing, ether and ester functions, along with the double bonds and different fundamental heterocycles (furans, furanones, pyrazoles, oxazoles, pyridines, pyrimidines, purins, etc.) and diverse polycyclic systems to be integrated in a one molecular architecture. This review focuses on analysis and generalization of the knowledge accumulated in the chemistry of these cyanoacetylenic alcohols, mostly over the past 15 years.


2015 ◽  
Vol 5 (5) ◽  
pp. 2554-2574 ◽  
Author(s):  
Xiao-Yun Dong ◽  
Zi-Wei Gao ◽  
Ke-Fang Yang ◽  
Wei-Qiang Zhang ◽  
Li-Wen Xu

Silver nanoparticles catalysis has been of great interest in organic synthesis and has expanded rapidly in the past ten years because of nanosilver catalysts' unique reactivity and selectivity, stability, as well as recyclability in catalytic reactions.


2017 ◽  
Vol 5 (23) ◽  
pp. 11436-11449 ◽  
Author(s):  
Hang Hu ◽  
Binghai Dong ◽  
Wei Zhang

Over the past few years, lead halide perovskites have emerged as a class of dominant semiconductor materials in the photovoltaic (PV) field with an unprecedented sharp enhancement of power conversion efficiencies (PCEs) up to 22.1%, as well as in other promising optoelectronic applications due to their extraordinary and unique properties.


2020 ◽  
Vol 8 (15) ◽  
pp. 7083-7089 ◽  
Author(s):  
Kai Chen ◽  
Ruijie Ma ◽  
Tao Liu ◽  
Zhenghui Luo ◽  
Xiaopeng Xu ◽  
...  

Over the past decade, fluorinated materials have become the dominant donors for achieving high power conversion efficiencies in organic solar cells (OSCs).


Author(s):  
John L. Hutchison

Over the past five years or so the development of a new generation of high resolution electron microscopes operating routinely in the 300-400 kilovolt range has produced a dramatic increase in resolution, to around 1.6 Å for “structure resolution” and approaching 1.2 Å for information limits. With a large number of such instruments now in operation it is timely to assess their impact in the various areas of materials science where they are now being used. Are they falling short of the early expectations? Generally, the manufacturers’ claims regarding resolution are being met, but one unexpected factor which has emerged is the extreme sensitivity of these instruments to both floor-borne and acoustic vibrations. Successful measures to counteract these disturbances may require the use of special anti-vibration blocks, or even simple oil-filled dampers together with springs, with heavy curtaining around the microscope room to reduce noise levels. In assessing performance levels, optical diffraction analysis is becoming the accepted method, with rotational averaging useful for obtaining a good measure of information limits. It is worth noting here that microscope alignment becomes very critical for the highest resolution.In attempting an appraisal of the contributions of intermediate voltage HREMs to materials science we will outline a few of the areas where they are most widely used. These include semiconductors, oxides, and small metal particles, in addition to metals and minerals.


2020 ◽  
Vol 8 (43) ◽  
pp. 15135-15141
Author(s):  
Jing Yan ◽  
Yuan-Qiu-Qiang Yi ◽  
Jianqi Zhang ◽  
Huanran Feng ◽  
Yanfeng Ma ◽  
...  

Two non-fullerene small molecule acceptors, NT-4F and NT-4Cl, were designed and synthesized. Power conversion efficiencies of 11.44% and 14.55% were achieved for NT-4Cl-based binary and ternary devices, respectively.


2020 ◽  
Author(s):  
Lungwani Muungo

The purpose of this review is to evaluate progress inmolecular epidemiology over the past 24 years in canceretiology and prevention to draw lessons for futureresearch incorporating the new generation of biomarkers.Molecular epidemiology was introduced inthe study of cancer in the early 1980s, with theexpectation that it would help overcome some majorlimitations of epidemiology and facilitate cancerprevention. The expectation was that biomarkerswould improve exposure assessment, document earlychanges preceding disease, and identify subgroupsin the population with greater susceptibility to cancer,thereby increasing the ability of epidemiologic studiesto identify causes and elucidate mechanisms incarcinogenesis. The first generation of biomarkers hasindeed contributed to our understanding of riskandsusceptibility related largely to genotoxic carcinogens.Consequently, interventions and policy changes havebeen mounted to reduce riskfrom several importantenvironmental carcinogens. Several new and promisingbiomarkers are now becoming available for epidemiologicstudies, thanks to the development of highthroughputtechnologies and theoretical advances inbiology. These include toxicogenomics, alterations ingene methylation and gene expression, proteomics, andmetabonomics, which allow large-scale studies, includingdiscovery-oriented as well as hypothesis-testinginvestigations. However, most of these newer biomarkershave not been adequately validated, and theirrole in the causal paradigm is not clear. There is a needfor their systematic validation using principles andcriteria established over the past several decades inmolecular cancer epidemiology.


Sign in / Sign up

Export Citation Format

Share Document