143 research outputs found
Chemical Synthesis and Materials Discovery
Functional materials impact every area of our lives ranging from electronic
and computing devices to transportation and health. In this Perspective, we
examine the relationship between synthetic discoveries and the scientific
breakthroughs that they have enabled. By tracing the development of some
important examples, we explore how and why the materials were initially
synthesized and how their utility was subsequently recognised. Three common
pathways to materials breakthroughs are identified. In a small number of cases,
such as the aluminosilicate zeolite catalyst ZSM-5, an important advance is
made by using design principles based upon earlier work. There are also rare
cases of breakthroughs that are serendipitous, such as the buckyball and
Teflon(R). Most commonly, however, the breakthrough repurposes a compound that
is already known and was often made out of curiosity or for a different
application. Typically, the synthetic discovery precedes the discovery of
functionality by many decades; key examples include conducting polymers,
topological insulators and electrodes for lithium-ion batteries.Comment: 15 pages, two figure
Well-defined donor-acceptor rod-coil diblock copolymers based on P3HT containing C-60: the morphology and role as a surfactant in bulk-heterojunction solar cells
The synthesis of well-defined rod-coil block copolymers consisting of P3HT donor and C-60 acceptor chromophores (P3HT-b-P(S(x)A(y))-C-60) in a molecular architecture is reported for use in bulk-heterojunction (BHJ) solar cells. In thin films of the resulting block copolymer, reproducible self-assembly into well-defined "nanofibrils'' is observed. This is the first example of a block copolymer containing a C-60 derivative that shows exclusively a nanofibrilar structure. We have investigated the potential utility of the block copolymer as a "surfactant'' for controlling the interface morphology of the P3HT: PCBM donor-acceptor phase domains within the composite. We find a substantial improvement in device performance when 5% of block copolymer are introduced to the P3HT: PCBM blend system, resulting in ca. 35% improved efficiency relative to the P3HT: PCBM solar cell fabricated without the "surfactant''.close13212
Photochemical Response of Electronically Reconfigurable Molecule-Based Switching Tunnel Junctions
Robust molecular devices may be based on the photo‐switching between spiropyran and merocyanine isomers (see Scheme). The equilibrium has been investigated in a Langmuir–Blodgett film and then succesfully sandwiched into a solid‐state tunnel junction
Electrochemical Characterization of Films of Single-Walled Carbon Nanotubes and Their Possible Application in Supercapacitors
Films of single-wall carbon nanotubes (SWCNTs) were cast from suspensions in several solvents on the surface of a Pt or Au electrode. Cyclic voltammetry of the films in MeCN did not show well-resolved waves (as distinct from films of C_(60) prepared in a similar manner). However, the increase in the effective capacitance of the electrode with a SWCNT film at 0.5 V vs. an AgQRE was 283 F/g, which is about twice that of carbon electrodes in nonaqueous solvents
A synthetic approach to a fullerene-rich dendron and its linear polymer via ring-opening metathesis polymerization
Through the esterification of an acyl chloride functionalized fullerene precursor with dendritic alcohol, a fullerene-rich dendron containing a norbornene unit at the focal point is prepared for ring-opening metathesis polymerization to obtain its linear polymer with a unimodal and narrow molar mass distribution (PDI = 1.08) by a progressive addition of catalysts.close181
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