A novel non-fullerene electron acceptor (ITIC) that overcomes some of the shortcomings of fullerene acceptors, for example, weak absorption in the visible spectral region and limited energy-level variability, is designed and synthesized. Fullerene-free polymer solar cells (PSCs) based on the ITIC acceptor are demonstrated to exhibit power conversion effi ciencies of up to 6.8%, a record for fullerene-free PSCs.

An electron acceptor challenging fullerenes for efficient polymer solar cells.

Although the field of polymer solar cell has seen much progress in device performance in the past few years, several limitations are holding back its further development For instance, current high-efficiency (>90%) cells are restricted to material combinations that are based on limited donor polymers and only one specific fullerene acceptor Here we report the achievement of high-performance (efficiencies up to 108%, fill factors up to 77%) thick-film polymer solar cells for multiple polymer:fullerene combinations via the formation of a near-ideal polymer:fullerene morphology that contains highly crystalline yet reasonably small polymer domains This morphology is controlled by the temperature-dependent aggregation behaviour of the donor polymers and is insensitive to the choice of fullerenes The uncovered aggregation and design rules yield three high-efficiency (>10%) donor polymers and will allow further synthetic advances and matching of both the polymer and fullerene materials, potentially leading to significantly improved performance and increased design flexibility

/pdf/aggregation-and-morphology-control-enables-multiple-cases-of-37iznlawg4.pdf

Aggregation and morphology control enables multiple cases of high-efficiency polymer solar cells.

An effective way to improve polymer solar cell efficiency is to use a tandem structure, as a broader part of the spectrum of solar radiation is used and the thermalization loss of photon energy is minimized. In the past, the lack of high-performance low-bandgap polymers was the major limiting factor for achieving high-performance tandem solar cell. Here we report the development of a high-performance low bandgap polymer (bandgap 60% and spectral response that extends to 900 nm, with a power conversion efficiency of 7.9%. The polymer enables a solution processed tandem solar cell with certified 10.6% power conversion efficiency under standard reporting conditions (25 °C, 1,000 Wm(-2), IEC 60904-3 global), which is the first certified polymer solar cell efficiency over 10%.

/pdf/a-polymer-tandem-solar-cell-with-10-6-power-conversion-4c0mv7dgja.pdf

A polymer tandem solar cell with 10.6% power conversion efficiency

Recent Advances in Bulk Heterojunction Polymer Solar Cells

Although organic photovoltaic (OPV) cells have many advantages, their performance still lags far behind that of other photovoltaic platforms. A fundamental reason for their low performance is the low charge mobility of organic materials, leading to a limit on the active-layer thickness and efficient light absorption. In this work, guided by a semi-empirical model analysis and using the tandem cell strategy to overcome such issues, and taking advantage of the high diversity and easily tunable band structure of organic materials, a record and certified 17.29% power conversion efficiency for a two-terminal monolithic solution-processed tandem OPV is achieved.

https://science.sciencemag.org/content/sci/early/2018/08/08/science.aat2612.full.pdf

Organic and solution-processed tandem solar cells with 17.3% efficiency

A composition comprising a first compound having a structure represented by formula (1), and a second compound composed of only a structure different from the structure represented by formula (1).

Composition and device using same

La presente invention a trait a un element de conversion photoelectrique utile qui est dote d'une tension de circuit ouvert elevee. Ledit element de conversion photoelectrique est pourvu d'une premiere electrode, d'une seconde electrode et d'une couche active entre lesdites premiere et seconde electrodes. Ladite couche active contient un compose organique contenant un motif structural represente par la formule (1). (Dans la formule, R 1 represente un atome d'hydrogene, un atome d'halogene, un groupe alkyle, un groupe alcoxy, un groupe alkylthio, un groupe aryle, un groupe aryloxy, un groupe arylthio, un groupe aryle alkyle, un groupe aryle alcoxy, un groupe aryle alkylthio, un groupe aryle alcenyle, un groupe aryle alcynyle, un groupe amino, un groupe amino substitue, un groupe silyle, un groupe silyle substitue, un groupe silyloxy, un groupe silyloxy substitue, un groupe heterocyclique, un groupe acyle, un groupe acyloxy, un groupe amide, un groupe carboxyle, un groupe nitro ou un groupe cyano ; et chacun des noyaux D et E represente independamment un noyau aromatique qui peut avoir un substituant.)

Élément de conversion photoélectrique

The present invention provides, as an electrolyte which is useful as a material for a proton conductive membrane in a solid polymer fuel cell utilizing a gas fuel such as hydrogen gas or a liquid fuel such as methanol or dimethyl ether and which has higher proton conductivity than the conventional electrolytes do, an electrolyte characterized by containing an oxocarbon molecule, wherein the oxocarbon molecule has a difference in heat of formation ”E defined as: ”E = E 2 -E 1 (kcal/mol) satisfying the range of: ”E<-70 (kcal/mol), wherein E 1 (kcal/mol) is a heat of formation in the state where a hydrogen ion is non-dissociated, and E 2 (kcal/mol) is a heat of formation in the state where a hydrogen having the lowest dissociation energy in the molecule ion is dissociated, both being calculated in regard to the stabilized molecular structure in accordance with a molecular orbital method

Electrolyte containing oxocarbonic acid and its use

A compound which has a structural unit represented by formula (1) and a structural unit represented by formula (2). (In the formulae, X 1 , X 2 , X 3 and X 4 may be the same as or different from each other, and each represents a nitrogen atom or =CH-; Y 1 and Y 2 may be the same as or different from each other, and each represents a sulfur atom, an oxygen atom, a selenium atom, -N(R 1 )- or -CR 2 =CR 3 -; R 1 , R 2 and R 3 may be the same as or different from each other, and each represents a hydrogen atom, a halogen atom, an amino group, a cyano group or a monovalent organic group; W 1 and W 3 may be the same as or different from each other, and each represents a halogen atom, a cyano group or a monovalent organic group; and W 2 and W 4 may be the same as or different from each other, and each represents a hydrogen atom, a halogen atom, a cyano group or a monovalent organic group. In this connection, the a structural unit represented by formula (1) and the structural unit represented by formula (2) are not the same as each other.)

Compound and electronic element

A compound which contains a structure represented by formula (1) and has a light absorption end wavelength of 600 nm or more.

Ken Yoshimura

Papers

Composition and device using same

Élément de conversion photoélectrique

Electrolyte containing oxocarbonic acid and its use

Compound and electronic element

Compound and device using same