Changduk Yang

Further improvement and stabilization of perovskite solar cell (PSC) performance are essential to achieve the commercial viability of next-generation photovoltaics. Considering the benefits of fluorination to conjugated materials for energy levels, hydrophobicity, and noncovalent interactions, two fluorinated isomeric analogs of the well-known hole-transporting material (HTM) Spiro-OMeTAD are developed and used as HTMs in PSCs. The structure-property relationship induced by constitutional isomer

By considering the qualitative benefits associated with solution rheology and mechanical properties of polymer semiconductors, it is expected that polymer-based electronic devices will soon enter our daily lives as indispensable elements in a myriad of flexible and ultra low-cost flat panel displays. Despite more than a decade of research focused on designing and synthesizing state-of-the-art polymer semiconductors for improving charge transport characteristics, the current mobility values are s

Ambipolar polymer semiconductors are highly suited for use in flexible, printable, and large-area electronics as they exhibit both n-type (electron-transporting) and p-type (hole-transporting) operations within a single layer. This allows for cost-effective fabrication of complementary circuits with high noise immunity and operational stability. Currently, the performance of ambipolar polymer semiconductors lags behind that of their unipolar counterparts. Here, we report on the side-chain engine

There is a fast-growing demand for polymer-based ambipolar thin-film transistors (TFTs), in which both n-type and p-type transistor operations are realized in a single layer, while maintaining simplicity in processing. Research progress toward this end is essentially fueled by molecular engineering of the conjugated backbones of the polymers and the development of process architectures for device fabrication, which has recently led to hole and electron mobilities of more than 1.0 cm(2) V(-1) s(-

A record breaking PCE of 12.1% is achieved by incorporating 25 wt% of DR3TSBDT into a PTB7-Th:PC₇₁BM host matrix.

The synthesis of two well-solubilized [60]methanofullerene derivatives ( p- EHO-PCBM and p- EHO-PCBA) is presented for usage in organic solar cells and in field-effect transistors. The para position of the PCBM's phenyl ring was substituted with a branched alkoxy side chain, which contributes to higher solubility, facilitating synthesis, purification, and processing. We find a small change of the open-circuit voltage ( V oc) as a slight improvement in performance upon application in P3HT/[60]met

Considering the potential applications of all-polymer solar cells (all-PSCs) as wearable power generators, there is an urgent need to develop photoactive layers that possess intrinsic mechanical endurance, while maintaining a high power-conversion efficiency (PCE).Herein a strategy is demonstrated to simultaneously control the intercalation behavior and nanocrystallite size in the polymer-polymer blend by using a newly developed, high-viscosity polymeric additive, poly(dimethylsiloxane-co-methyl

Abstract Flexible and stretchable organic solar cells (OSCs) have attracted enormous attention due to their potential applications in wearable and portable devices. To achieve flexibility and stretchability, many efforts have been made with regard to mechanically robust electrodes, interface layers, and photoactive semiconductors. This has greatly improved the performance of the devices. State‐of‐the‐art flexible and stretchable OSCs have achieved a power conversion efficiency of 15.21% (16.55%

Abstract Considering their superior charge-transfer characteristics, easy tenability of energy levels, and low production cost, organic semiconductors are ideal for photoelectrochemical (PEC) hydrogen production. However, organic-semiconductor-based photoelectrodes have not been extensively explored for PEC water-splitting because of their low stability in water. Herein, we report high-performance and stable organic-semiconductors photoanodes consisting of p -type polymers and n -type non-fuller

Abstract As a characteristic feature of conventional conjugated polymers, it has been generally agreed that conjugated polymers exhibit either high hole transport property (p‐type) or high electron transport property (n‐type). Although ambipolar properties have been demonstrated from specially designed conjugated polymers, only a few examples have exhibited ambipolar transport properties under limited conditions. Furthermore, there is, as yet, no example with ‘equivalent’ hole and electron trans

Abstract A new n‐type organic semiconductor (n‐OS) acceptor IDTPC with n ‐hexyl side chains is developed. Compared to side chains with 4‐hexylphenyl counterparts (IDTCN), such a design endows the acceptor of IDTPC with higher electron mobility, more ordered face‐on molecular packing, and lower band gap. Therefore, the IDTPC‐based polymer solar cells (PSCs) with a newly developed wide bandgap polymer PTQ10 as donor exhibit the maximum power conversion efficiency (PCE) of 12.2%, a near 65% improve

Compared with conventional organic solar cells (OSCs) based on single donor-acceptor pairs, terpolymer- and ternary-based OSCs featuring multiple donor-acceptor pairs are promising strategies for enhancing the performance while maintaining an easy and simple synthetic process. Using multiple donor-acceptor pairs in the active layer, the key photovoltaic parameters (i.e., short-circuit current density, open-circuit voltage, and fill factor) governing the OSC characteristics can be simultaneously

In an attempt to further improve the performance of the PCDTBT-based polymer solar cells (PSCs), we have synthesized a selenophene analogue of PCDTBT, namely, PCDSeBT, in which diselenienylbenzothiadiazole (DSeBT) monomer alternately flanks with a 2,7-carbazole unit. The intrinsic properties of PCDSeBT are not only characterized by UV–vis absorption, cyclic voltammetry (CV), and organic field-effect transistors (OFETs) but also the surface morphology, mobilities of space charge-limited current (