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Current Research

Perovskite Solar Cells

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Interface Modification

 

Interface modification is an effective strategy to improve the performance of perovskite solar cells. In RENEL, we utilize some new molecules with desired dipoles and wettability toward high efficiency and stable devices

Crystal Passivation for Low Tempertaure PSCs

 

In RENEL, we developed an high-efficiency solar cells with improved long-term stability and negligible hysteresis through the effective passivation of shallow and deep traps in organic-inorganic hybrid perovskite (OIHP) crystals and at the ETL/OIHP interface.

With these strategy, we recorded 22.3% power  conversion efficiency for low temperature processable device.

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Flexible and Large Module 

 

Combining fine-crystal availability, passivation technology, and transport materials quality, we also studied further to develop highly efficient solar device in both of rigid and flexible substrates, also in small and large area.

 

In RENEL, we recorded 19.6% power conversion efficiency in flexible substrate!

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Colorful Devices

 

While research on building-integrated photovoltaics  has mainly focused on power-generating window applications, the utilization of other underutilized surface areas in buildings, including exteriors, facades, and rooftops, has still not been fully explored. The most important requirements for BIPVs are color, power conversion efficiency (PCE), and long-term stability.

 

In RENEL, we achieved colorful (RGB) perovskite solar cells with smallPCE loss (<10%) and enhanced photostability

Organic Thermoelectrics

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Organic Thermoelectrics

Development in wearable thermoelectric (TE) devices, which can achieve self-powering using waste body heat, has received significant attention. To develop high-performance wearable TE devices, the TE materials with desired mechanical properties (i.e., intrinsic flexibility, stretchability, and self-healability all at once) and sufficiently high TE properties are the prerequisites.

- Synthesis of Stretchable Energy Materials

 

- Thermally-Chargable Supercapacitors

 

- Thermo-Electrochemical Cells

Previous Research

OFET

  • The spray technique that we used in solar cells can be easily extended for the fabrication of other organic electronic devices, one of them is Organic Field-Effect Transistor (OFET). Our group successfully fabricated OFETs and the microcrystal domains of the polymer active layers are effectively manipulated using the post-treatment techniques, which is solvent spray overlayer (SSO). Our SSO is a simple, room temperature, an external treatment method that can capitalize on the advantages of spray methods for the fabrication of OFETs. The device performance that we got was high and comparable to the devices fabricated by other conventional methods.

     

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CNT-Graphene

  • Carbon nanotubes (CNT) and graphene are nano-sized carbon materials possessing various unique properties which can be applied for a range of applications such as electronic devices, energy devices, catalysts, and sensors. The main obstacle for the utilization of these materials is limited to the processability. We develop the chemistry for the solution processable CNTs and Graphene.

    Preparation of Graphene

    We prepare graphene via the chemical synthetic method. Chemical synthetic methods of graphene have potentials for large scale preparation which has industrial feasibility. The decent exfoliation of graphene is confirmed by TEM and AFM which indicate the large portion of single-layer graphene is prepared. In the state of a single layer or few-layer graphene, high surface area, catalytic effect, and the charge transport properties are observed. We were applying the chemically prepared graphene to the electrodes for energy devices and active materials for transistors.

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    Organic and Aqueous soluble SWCNTs

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    Aqueous soluble SWCNT was prepared by hybridizing SWNCT with a conjugated block copolymer (PEDOT-b-PEO). This block copolymer functions as a surfactant to disperse the aggregated SWCNT; the conjugated PEDOT block interacts with the basal plane of SWCNTs while the water-soluble PEO block to offer solubility. The CNT/polymer nano-hybrids has a solubility in various organic and aqueous systems. When the solvents were dried, the nano-hybrids had a morphology where the polymers are wrapped SWCNTs which are well-exfoliated one another. The molecular level interaction was confirmed by the PL emission quenching upon an increase of the SWCNT contents. Since the conjugated PEDOT moieties are known to have good electrical properties, the nano-hybrids displayed advanced properties as the transparent conducting electrodes.

    Water Soluble MWCNTs

    Water-soluble MWCNTs were synthesized by grafting PSSNa on the MWCNTs. The synthetic strategy yielded a polyelectrolyte brushed MWCNTs which exhibits high solubility in water. These materials were used for the cathode of DSSC and the fabrication of transparent conducting electrode.

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     Metal nanoparticles decorated CNTs

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    Metal nanoparticle (NP) decorated CNTs are synthesized via a novel sonochemical method in the ionic liquid media. Uniform dispersion of metal-NPs on the CNTs is achieved, and they exhibited enhanced solubility in organic solvents. Transparent conducting electrodes are successfully fabricated vacuum-assisted filtration method. The electrical conductivity of the metal-NP decorated CNTs was> 2 times higher than that of their pristine CNT counterparts.