Studi Komputasi Modifikasi Struktur Zat Warna Tipe D-Π-A Berbasis Indolin untuk Meningkatkan Kinerja Dye-Sensitized Solar Cells (Dsscs)

Studi Komputasi Modifikasi Struktur Zat Warna Tipe D-Π-A Berbasis Indolin untuk Meningkatkan Kinerja Dye Sensitized Solar Cells (DSSCs) Oleh: Putri Arwanda (1610411032) Imelda, M.Si*, Prof. Dr. Hermansyah Aziz* *Pembimbing Pada Dye Sensitized Solar Cells (DSSCs) terdapat sensitizer yang berperan penting dalam efisiensi penyerapan cahaya. Sensitizer yang biasa digunakan adalah zat warna organik dan anorganik. Zat warna organik tersedia melimpah di alam, biaya produksi relatif murah, ramah lingkungan, namun efisiensi serapan cahaya masih rendah. Oleh karena itu, untuk meningkatkan efisiensi serapan cahaya maka diperlukan modifikasi struktur zat warna organik. Zat warna modifikasi yang berkembang adalah zat warna organik tipe D-π-A. yang terdiri dari rantai donor elektron, rantai π-konjugasi dan akseptor elektron. Dalam penelitian ini dianalisa zat warna berbasis Indolin yang didesain sebagai rantai donor, piridin, kuinolin, pirimidin, purin, isokuinolin sebagai rantai π-konjugasi, asam asetat, asam benzoat, asam kloroasetat, asam sianoakrilik, asam format sebagai rantai akseptor. Pada zat warna terbaik kemudian ditambahkan gugus pendorong elektron C2H5, CH3, NH2 dan gugus penarik elektron Cl, NO2, OH. Molekul digambarkan menggunakan jendela Gauss View 6.0 dan dioptimasi menggunakan paket Gaussian 16W dengan metode DFT/TDDFT dan basis set B3LYP/6-31G. Berdasarkan hasil perhitungan nilai bandgap, λ, energi eksitasi, LHE, Voc maka diprediksi zat warna 6 dengan rantai donor indolin, rantai π-konjugasi purin dan rantai akseptor asam asetat menghasilkan efesiensi serapan cahaya yang lebih besar sehingga menghasilkan efesiensi daya DSSCs yang lebih besar juga. Adanya gugus pendorong NH2 pada zat warna 6 menghasilkan bandgap sebesar 0,7543 eV lebih kecil dibandingkan gugus pendorong elektron lainnya. Sedangkan adanya gugus penarik NO2 pada zat warna 6 menghasilkan bandgap lebih kecil sebesar 0,1836 eV dibandingkan gugus penarik elektron lainnya. Dapat disimpulkan bahwa penambahan gugus pendorong maupun penarik elektron mampu meningkatkan efesiensi daya DSSCs Kata kunci: Indolin, DFT/TDDFT, Sensitizer, zat warna, DSSCs ABSTRACT Computational Study on The Modification of Indolin-Based Dye Sensitizer D-π-A Type for Dye Sensitized Solar Cells (DSSCs) By: Putri Arwanda (1610411032) Imelda, M.Si*, Prof. Dr. Hermansyah Aziz* *Supervisor Dye Sensitized Solar Cells (DSSCs) have sensitizers that play an important role in light absorption. The sensitizers that are commonly used are organic and inorganic dyes. Organic dyes are abundant in nature, relatively cheap production costs, environmentally friendly, but the efficiency of light absorption is still low. Therefore, to increase the efficiency of light absorption, it is necessary to modify the structure of the organic dyes. The modified dye that develops is an organic substance of type D-π-A. consisting of a donor electron chain, a π-conjugate chain and an electron acceptor. This study analyzed indoline based-dyes which are designed as donor chains and pyridine, quinoline, pyrimidine, purine, isoquinoline as a π-conjugate chains as well as acetic acid, benzoic acid, chloroacetic acid, cyanoacrylic acid, formic acid as acceptor chains. The best dye is added to the electron donating group (EDG) i.e C2H5, CH3, NH2 and electron withdrawing groups (EWG) i.e Cl, NO2, OH. Molecules were described using the Gauss View 6.0 and optimized using the Gaussian 16W package with the DFT / TDDFT method and the B3LYP / 6-31G basis set. Based on the calculation of the bandgap value, λ, excitation energy, LHE, Voc, it is predicted that dye 6 with the indoline donor chain, the πconjugate purine chain and the acetic acid acceptor chain produce greater light absorption efficiency resulting in greater efficiency of DSSCs power as well. The presence of the NH2 in dye 6 results a bandgap of 0.7543 eV smaller than the other electron donating groups. Whereas the presence of the NO2 in dye 6 results bandgap of 0.1836 eV smaller compared to other electron-withdrawing groups. It can be excluded that the addition of both the EDG and EWG can improve the power efficiency of DSSCs. Keywords: Indolin, DFT / TDDFT, Sensitizer, dyes, DSSC

ZnO Nanowires for Dye Sensitized Solar Cells

This chapter provides a broad review of the latest research activities focused on the synthesis and application of ZnO nanowires (NWs) for dye‐sensitized solar cells (DSCs) and composed of three main sections. The first section briefly introduces DSC‐working principles and ZnO NW application advantages and stability issues. The next section reviews ZnO NW synthesis methods, demonstrating approaches for controlled synthesis of different ZnO NW morphology and discussing how this effects the overall efficiency of the DSC. In the last section, the methods for ZnO NW interface modification with various materials are discussed, which include ZnO core‐shell structures with semiconductive or protective layers, ZnO NW hybrid structures with other materials, such as nanoparticles, quantum dots and carbon nanomaterials and their benefit for charge and light transport in DSCs. The review is concluded with some perspectives and outlook on the future developments in the ZnO nanowire application for DSCs

Synthesis of titanate nanofibers co-sensitized with ZnS and Bi2S3 nanocrystallites and their application on pollutants removal

The synthesis of nanocomposite materials combining titanate nanofibers (TNF) with nanocrystalline ZnS and Bi2S3 semiconductors is described in this work. The TNF were produced via hydrothermal synthesis and sensitized with the semiconductor nanoparticles, through a single-source precursor decomposition method. ZnS and Bi2S3 nanoparticles were successfully grown onto the TNF's surface and Bi2S3-ZnS/TNF nanocomposite materials with different layouts were obtained using either a layer-by-layer or a co-sensitization approach. The samples' photocatalytic performance was first evaluated through the production of the hydroxyl radical using terephthalic acid as probe molecule. All the tested samples show photocatalytic ability for the production of this oxidizing species. Afterwards, the samples were investigated for the removal of methylene blue. The nanocomposite materials with best adsorption ability for the organic dye were the ZnS/TNF and Bi2S3ZnS/TNF. The removal of the methylene blue was systematically studied, and the most promising results were obtained considering a sequential combination of an adsorption-photocatalytic degradation process using the Bi2S3ZnS/TNF powder as a highly adsorbent and photocatalyst material.Comment: 26 pages, 10 figure

Solar Cells

The second book of the four-volume edition of "Solar cells" is devoted to dye-sensitized solar cells (DSSCs), which are considered to be extremely promising because they are made of low-cost materials with simple inexpensive manufacturing procedures and can be engineered into flexible sheets. DSSCs are emerged as a truly new class of energy conversion devices, which are representatives of the third generation solar technology. Mechanism of conversion of solar energy into electricity in these devices is quite peculiar. The achieved energy conversion efficiency in DSSCs is low, however, it has improved quickly in the last years. It is believed that DSSCs are still at the start of their development stage and will take a worthy place in the large-scale production for the future

Theoretical Study on Thin Film Dye Sensitized Photovoltaic Solar Cells

This thesis presents two models of a dye-sensitized solar cell (DSC): diffusion model and electrical model. The main purpose is to investigate interfacial charge transfer and charge transport within the semiconductor/electrolyte layer under illuminated conditions. These two interrelated models confirm that diffusion is the major driving force for electron and ion transport, while the drift of electrons is negligible. The diffusion model was utilized to simulate the temperature influence on the overall efficiency of DSC with a consideration of the voltage loss at titanium dioxide (TiO2)/ transparent conductive oxide (TCO) interface. It reveals that low temperature conditions have serious detrimental effects on the DSCs' performance. Further the electrical model was used to analyze the effect of diffusion/drift, dye loading, and electrode thickness on DSC performance. The predicted optimal electrode thickness ranges between 10-15 μm which is consistent with the thickness (10 μm) used in experimental studies published in the literature

Nanostructured semiconductor materials for dye-sensitized solar cells

Since O'Regan and Grätzel's first report in 1991, dye-sensitized solar cells (DSSCs) appeared immediately as a promising low-cost photovoltaic technology. In fact, though being far less efficient than conventional silicon-based photovoltaics (being the maximum, lab scale prototype reported efficiency around 13%), the simple design of the device and the absence of the strict and expensive manufacturing processes needed for conventional photovoltaics make them attractive in small-power applications especially in low-light conditions, where they outperform their silicon counterparts. Nanomaterials are at the very heart of DSSC, as the success of its design is due to the use of nanostructures at both the anode and the cathode. In this review, we present the state of the art for both n-type and p-type semiconductors used in the photoelectrodes of DSSCs, showing the evolution of the materials during the 25 years of history of this kind of devices. In the case of p-type semiconductors, also some other energy conversion applications are touched upon. © 2017 Carmen Cavallo et al

GUMBOS and NanoGUMBOS: Applications as Photosensitizers in Dye-sensitized Solar Cells

Renewable energy is a major concern due to increased world energy consumption. In particular, solar energy is a type of renewable energy source that uses devices known as solar cells to convert sunlight to electricity. Specifically, devices referred to as dye-sensitized solar cells (DSSCs) employ dyes to absorb solar energy. Dyes derived from ruthenium complexes have been typically used in DSSCs. Unfortunately, several disadvantages are associated with current ruthenium complex photosensitizers, which can be attributed to limited supply and expense of metals, as well as reduced absorption in the near-infrared region of the electromagnetic spectrum. Accordingly, this dissertation is a discussion of novel dyes referred to as group of uniform materials based on organic salts (GUMBOS) for application as photosensitizers in DSSCs. These GUMBOS are solid phase organic salts composed of bulky ions that have melting points from 25°C to 250°C. Importantly, GUMBOS can be tuned for multiple functions based on selected ions resulting in interesting physiochemical properties. In addition, nanomaterials derived from GUMBOS (nanoGUMBOS) can also result in significant properties. The first part of this dissertation involves the synthesis and characterization of nanoGUMBOS from cyanine dyes. These nanomaterials are prepared via a facile self-assembly approach, and spectral and electrochemical properties are investigated. In one study, controlled properties of cyanine-based nanoGUMBOS are found to be dependent on the counterion associated with the cationic dye. In another study, GUMBOS derived from cyanine dyes with increasing methine chain lengths are synthesized. In addition, binary nanomaterials consisting of two different cyanine methine chain length GUMBOS are prepared. The effect of Förster resonance energy transfer between these latter nanomaterials enhances fluorescence into the near-infrared region of the electromagnetic spectrum. The individual and binary nanoGUMBOS offer possible use as sensitizers that extend into the near-infrared region of the electromagnetic spectrum. The second part of this dissertation entails the incorporation of cyanine-based GUMBOS and nanoGUMBOS into DSSCs. In this study, various preparation methods are used for formation of titanium dioxide semiconductor electrodes. Solar cells comprised of these electrodes and cyanine-based GUMBOS are fabricated, and the performances of these DSSCs are investigated