An all carbon dye sensitized solar cell: A sustainable and low-cost design for metal free wearable solar cell devices.

Lightweight carbon electrodes are the new candidates for photovoltaic devices due to their temperature resistivity, ease of fabrication, and skin comfortability. Herein, a sustainable and facile strategy has been proposed for metal free all carbon dye sensitized solar cell (C-DSSC), assembled by stacking carbon front electrode (CFE) and carbon counter electrode (CCE). The CFE demonstrated adequate light transmittance (70-50%) while maintaining efficient photon absorption and charge separation mechanism due to dye coated TiO2 nanorods (P25-R). The graphene dip coated carbon counter electrode (Gr@CCE) possesses remarkable electro catalytic activity towards I3-/I- redox couple with low charge transfer resistance (RCT = 0.79 Ω). The sustainable design of C-DSSC attained ~6 ± 0.5% efficiency with high photocurrent density of 18.835 mA. cm-2. The superior performance of C-DSSC is accredited to its improved charge mobility, low internal resistance, and better interfacial electrode contact. The thickness of C-DSSC is ≤3 mm eliminates the need for rigid glass in DSSC.

Fabrication of conductive and printable nano carbon ink for wearable electronic and heating fabrics.

Printable Nano carbon colloidal ink has fascinated great attention due to their exceptional potential for large-scale application for powering wearable electronic devices. Though, it is challenging to incorporate various characteristics together such as mechanical stability, solution printability, conductivity, electrocatalytic activity, and heat generating properties in the flexible fabric based electrode system. In this research the development of printable composites made with woven/nonwoven fabrics printed with multiwall carbon nanotubes for flexible and wearable heating system and cathodes for dye-sensitized solar cells (DSSC), respectively. We report a printable carbon ink of multiwall carbon nanotubes (MWCNT) synthesized by globular protein serum bovine albumin (BSA). BSA is amino-rich dispersant used to disperse MWCNT and generate tubular porous carbon matrix. High loading ratio of BSA increases the dispersing power of MWCNT and increased porosity of CNT matrix. The proposed Organic Nanocarbon ink (Organic NC) serve the pathways for electron transport leading to higher heat dissipation as the well high conductivity and electrocatalytic activity. It was interesting to reveal that different kinds of woven and nonwoven fabrics displayed exceptional thermal properties when DC voltage was applied. The heat generating properties were highly dependent on the type of fabric and conductive ink uptake. Our proposed Organic NC printed fabric system exhibited superior conductivity with 15-20â€¯Ω resistivity and lower charge transfer resistance RCT = 2.69 Ω, demonstrated an 8% power conversion efficiency of DSSC. The proposed research paves the ways for solution printable high performance woven and nonwoven conductive and thermoelectric materials for wearable electronics.

Fabrication of a flexible and conductive lyocell fabric decorated with graphene nanosheets as a stable electrode material.

Textile electrodes are highly desirable for wearable electronics as they offer light-weight, flexibility, cost effectiveness and ease of fabrication. Here, we propose the use of lyocell fabric as a flexible textile electrode because of its inherently super hydrophilic characteristics and increased moisture uptake. A highly concentrated colloidal solution of graphene oxide nanosheets (GONs) was coated on to lyocell fabric and was then reduced in to graphene nanosheets (GNs) using facile chemical reduction method. The proposed textile electrode has a very high surface conductivity with a very low value of surface resistance of only 40Ωsq(-1), importantly without use of any binding or adhesive material in the processing step. Atomic force spectroscopy (AFM) and Transmission electron microscopy (TEM) were conducted to study the topographical properties and sheet exfoliation of prepared GONs. The surface morphology, structural characterization and thermal stability of the fabricated textile electrode were studied by field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), X ray photon spectroscopy (XPS), Raman spectroscopy, Wide angle X ray diffraction spectroscopy (WAXD) and Thermogravimetric analysis (TGA) respectively. These results suggest that the GONs is effectively adhered on to the lyocell fabric and the conversion of GONs in to GNs by chemical reduction has no adverse effect on the crystalline structure of textile substrate. The prepared graphene coated conductive lyocell fabric was found stable in water and electrolyte solution and it maintained nearly same surface electrical conductivity at various bending angles. The electrical resistance results suggest that this lyocell based textile electrode (L-GNs) is a promising candidate for flexible and wearable electronics and energy harvesting devices.

Highly Functional TNTs with Superb Photocatalytic, Optical, and Electronic Performance Achieving Record PV Efficiency of 10.1% for 1D-Based DSSCs.

Different nanostructures of TiO2 play an important role in the photocatalytic and photoelectronic applications. TiO2 nanotubes (TNTs) have received increasing attention for these applications due to their unique physicochemical properties. Focusing on highly functional TNTs (HF-TNTs) for photocatalytic and photoelectronic applications, this study describes the facile hydrothermal synthesis of HF-TNTs by using commercial and cheaper materials for cost-effective manufacturing. To prove the functionality and applicability, these TNTs are used as scattering structure in dye-sensitized solar cells (DSSCs). Photocatalytic, optical, Brunauer-Emmett-Teller (BET), electrochemical impedance spectrum, incident-photon-to-current efficiency, and intensity-modulated photocurrent spectroscopy/intensity-modulated photovoltage spectroscopy characterizations are proving the functionality of HF-TNTs for DSSCs. HF-TNTs show 50% higher photocatalytic degradation rate and also 68% higher dye loading ability than conventional TNTs (C-TNTs). The DSSCs having HF-TNT and its composite-based multifunctional overlayer show effective light absorption, outstanding light scattering, lower interfacial resistance, longer electron lifetime, rapid electron transfer, and improved diffusion length, and consequently, J SC , quantum efficiency, and record photoconversion efficiency of 10.1% using commercial N-719 dye is achieved, for 1D-based DSSCs. These new and highly functional TNTs will be a concrete fundamental background toward the development of more functional applications in fuel cells, dye-sensitized solar cells, Li-ion batteries, photocatalysis process, ion-exchange/adsorption process, and photoelectrochemical devices.