Highly effective 2D layered carbides counter electrode for iodide redox couple regeneration in dye-sensitized solar cells

Fabrication of a free-standing Ti3C2T x -PTh counter electrode via interfacial polymerization for dye-sensitized solar cells

The current work involves the fabrication of a MXene-Polythiophene (Ti3C2T x -PTh) composite via interfacial polymerization, alongside its deployment as a counter electrode (CE) or photocathode in dye-sensitized solar cells (DSSCs). The structural properties of the synthesized materials were investigated through a comprehensive array of techniques, including X-ray diffraction (XRD), fourier-transform infrared (FT-IR) spectroscopy, high resolution scanning electron microscopy (HRSEM), energy-dispersive X-ray analysis (EDAX), and X-ray photoelectron spectroscopy (XPS). The electrochemical performance, assessed via cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), revealed that the Ti3C2T x -PTh CE exhibits superior electro-catalytic activity, and reduction in charge transfer resistance compared to other individual CEs. These observations are in concordance with the data obtained from Tafel analysis. The incorporation of Ti3C2T x sheets into the composite significantly augmented its catalytic efficacy for triiodide reduction, manifesting in elevated short-circuit photocurrent density and enhanced fill factor metrics. A DSSC utilizing the Ti3C2T x -PTh CE exhibited a power conversion efficiency (PCE) of 5.83%, which stands on par with that of traditional Pt CEs. Thus, the Ti3C2T x -PTh CE material is posited as a viable, cost-efficient alternative to Pt, heralding a new era in the engineering of counter electrodes for the next generation of DSSCs.

Investigation and development of photocathodes using polyaniline Encapsulated Ti3C2Tx MXene nanosheets for dye-sensitized solar cells

In the current study, polyaniline (PANI) modified two-dimensional Ti3C2Tx MXene composites (PANI-Ti3C2Tx) are exploited as photocathodes in dye-sensitized solar cells (DSSCs). The study revealed that incorporating PANI into Ti3C2Tx improved the material's electrochemical properties, owing to the presence of amino groups in PANI that enhanced the material's electrical conductivity and thereby facilitated more rapid ion transport. In addition, PANI enhanced the surface wettability of Ti3C2Tx, resulting in an increase in the number of electroactive sites. The presence of PANI molecules in the interlayer and on the surface of Ti3C2Tx was confirmed through X-ray diffraction (XRD), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX), and X-ray photoelectron spectroscopy (XPS). Subsequently, electrochemical analysis of the PANI-Ti3C2Tx photocathode or counter electrode (CE) revealed a commendable electrocatalytic activity with the iodide/triiodide electrolyte, a favourable charge transfer kinetics, and a charge transfer resistance as low as platinum. Additionally, at AM 1.5G, the performance of the DSSC constructed using the thermally decomposed Pt-CE was 8.3% when subjected to simulated 1 sun light, whereas the efficiency of the DSSC constructed using the as-prepared composite material was 6.9% under corresponding conditions. PANI-Ti3C2Tx as the photocathode (CE) in a DSSC showed a higher power conversion efficiency (PCE) improvement than PANI CE and Ti3C2Tx CE DSSCs, emphasizing its potent catalytic activity and quick mass transport of electron capability. By capitalizing on the conductivity and electrocatalytic property of the two components, the as-fabricated PANI-Ti3C2Tx photocathode significantly increased the overall PCE of DSSCs. Furthermore, the DSSC utilizing the PANI-Ti3C2Tx CE demonstrated exceptional reproducibility and stability. This underscores its consistently high performance and significant resistance to corrosion in the iodide/triiodide redox electrolyte environment. Overall, these findings show that the PANI-Ti3C2Tx composite has the potential to be a competitive alternative to platinum-based CE materials for the development of DSSCs with exceptional performance.

Dye-sensitized solar cells based on highly catalytic CNTs/Ti3C2Tx MXenes composite counter electrode

Establishing stable and efficient Pt-free counter electrodes (CEs) is an important challenge for dye-sensitized solar cells (DSSCs). Ti3C2Tx MXene, with its high catalytic activity and conductivity, has gained attention as a CE in DSSCs. The focus of this paper is on the preparation of Ti3C2Tx decorated carbon nanotubes (CNTs) composite electrode materials (CNTs/Ti3C2Tx), and testing their performance as CEs in DSSCs. Through a series of electrochemical tests, a CNTs/Ti3C2Tx CE exhibits good electrocatalytic activity toward iodine-based electrolytes with low charge transfer resistance, which is close to the performance of a Pt CE. The photoelectric conversion efficiency (PCE) of the CNTs/Ti3C2Tx (1.0 wt%) CE-based DSSCs reaches 5.83%, which is much higher than that of the CNTs CE (3.70%), and approximates that of the Pt CE (6.61%). We attribute the improved performance to the synergistic effect of the excellent conductivity and unique two-dimensional chemical structure of Ti3C2Tx MXene. Moreover, the photostability test of continuous light exposure shows that the CNTs/Ti3C2Tx-1.0 wt% (C/T-1.0 wt%) CE exhibits good stability to the electrolyte. Therefore, CNTs/Ti3C2Tx composites can be used as an efficient Pt-free CE for DSSCs in the future.

MXene-modified electrodes and electrolytes in dye-sensitized solar cells

Dye-sensitized solar cells (DSSCs) have attracted much attention as promising tools in renewable energy conversion technology. This is mainly because of their beneficial qualities, such as their impressive efficiency levels and low-cost fabrication techniques. An overview of MXene-modified electrodes in DSSCs is given in this review article. MXenes are two-dimensional (2D) transition metal carbides or nitrides with remarkable properties such as high conductivity and large surface area. MXenes' properties make them an appealing material for various applications, including energy storage, catalysis, and electronic devices. MXene integration enhances ion transport, dye adsorption, and charge transport in DSSC electrodes. In-depth analysis of the use of 2D Mxene and integration with carbon nanotubes (CNTs), reduced graphene oxide (rGO), 2D MoS2, and hybrids like 2D-2D heterostructures for electrode modification in photovoltaics (PVs), including anodes, photoanodes, composite decorated electrodes, counter electrodes (CEs), and electrolytes, is provided in this review article. The effects on the performance metrics of various deposition techniques are discussed and assessed. The use of MXene-modified electrodes in DSSCs suggests potential for enhancing the performance and efficiency of these solar cells in general. The article examines this strategy's potential advantages and implications, illuminating the fascinating advancements in the area and emphasizing MXenes' potential as a valuable substance for renewable energy applications. We also discuss the difficulties and potential benefits of using MXene-modified electrodes in DSSCs and emphasize the need for additional study to enhance stability, optimize MXene integration techniques, and enhance long-term device performance. The scalability and potential of MXene-based electrode modifications for commercial applications are also covered, addressing issues and prospects for the future, focusing on the necessity of more study. Electrodes modified with MXenes can improve DSSC performance and advance sustainable energy conversion.

A Brief Review of the Role of 2D Mxene Nanosheets toward Solar Cells Efficiency Improvement

This article discusses the application of two-dimensional metal MXenes in solar cells (SCs), which has attracted a lot of interest due to their outstanding transparency, metallic electrical conductivity, and mechanical characteristics. In addition, some application examples of MXenes as an electrode, additive, and electron/hole transport layer in perovskite solar cells are described individually, with essential research issues highlighted. Firstly, it is imperative to comprehend the conversion efficiency of solar cells and the difficulties of effectively incorporating metal MXenes into the building blocks of solar cells to improve stability and operational performance. Based on the analysis of new articles, several ideas have been generated to advance the exploration of the potential of MXene in SCs. In addition, research into other relevant MXene suitable in perovskite solar cells (PSCs) is required to enhance the relevant work. Therefore, we identify new perspectives to achieve solar cell power conversion efficiency with an excellent quality-cost ratio.