Inorganic cesium lead mixed halide based perovskite solar materials modified with functional silver iodide

Inorganic CsPbIBr2 perovskites have recently attracted enormous attention as a viable alternative material for optoelectronic applications due to their higher efficiency, thermal stability, suitable bandgap, and proper optical absorption. However, the CsPbIBr2 perovskite films fabricated using a one-step deposition technique is usually comprised of small grain size with a large number of grain boundaries and compositional defects. In this work, silver iodide (AgI) will be incorporated as an additive into the CsPbIBr2 perovskite precursor solution to prepare the unique perovskite CsI(PbBr2)1-x(AgI)x. The AgI additive in the precursor solution works as a nucleation promoter which will help the perovskite to grow and merge into a continuous film with reduced defects. With detailed characterizations, we found that incorporating AgI additive resulted in a uniform perovskite film with fewer grain boundaries, increased grain size, crystallinity, optical absorption while decreasing carrier recombination and trap density. Using the AgI in an optimum amount, we fabricated CsPbIBr2 perovskite solar cells (PSCs) with a simple structure and achieved a power conversion efficiency (PCE) of 7.2% with a reduced hysteresis index. This work offers an alternative approach towards preparing high-quality CsPbIBr2 perovskite films for solar cells with higher stability and other optoelectronic applications

Effect of Interface Modification on Mechanoluminescence-Inorganic Perovskite Impact Sensors

It is becoming increasingly important to develop innovative self-powered, low-cost, and flexible sensors with the potential for structural health monitoring (SHM) applications. The mechanoluminescence (ML)-perovskite sensor is a potential candidate that combines the light-emitting principles of mechanoluminescence with the light-absorbing properties of perovskite materials. Continuous in-situ SHM with embedded sensors necessitates long-term stability. A highly stable cesium lead bromide photodetector with a carbon-based electrode and a zinc sulfide (ZnS): copper (Cu) ML layer was described in this article. The addition of a magnesium iodide (MgI2) interfacial modifier layer between the electron transport layer (ETL) and the Perovskite interface improved the sensor’s performance. Devices with the modified structure outperformed devices without the addition of MgI2 in terms of response time and impact-sensing applications

Ti-based MXenes for Energy Storage Applications: Structure, Properties, Processing Parameters and Stability

The novel family of two-dimensional transitional metal carbides, nitrides and carbonitrides (Also known as MXenes) is being considered as the next generation of materials because of their unique properties and vast potentiality as the active material in different field of applications, such as sensors, energy storage devices, energy generators, EMI shields etc. Among them, MXenes have great prospects in electrochemical energy-storage application. MXenes show unique properties due to their low dimensional, layered structure which are convenient for energy storage applications. Theoretically, MXenes have high mechanical strength, competitive gravimetric capacitance, and outstanding catalytic properties. However, the advancement of MXenes towards industrial manufacturing is impaired because of poor mechanical and electrochemical properties of experimentally obtained films, poor stability in oxygen rich environment, and lack of scaled-up production protocols. Hence, to fully utilize the outstanding prospects of this novel material, it is important to understand the structure-property relationship, effect of processing parameters, environmental stability, and scale-up scopes of MXenes. In the perspective, this article reviews the structural, electrochemical, and mechanical properties of MXenes, and strategies to control the properties for application-specific requirements. The relationships between synthesis parameters and the properties of MXenes are discussed. Oxidation stability and the proposed strategies to improve shelf-life are also reviewed

Performance analysis of embedded mechanoluminescence-perovskite self-powered pressure sensor for structural health monitoring

Recent developments in sensing technologies have triggered a lot of research interest in exploring novel self-powered, inexpensive, compact and flexible pressure sensors with the potential for structural health monitoring (SHM) applications. Herein, we assessed the performance of an embedded mechanoluminescent (ML) and perovskite pressure sensor that integrates the physical principles of mechanoluminescence and perovskite materials. For a continuous in-situ SHM, it is crucial to evaluate the capabilities of the sensing device when embedded into a composite structure. An experimental study of how the sensor is affected by the embedment process into a glass fiber-reinforced composite has been conducted. A series of devices with and without ML were embedded within a composite laminate, and the signal responses were collected under different conditions. We also demonstrated a successful encapsulation process in order for the device to withstand the composite manufacturing conditions. The results show that the sensor exhibits distinct signals when subjected to different load conditions and can be used for the in-situ SHM of advanced composite structures

A Review on the Out-of-Autoclave Process for Composite Manufacturing

Composite materials have gained increased usage due to their unique characteristic of a high-stiffness-to-weight ratio. High-performing composite materials are produced in the autoclave by applying elevated pressure and temperature. However, the process is characterized by numerous disadvantages, such as long cycle time, massive investment, costly tooling, and excessive energy consumption. As a result, composite manufacturers seek a cheap alternative to reduce cost and increase productivity. The out-of-autoclave (OoA) process manufactures composites by applying vacuum, pressure, and heat outside of the autoclave. This review discusses the common out-of-autoclave processes for various applications. The theoretical and practical merits and demerits are presented, and areas for future research are discussed

A Review on the Out-of-Autoclave Process for Composite Manufacturing

Composite materials have gained increased usage due to their unique characteristic of a high-stiffness-to-weight ratio. High-performing composite materials are produced in the autoclave by applying elevated pressure and temperature. However, the process is characterized by numerous disadvantages, such as long cycle time, massive investment, costly tooling, and excessive energy consumption. As a result, composite manufacturers seek a cheap alternative to reduce cost and increase productivity. The out-of-autoclave (OoA) process manufactures composites by applying vacuum, pressure, and heat outside of the autoclave. This review discusses the common out-of-autoclave processes for various applications. The theoretical and practical merits and demerits are presented, and areas for future research are discussed

Impact sensing and localization in composites structures with embedded mechanoluminescence-perovskite sensors

Mechanoluminescence (ML)-perovskite sensors have shown potential for real-time impact sensing in composites structure. The sensors can be embedded in the structure for in-situ and real-time structural health monitoring (SHM) applications. Our previous work demonstrated the potential of a flexible ML-perovskite sensor for SHM systems and the possibility of sensor embedment in a fiber-reinforced composite structure. However, the viability of the sensor to predict impact localization remains unexplored. This paper investigates the potential of the sensors for impact localization in composite laminates. Herein, embedded ML-perovskite sensors are placed throughout a composite plate to monitor the host structure. By monitoring and correlating the changes in the electrical current of the sensors, it is possible to predict the impact location in the structure. The experimental results show that the ML-perovskite sensor can accurately detect and locate impact events when embedded in a composite structure. This work reveals the potential of ML-perovskite sensors for damage detection and localization prediction in composite materials

Vanadium MXenes materials for next-generation energy storage devices

Batteries and supercapacitors have emerged as promising candidates for next-generation energy storage technologies. The rapid development of new two-dimensional (2D) electrode materials indicates a new era in energy storage devices. MXenes are a new type of layered 2D transition metal carbides, nitrides, or carbonitrides that have drawn much attention because of their excellent electrical conductivity, electrochemical and hydrophilic properties, large surface area, and attractive topological structure. This review focuses on various synthesis methods to prepare vanadium carbide MXenes with and without etchants like hydrofluoric acid, lithium fluoride, and hydrochloric acid to remove the ‘A’ layers of the MAX phase. The goal is to demonstrate the utilization of a less toxic etching method to achieve MXenes of comparable properties to those prepared by traditional methods. The influence of intercalation on the effect of high interlayer spacing between the MXene layers and the performance of MXenes as supercapacitor and battery electrodes is also addressed in this review. Lastly, the gaps in the current knowledge for vanadium carbide MXenes in synthesis, scalability, and utilization in more energy storage devices were discussed