Matt Carnie

Swansea University | SWAN · Department of Materials Engineering

Small perturbation techniques have proven to be useful tools for the investigation of perovskite solar cells. A correct interpretation of the spectra given by impedance spectroscopy (IS), intensity-modulated photocurrent spectroscopy (IMPS) and intensity-modulated photovoltage spectroscopy (IMVS) is key for the understanding of device operation. Th...

In this paper, we review and describe how different pho-tovoltaic (PV) materials can be used for designing self-powered interfaces and interactions using indoor ambient light to both power the device and to detect simple shadow-based gestures. We consider seven points when comparing the material technologies: device efficiency, device stability, de...

The toxicity, earth abundance and manufacturing costs of thermoelectric materials are three leading reasons why thermoelectric generators are not used in wide scale applications. This is the first paper to tackle all three of these problems simultaneously. A pseudo-3D printing technique is combined with Cu2-xS based inks to yield bulk samples capab...

Since the discovery of the record figure of merit (ZT) of 2.6 ± 0.3 in tin selenide (SnSe), the material has attracted much attention in the field of thermoelectrics. This paper reports a novel pseudo‐3D printing technique to fabricate bulk SnSe thermoelectric elements, allowing for the fabrication of standard configuration thermoelectric generator...

Transient photovoltage and impedance spectroscopy measurements reveal how degradation affects both the active layer and the interlayer in OPV devices.

Internet of Things (IoT) technology is found in many homes. These systems enable tasks to be done more effectively or efficiently-e.g., securing property, monitoring and adjusting resources, tracking behaviours for well-being, and so on. The system presented here was designed with older adults; the vast majority of home IoT systems marketed to this...

For commercial applications, Perovskite Solar Cells (PSCs) need to be well encapsulated to improve long term stability. The most common method, glass-glass encapsulation, uses edge sealant materials to encapsulate the device between sheets of glass. Glass-Glass encapsulation, while providing provide adequate protection from the ambient environment,...

As the Internet of Things (IoT) expands, the need for energy-efficient, self-powered devices increases. This study examines light power resource availability for photovoltaics (PV) in various environments and its potential in self-powered IoT applications. We analyse light sources, considering spectral distribution, intensity, and temporal variatio...

This paper presents the design and implementation process of a portable IoT source-sink meter system for real-world indoor photovoltaic (PV) module testing. Specifically tailored for indoor environments and low-light conditions, the meter offers a comprehensive and automated solution for monitoring and testing the performance of various PV module t...

Clearcoats provide long-term aesthetics and protection for underlying coating systems, increasing product lifetimes. However, organic clearcoats are predominantly produced using fossil-fuel feedstocks. In search of a sustainable alternative, an experimental investigation was conducted on the development of glass-like clearcoats produced using the s...

There has been much interest in tin selenide (SnSe) in the thermoelectric community since the discovery of the record zT in the material in 2014. Manufacturing techniques used to produce SnSe are largely energy-intensive (e.g., spark plasma sintering); however, recently, in previous work, SnSe has been shown to be produced via a low embodied energy...

Tin selenide (SnSe) has attracted much attention in the field of thermoelectrics since the discovery of the record figure of merit (zT) of 2.6 ± 0.3. While there have been many publications on p-type SnSe, to manufacture efficient SnSe thermoelectric generators, ann-type is also required. Publications on n-type SnSe, however, are limited. This pape...

Metastability is a characteristic feature of perovskite solar cell (PSC) devices that affects power rating measurements and general electrical behaviour. In this work the metastability of different types of PSC devices is investigated through current-voltage (I-V) testing and voltage dependent photoluminescence (PL-V) imaging. We show that advanced...

Implantable biomedical electronics, such as pacemakers, drug pumps, cochlear implants, cardioverter-defibrillators, and neurological stimulators, help humans to overcome various diseases. Currently, the power supply for these devices relies on small-size batteries, and replacement of the battery is required after running for a period of time. Recha...

Perovskite photovoltaics have shown great promise in device efficiency but also the promise of scalability through solution-processed manufacture. Efforts to scale perovskites have been taken through printable mesoporous scaffolds and slot die coating of flexible substrates roll to roll. However, to date there has been no demonstration of entirely...

We reported two tetraphenylpyrrolo[3,2‐b]pyrroles in which the central core is functionalized by electron-rich functions: methoxy and di(4-methoxyphenyl)aminyl. The targeted compounds have good solubility in common organic solvents, high thermal stability and glass forming capacity. The optical and electrochemical properties of these compounds sugg...

Fully printable carbon-based perovskite solar cells (C-PSCs) represent some of the most promising perovskite solar cell (PSC) architectures. Highly scalable, stable, and low in cost—these devices consist of a TiO2 compact layer (C-TiO2) and three sequentially screen-printed mesoporous layers of TiO2, ZrO2, and carbon, through which perovskite is in...

OPEN ACCESS Solar cells offer a route to exceed the Shockley–Queisser limit for single-junction devices. In a few short years, silicon-perovskite tandems have significantly passed the efficiency of the best silicon single-junction cells. For scalable solution processing of silicon-perovskite tandem devices, with the avoidance of vacuum processing...

Impedance Spectroscopy (IS) has proven to be a powerful tool for the extraction of significant electronic parameters in a wide variety of electrochemical systems, such as solar cells or electrochemical cells. However, this has not been the case with perovskite solar cells, which have the particular ionic-electronic combined transport that complicat...

Parasitic optical losses from interlayers in silicon-perovskite tandems reduce charge generation and impact on device performance. This paper explores the trade off in optoelectronic properties of room temperature deposited indium zinc oxide (IZO) films as a transparent conductive oxide (TCO) for NIP silicon perovskite tandem cells. The optical per...

Organic semiconductor‐based photovoltaic (OPV) devices have many properties that make them attractive for indoor applications, such as tailorable light absorption, low embodied energy manufacturing and cost, structural conformality, and low material toxicity. Compared to their use as organic solar cells (OSCs) for standard outdoor solar harvesting,...

The looming impact of climate change and the diminishing supply of fossil fuels both highlight the need for a transition to more sustainable energy sources. Whilst solar and wind can produce much of the energy needed, to meet all our energy demands there is a need for a diverse sustainable energy generation mix. Thermoelectrics can play a vital rol...

Recent developments of solution‐processed bulk‐heterojunction organic photovoltaic (OPV) cells have demonstrated power conversion efficiencies (PCEs) as high as 18% for single‐junction devices. Such a high PCE in addition to its desirable lightweight property and high mechanical flexibility can realize high specific power and small stowed volume, w...

The number of interconnected devices, often referred to as the Internet of Things (IoT), is increasing at a considerable rate. It is inevitable therefore that so too will the energy demand. IoT describes a range of technologies such as sensors, software, smart meters, wearable devices, and communication beacons for the purpose of connecting and exc...

Thermoelectric materials can convert waste heat to electricity without moving parts. Extensive research into improving the efficiency of inorganic thermoelectric materials has allowed some materials such as bismuth tellurides to be commercialized. These materials, however, contain materials in low abundance on earth such as tellurium therefore thei...

Mesoscopic carbon-based perovskite solar cells (CPSCs) are frequently described as a potential frontrunner for PSC commercialization. Previous work has introduced γ-valerolactone (GVL) as a sustainable, non-toxic, green alternative to GBL for CPSC perovskite precursors. In this work, methanol (MeOH) solvent additives are applied to enhance the perf...

Application of different bandgap perovskite materials and alternative hole transport layers to monolithic NIP silicon perovskite tandem solar cells and exploration of the effect on current matching between the two sub-cells.

The complete interpretation of small perturbation frequency‐domain measurements on perovskite solar cells has proven to be challenging. This is particularly true in the case of intensity modulated photocurrent/photovoltage (IMPS/IMVS) measurements, in which the high frequency response is obscured by instrument limitations. Herein, we demonstrate a...

As practical interest in the flexible or wearable thermoelectric generators (TEGs) has increased, the demand for the high-performance TEGs based on ecofriendly, mechanically resilient, and economically viable TEGs as alternatives to the brittle inorganic materials is growing. Organic or hybrid thermoelectric (TE) materials have been employed in fle...

Graphene exhibits both high electrical conductivity and large elastic modulus, which makes it an ideal material candidate for many electronic devices. At present not much work has been conducted on using graphene to construct thermoelectric devices, particularly due to its high thermal conductivity and lack of bulk fabrication. Films of graphene-ba...

Properties of the electron transport layer (ETL) are known to influence the performance of lead halide perovskite solar cells (PSCs). But so far very little emphasis has been given on the increased impact of this layer at low light. In this work we compare the effect of thickness and coverage of a TiO2 compact layer on the performance and hysteresi...

Tin selenide (SnSe) has attracted much attention in the thermoelectric community since the discovery of the record ZT of 2.6 in single crystal tin selenide in 2014. There have been many reports since of the thermoelectric characterization of SnSe synthesized or manufactured by several methods, but so far none of these have concerned the electrodepo...

The continued proliferation of computing devices comes with an ever-increasing energy requirement, both during production and use. As awareness of the global climate emergency increases, self-powered and sustainable (Self-Sustainable) interactive devices are likely to play a valuable role. In this workshop we bring together researchers and practiti...

With the rapid rise in connectivity in the home, office, and public spaces through the internet of things (IoT), there is a need for an increase in off grid and self-sustainable power solutions for the growing energy requirements of interconnected devices. Here we present an off-grid option for powering a simple IoT device in the home/office. We de...

A two-step approach of improving the thermoelectric properties of Poly(3,4-ethylenedioxythiophene)poly(4-styrenesulfonate) (PEDOT:PSS) via the addition of the ionic liquid, 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM:TFSI) and subsequent reduction with NaBH4 is presented. The addition of 2.5 v/v% of EMIM:TFSI to PEDOT:PSS in...

Carbon based Perovskite Solar cells (C–PSCs) have emerged as the most promising candidates for commercialisation in the field of perovskite photovoltaics, as they are highly stable, low cost and make use of easily scaled manufacturing techniques. However, the limited conductivity of the carbon electrode inhibits performance and represents a signifi...

The interactive, digital future with its seductive vision of Internet-of-Things connected sensors, actuators and displays comes at a high cost in terms of both energy demands and the clutter it brings to the physical world. But what if such devices were made of materials that enabled them to self-power their interactive features? And, what if those...

Метил–аммониевые свинцово–галоидные перовскиты широко признаны в качестве многообещающих материалов для фотоэлектрических приложений. Популярность этих материалов основана на высокой эффективности готовых фотопреобразователей, сопоставимой с эффективностью промышленных кремниевых солнечных элементов, а также на возможности значительного уменьшения...

Perovskite solar cells with high power-per-weight have great potential to be used for aerospace applications such as satellites or high-altitude pseudo-satellites. These latter are unmanned aircrafts exclusively powered by solar energy, typically flying in the stratosphere where conditions of pressure, temperature and illumination are critically di...

Due to their high specific power and potential to save both weight and stow volume, perovskite solar cells have gained increasing interest to be used for space applications. However, before they can be deployed into space, their resistance to ionizing radiations such as high‐energy protons must be demonstrated. In this report, we investigate the ef...

A range of slow dynamic processes occurring in perovskite solar cells have been linked to ionic migration, including J-V hysteresis and long photovoltage rise and decay times. This work demonstrates the remarkably slow response time of triple mesoporous carbon-based cells, containing the additive 5-aminovaleric acid iodide (AVA). The photovoltage r...

X-ray Photoelectron spectroscopy (XPS) spectra of methyl ammonium lead halide perovskite films typically show the presence of lead as Pb(II), but Pb(0) is also often observed, potentially influencing the interpretation of the device physics. In this article the reproducible evolution of Pb(0) peaks which are likely artefacts generated under typical...

A commercially available glass substrate which incorporates both a fluorine‐doped tin oxide and compact TiO2 layer deposited through chemical vapor deposition that is commonly used in “solar control products,” is presented. The substrate, known commercially as Pilkington Eclipse Advantage, is designed for use as an infrared radiation control produc...

The fully printed, hole-transporter-free carbon perovskite solar cell structure incorporating a triple mesoscopic layer has emerged as a possible frontrunner for early industrialisation. It is an attractive structure because it can be fabricated by the simple sequential screen printing and sintering of titania, zirconia, and carbon. The device is f...

Indoor photovoltaics is one of the best sustainable and reliable energy source for low power consumption electronics such as the rapidly growing Internet of Things. Perovskite photovoltaic (PPV) cells with three benchmark device architectures – mesoporous PPV (mPPV) and inverted PPV (iPPV) with alternative hole transporting layers (HTLs), and carbo...

Colloidal TiO2 films have been prepared using a binder-free aqueous paste with Degussa P25 and hexafluorotitanic acid (H2TiF6), which was optimised for different substrates. Dye-sensitized solar cells (DSSC) fabricated using this paste were sintered at (ca. 393 K) and efficiencies (η) of 3.0, 4.2 and 6.1% were measured for devices using titanium fo...

A study of a local industrial symbiosis involving the recovery of platinum from waste thermocouples which is then used for the preparation of catalytic electrodes suitable for dye sensitized solar cell production is reported. The small quantity of platinum in the filaments of used thermocouples, thousands of which are discarded each year by metal f...

CaCO3-templating is a strategy for synthesizing porous carbon (PC) materials that has been widely used for decades. In this work, a modified template-removal process, soaking the pyrolysis product by hydrochloric acid solution, was proposed to optimize the graphitization degree, morphology, specific area, and pore size distribution of the products....

Tin selenide (SnSe) has attracted much attention in the field of thermoelectrics since the discovery of the record figure of merit (ZT) of 2.6 ± 0.3 along the b‐axis of the material. The record ZT is attributed to an ultralow thermal conductivity that arises from anharmonicity in bonding. While it is known that nanostructuring offers the prospect o...

The optimisation of the interface between back contact and absorber is one of the main challenges to improve the electrical behaviour and further enhance the efficiencies of Cu2ZnSn(S,Se)4 (CZTS(e)) solar cell devices. In this work, Mo/SixNy thin films with various film thicknesses were introduced as an interfacial layer to explore its influence on...

The ideality factor determined by measuring the open circuit voltage (VOC) as function of light intensity is often used as a means to identify the dominant recombination mechanism in solar cells. However, applying this Suns-VOC technique to perovskite cells is problematic since the VOC evolves with time in a way which depends on the previously appl...