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A study was conducted to show that thiol-terminated single-stranded deoxyribonucleic acids (ssDNA) can be immobilized onto pulsed plasma deposited poly(allylmercaptan) surfaces through disulfide bridge chemistry and are found to readily undergo nucleic acid hybridization. The approach, unlike other methods for oligonucleotide attachment to solid surfaces, is independent of substrate material or geometry and amenable to highly efficient rewriting.

Cu 2 ZnSnS 4 (CZTS) is a narrow band gap, non-toxic, and environmentally friendly semiconductor with important properties for photovoltaic and electro-/photo-catalytic applications. In this study, we report on the synthesis of CZTS nanoparticles (NPs) by a simple and promising hot-injection technique using environmentally friendly, earth-abundant, and low-cost copper and zinc acetates in combination with tin chloride and elemental sulphur. Oleylamine was used as solvent and capping agent. The influence of injection temperatures on the crystalline size, morphology and crystal structure were studied. The formation of detrimental phases has been investigated, as well as their removal by using an HCl treatment during the purification step of the CZTS NPs synthesis process. Raman spectroscopy, X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) analyses were used to investigate the formation mechanism of the CZTS NPs. The experimental results showed that the injection temperature influences the NPs growth. Thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FTIR-ATR) analyses were used to confirm the removal of both organic traces and detrimental phases. It was found that HCl treatment plays a key role in the successful removal of impurities without altering the final crystalline composition profile or NPs surface., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The heterostructure WO 3 /BiVO 4 -based photoanodes have garnered significant interest for photoelectrochemical (PEC) solar-driven water splitting to produce hydrogen. However, challenges such as inadequate charge separation and photocorrosion significantly hinder their performance, limiting overall solar-to-hydrogen conversion efficiency. The incorporation of cocatalysts has shown promise in improving charge separation at the photoanode, yet mitigating photocorrosion remains a formidable challenge. Amorphous metal oxide-based passivation layers offer a potential solution to safeguard semiconductor catalysts. We examine the structural, surface morphological, and optical properties of two-step-integrated sputter and spray-coated TiO 2 thin films and their integration onto WO 3 /BiVO 4 , both with and without NiOOH cocatalyst deposition. The J - V experiments reveal that the NiOOH cocatalyst enhances the photocurrent density of the WO 3 /BiVO 4 photoanode in water splitting reactions from 2.81 to 3.87 mA/cm 2 . However, during prolonged operation, the photocurrent density degrades by 52%. In contrast, integrated sputter and spray-coated TiO 2 passivation layer-coated WO 3 /BiVO 4 /NiOOH samples demonstrate a ∼88% enhancement in photocurrent density (5.3 mA/cm 2 ) with minimal degradation, emphasizing the importance of a strategic coating protocol to sustain photocurrent generation. We further explore the feasibility of using natural mine wastewater as an electrolyte feedstock in PEC generation. Two-compartment PEC cells, utilizing both fresh water and metal mine wastewater feedstocks exhibit 66.6 and 74.2 μmol/h cm 2 hydrogen generation, respectively. Intriguingly, the recovery of zinc (Zn 2+ ) heavy metals on the cathode surface in the mine wastewater electrolyte is confirmed through surface morphology and elemental analysis. This work underscores the significance of passivation layer and cocatalyst coating methodologies in a sequential order to enhance charge separation and protect the photoanode from photocorrosion, contributing to sustainable hydrogen generation. Additionally, it suggests the potential of utilizing wastewater in electrolyzers as an alternative to freshwater resources., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

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 printing technique, resulting in 3D samples with high zT values (up to 1.7). Due to the additive manufacturing technique, the manufacturing time required was substantial. In this work, 3D samples were printed using the inorganic binder sodium metasilicate and reusable molds. This facilitated a single-step printing process that substantially reduced the manufacturing time. The printed samples were thermally stable through multiple thermal cycles, and a peak zT of 0.751 at 823 K was observed with the optimum binder concentration. A proof-of-concept thermoelectric generator produced the highest power output of any reported printed Se-based TEG to date.

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 (R2R). However, to date there has been no demonstration of entirely R2R-coated devices due to the lack of a compatible solution-processable back electrode; instead, high-value evaporated metal contacts are employed as a post process. Here, in this study, the combination of a low-temperature device structure and R2R-compatible solution formulations is employed to make a fully R2R printable device architecture overcoming interlayer incompatibilities and recombination losses. Therefore, the n-i-p device structure of SnO 2 /perovskite/poly(3,4-ethylenedioxythiophene)/carbon is employed to form an ohmic contact between a p-type semiconductor and printable carbon electrode. In particular, the results show that the small-scale device efficiencies of 13-14% are achieved, matching the device performance of evaporated gold electrodes. Also, this entirely R2R-coated perovskite prototype represents a game changer, reaching over 10% (10.8) stabilized power conversion efficiency with unencapsulated long-term stability retaining 84% of its original efficiency over 1000 h under 70% RH and 25 °C., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Tin selenide (SnSe) has attracted much attention in the thermoelectric community since the discovery of the record figure of merit (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 electrodeposition of SnSe. In this work, stoichiometric SnSe was successfully electrodeposited at -0.50 V vs SCE as shown by EDX, XPS, UPS, and XRD. The full ZT of the electrodeposits were then measured. This was done by both a delamination technique to measure the Seebeck coefficient and electrical conductivity which showed a peak power factor of 4.2 and 5.8 μW m -1 K -2 for the as deposited and heat-treated films, respectively. A novel modified transient 3ω method was used to measure the thermal conductivity of the deposited films on the deposition substrate. This revealed the thermal conductivity to be similar to the ultralow thermal conductivity of single crystal SnSe, with a value of 0.34 W m -1 K -1 being observed at 313 K.

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 NaBH 4 is presented. The addition of 2.5 v/v% of EMIM:TFSI to PEDOT:PSS increases the electrical conductivity from 3 S·cm -1 to 1439 S·cm -1 at 40 °C. An additional post treatment using the reducing agent, NaBH 4 , increases the Seebeck coefficient of the film from 11 µV·K -1 to 30 µV·K -1 at 40 °C. The combined treatment gives an overall improvement in power factor increase from 0.04 µW·m -1 ·K -2 to 33 µW·m -1 ·K -2 below 140 °C. Raman and XPS measurements show that the increase in PEDOT:PSS conductivity is due to PSS separation from PEDOT and a conformational change of the PEDOT chains from the benzoid to quinoid molecular orientation. The improved Seebeck coefficient is due to a reduction of charge carriers which is evidenced from the UV-VIS depicting the emergence of polarons.

The demonstration of photovoltaic devices with high power conversion efficiencies using low cost perovskite materials hints at the possibility of dramatically lowering the cost of solar energy. Key to further exploiting the potential of these materials is developing rapid processing techniques that can be used to deliver lower cost high throughput manufacture. This work details the development of low viscosity rapid drying perovskite formulations designed to give high quality solar films when slot-die coated on flexible roll-to-roll compatible substrates. A single step slot-die compatible perovskite ink based on an acetonitrile/methylamine solvent system utilizing a chloride additive is developed, resulting in large area perovskite films from slot-die coating under ambient conditions. The drying conditions for the perovskite film are optimized and fast (<10 min), low temperature (<120 °C) drying of slot-die coated films on flexible substrates are demonstrated and result in high performance devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Dye-sensitized solar cells (DSCs) have been the subject of wide-ranging studies for many years because of their potential for large-scale manufacturing using roll-to-roll processing allied to their use of earth abundant raw materials. Two main challenges exist for DSC devices to achieve this goal; uplifting device efficiency from the 12 to 14% currently achieved for laboratory-scale 'hero' cells and replacement of the widely-used liquid electrolytes which can limit device lifetimes. To increase device efficiency requires optimized dye injection and regeneration, most likely from multiple dyes while replacement of liquid electrolytes requires solid charge transporters (most likely hole transport materials - HTMs). While theoretical and experimental work have both been widely applied to different aspects of DSC research, these approaches are most effective when working in tandem. In this context, this perspective paper considers the key parameters which influence electron transfer processes in DSC devices using one or more dye molecules and how modelling and experimental approaches can work together to optimize electron injection and dye regeneration.

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 of enhanced thermoelectric performance, there have been minimal studies in the literature to date of the thermoelectric performance of thin films of SnSe. In this work, preferentially orientated porous networks of thin film SnSe nanosheets are fabricated using a simple thermal evaporation method, which exhibits an unprecedentedly low thermal conductivity of 0.08 W m -1 K -1 between 375 and 450 K. In addition, the first known example of a working SnSe thermoelectric generator is presented and characterized., (© 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A simple two-step plasmachemical methodology is outlined for the fabrication of microcondensor surfaces. This comprises the creation of a superhydrophobic background followed by pulsed plasma deposition of a hydrophilic polymer array. Microcondensation efficiency has been explored in terms of the chemical nature of the hydrophilic pixels and their dimensions. These results are compared to the hydrophilic-hydrophobic pattern present on the Stenocara beetle's back, which is used by the insect to collect water in the desert. Potential applications include fog harvesting, microfluidics, and biomolecule immobilization.