Energy advances最新文献

In response to the growing demand for battery materials, researchers explore alternative resources with a focus on sustainability. Among these, organic electrode materials including porphyrins have emerged as promising candidates due to their advantageous properties, such as rapid charging capabilities and high energy densities. However, despite their potential, the precise charging mechanism of these alternatives remains elusive. To address this gap, our study delved into copper porphyrins, with a primary focus on [5,15-bis(ethynyl)-10,20-diphenylporphinato] copper(II) (CuDEPP). Employing synchrotron X-ray absorption spectroscopy in operando mode, we probed the evolution in chemical and electronic structure of Cu in CuDEPP. Our findings unequivocally demonstrate the participation of copper as a redox center during reversible charge storage, shedding light on its superior electrochemical performance. Furthermore, a combined approach involving extended X-ray absorption fine structure (EXAFS) studies and theoretical calculations provided deeper insights into the observed structural distortion during the charge storage process. Notably, our results support the hypothesis that redox processes, specifically those involving the aromatic porphyrin ring, drive the electrochemical activity of CuDEPP. In summary, our investigation offers important insights into the charging mechanism of copper porphyrins an essential step toward advancing sustainable organic materials for batteries.

This paper compares different power-to-methanol process configurations encompassing the electrolyser, adiabatic reactor(s) and methanol purification configurations. Twelve different power-to-methanol configurations based on direct CO₂ hydrogenation with H₂ derived from H₂O-electrolysis were modelled, compared, and analysed. A high temperature solid oxide electrolyser is used for hydrogen production. A fixed bed reactor is used for methanol synthesis. The aim of the paper is to give detailed comparison of the process layouts under similar conditions and select the best performing process configuration considering the overall methanol production, carbon conversion, flexibility, and energy efficiency. ASPEN PLUS® V11 is used for flowsheet modelling and the system architectures considered are the open loop systems where methanol is produced at 100 kton per annum and sold to commercial wholesale market as the final purified commodity. Further optimization requirements are established as targets for future work. Three options of power-to-methanol configuration with methanol synthesis from CO₂ hydrogenation are proposed and further evaluated considering process flexibility. From the evaluation, the series–series based configuration with three adiabatic reactors in series performed better in most parameters including the flexible load dependent energy efficiency.

The electroreduction of biomass-derived benzaldehyde (BZH) provides a potentially cost-effective route to produce benzyl alcohol (BA). This reaction competes with the electrochemical self-coupling of BZH to hydrobenzoin (HDB), which holds significance as a biofuel. Herein, we demonstrate the selectivity towards one or the other product strongly depends on the surface chemistry of the catalyst, specifically on its ability to adsorb hydrogen, as showcased with Cu₂S electrocatalysts. We particularly analyze the effect of surface ligands, oleylamine (OAm), on the selective conversion of BZH to BA or HDB. The effect of the electrode potential, electrolyte pH, and temperature are studied. Results indicate that bare Cu₂S exhibits higher selectivity towards BA, while OAm-capped Cu₂S promotes HDB formation. This difference is explained by the competing adsorption of protons and BZH. During the BZH electrochemical conversion, electrons first transfer to the C in the CO group to form a ketyl radical. Then the radical either couples with surrounding H⁺ to form BA or self-couple to produce HDB, depending on the H⁺ availability that is affected by the electrocatalyst surface properties. The presence of OAm inhibits the H adsorption on the electrode surface therefore reducing the formation of high-energy state H_ad and its combination with ketyl radicals to form BA. Instead, the presence of OAm promotes the outer sphere reaction for obtaining HDB.

Over the last few decades, research on glycosaminoglycans (GAGs) has primarily exploited their biological properties, since GAGs play pivotal roles in numerous key biological processes. Consequently, GAGs have attracted the interest of the biomaterial research community, with GAG-related materials finding increasing potential applications in classical areas such as drug delivery, tissue engineering, and wound healing. Notably, among the various reasons for their use is their capacity to conduct charges. Overall, GAGs exhibit conductivity values between 10⁻³ and 10⁰ mS cm⁻¹, comparable to those observed for several biological tissues. This appealing attribute has made GAGs prime candidates for the development of novel materials for bioelectrodes, biosensors, bioinks, electroceuticals, and other devices in the fast-growing fields at the interface between electronics and biology. Moreover, their use as conductive materials has extended beyond the realm of biosciences, with emerging reports of applications of GAGs in fuel cells, batteries, supercapacitors, or flexible electronic devices becoming increasingly common in the last few years. Coincidentally, the first review papers dedicated to the conductive properties of these materials have recently started to appear, providing yet another signal with regard to the growing interest in GAGs. We intend to present here an integrated and comprehensive outlook on the conductive properties of GAGs, both in the solid and solution states, from the initial studies carried out in the 1970s to the very latest developments, thus encompassing more than 40 years of research. Much of this work is rooted in biomaterial applications, making the reference to these applications unavoidable. Special emphasis will be given to the work produced for purposes other than the biomaterials field. We will mention the first attempts at exploring GAGs in energy devices and flexible electronics, and discuss the future of this class of biopolymers. On account of their electrochemical features, distinctive versatility, abundance, low cost, and eco-friendliness, GAGs offer exciting prospects for the development of energy-efficient and sustainable electroactive systems, which only depend on the researchers’ imagination and creativity.

A highly magnetic stable organogel electrolyte for supercapacitors was prepared via simple esterification using polyvinyl alcohol as the raw material. This organogel exhibits excellent mechanical properties: elongation (∼700%) and tensile strength (949.21 kPa), high flexibility, magnetism, and substantial specific capacitance (164.1 F g⁻¹). At a high scan rate of 50 mV⁻¹, the CV curve of this organic gel still maintains an ideal rectangle, showing high speed performance. It has broad prospects in the application of flexible electronic products.

Inorganic solid electrolytes are essential for developing safe and non-flammable all-solid-state batteries, with oxide-based ones having attracted attention owing to their excellent chemical stability. Recently, a new solid electrolyte material LiTa₂PO₈ (LTPO) was reported to have a bulk lithium-ion conductivity of 1.6 mS cm⁻¹ at room temperature, which is one of the highest among oxide solid electrolytes. However, oxide solid electrolytes tend to have a high grain boundary resistivity and must be formed into dense sintered pellets. In this study, different dense LTPO materials were synthesised by adjusting the size of the starting powder particles, and their ionic conductivities were systematically investigated. Counterintuitively, larger raw particles resulted in a lower grain boundary resistivity. This was attributed to the micromorphology of the sintered pellets. The grain boundary resistance varied by up to one order of magnitude under the investigated synthesis conditions, and the optimised total ionic conductivity (including the bulk and grain boundary contributions) of LTPO was 0.95 mS cm⁻¹ at 30 °C.

This review provides an overview of recent advances in the utilization of Ni-rich nickel–cobalt–manganese (NCM) oxides as cathode materials for Li-ion rechargeable batteries (LIBs). In the past decade, Ni-rich NCM cathodes have been extensively investigated because of their rational capacity and easy accessibility of constituent elements. However, huge capacity fading and irreversible structural disorder, associated with oxygen release, are the major limitations which hinder the desired electrochemical performance of these cathodes. The LIB performance can be improved through several strategies such as doping, coating, composite formation, microstructure manipulation and replacing the Mn ions. Attempts are also made to amend the crystal orientation and achieve additive-induced surface engineering of NCM cathodes. However, the practical application of high-performance LIBs demand an effective modification of the intrinsic properties of NCMs. Substandard thermal stability is another safety aspect to be resolved in the Ni-rich NCMs. However, efforts in this context are not enough. Apart from designing NCM cathodes, there are major issues such as cost-effectiveness, supply and demand for constituent elements, and the reuse of spent batteries, which hinder the realisation of LIBs with high electrochemical performance. Keeping in mind the current research interests, this review article presents concise and in-depth strategies to design NCM cathodes for future energy demands of mankind by considering the cost and Co abundance-related issues.

Hydrogen (H₂) has recently gained momentum as a promising clean energy alternative to fossil fuels. The intermittent nature of renewable energy, as the source of green H₂, necessitates temporary H₂ storage in subsurface geologic formations. To quantify storage potential and leakage risk, it is crucial to fully characterize subsurface H₂ transport behavior. This work aims to measure the diffusion of H₂ through relevant reservoir rocks, including two sandstones (Amherst Grey and Birmingham) and a limestone (Indiana). Breakthrough as a function of temperature is measured and used to calculate the effective diffusion coefficients and activation energy for diffusion at three different temperatures between 20 and 75 °C. Calculated diffusion coefficients are then used to estimate the subsurface plume size during storage in sandstone and limestone reservoirs. We observe that diffusive flow slightly expands plume size by up to 7%, and this effect is most pronounced in formations with low water saturation. While the use of cushion gas can maintain reservoir pressure and enhance injection efficiency, it can also enlarge H₂ plume and hinder the recovery process due to molecular diffusion if the cushion gas differs from H₂.

In this paper, two new 2D hybrid nanoheterostructures, namely AlN:CC:GaN:CC and AlN:CC:BN:CC, have been designed through density functional theory (DFT) methods. Their structural, electronic and optical properties have been sequentially investigated by first principles calculations. Phonon spectral dispersion calculations show that the novel materials have stable configurations. The results reveal that AlN:CC:GaN:CC is a direct band gap semiconducting material, with a band gap of 1.20 eV, which is desirable for optoelectronic applications. On the other hand, AlN:CC:BN:CC is an indirect band gap semiconducting nanoheterostructure with a band gap value of 0.98 eV, which is suitable for high-performance nanoelectronic device applications, energy conversion and energy storage. These materials have shown large optical absorption for visible and UV frequencies. They display anisotropic optical properties along the in-plane and out-of-plane directions. The results suggest the two novel 2D nanoheterostructures as promising candidates for potential applications in nano-electronics and opto-electronics.

pH-decoupling in aqueous redox flow batteries (ARFBs) represents a promising strategy for enhancing cell voltage and expanding the repertoire of redox pair combinations. Effective management of acid–base crossover and the implementation of cost-effective pH recovery methods are pivotal for long-term stability of pH-decoupling ARFBs. We introduce a pH-decoupling design integrated into a conventional single-membrane ARFB architecture. This approach reduces the area specific resistance while suppressing acid–base crossover to an acceptable level. We explore various electrolyte pairs, ranging from anions to cations, acids to bases, always dissolved to electrodepositing, showing the flexibility afforded by this design in selecting electrolyte compositions. Furthermore, we demonstrate the utility of proton-coupled electrochemical reactions as proton pumps, facilitating in situ or ex situ pH recovery within pH-decoupling batteries. Our findings potentially offer benefits including improved energy efficiency, increased areal power output, and decreased capital costs, thereby advancing the prospects for scalable and sustainable energy storage solutions.