• Energy Research

A facile strategy is proposed to finely manipulate the surface cation configuration of Ruddlesden–Popper perovskites, offering exceptional water oxidation performance in both setups of rotating disk electrodes and membrane electrode assemblies.

New reduced-temperature ceramic fuel cells with dual-ion conducting electrolyte and triple conducting double perovskite cathode.

In a world grappling with escalating energy needs, environmental concerns, and economic constraints, the transition to renewable energy becomes critical. This study delves into geothermal energy, a promising renewable source, to develop four distinctive tri-generation systems (producing power, heat, and freshwater) optimized for economic efficiency and investment returns. The primary focus is on assessing these systems through an innovative lens of economic viability, including net present value (NPV) and payback periods, alongside their thermodynamic performance. Notably, System B emerges as the most economically advantageous, boasting the shortest payback period of 3.65 years and the highest NPV of $2.38 million, while System C trails with the lowest NPV of $0.32 million. Additionally, System D, identified as optimally complementary, undergoes comprehensive optimization using advanced algorithms and machine learning, achieving notable efficiencies and cost-effectiveness in power output, exergy, and freshwater production. This study not only underscores the potential of geothermal tri-generation systems in meeting energy, heat, and water needs but also highlights their significant economic benefits and investment attractiveness, offering a compelling case for their adoption in sustainable energy strategies.

Inexpensive, highly active, durable bifunctional catalysts for both the hydrogen and oxygen evolution reaction (HER and OER) are fundamental for efficient energy conversion. It has been reported that a favorable electronic structure and high electrical conductivity contribute to obtaining superior electrocatalytic activity for perovskites; thus, effective strategies for engineering abundant beneficial factors must be explored to enhance HER and OER. Hence, we report a novel two-step solid-state phase reaction method combined with bulk doping for constructing perovskite La x Sr 1– x Fe 1–20 y Co 19y P y O 3−δ -ab (LSFCP-ab) with modest B–O length and high electrical conductivity. Induced by the strong charge redistribution via Fe 4+ -O 2– x -Co 3+ , abundant active sites (O 2 2– /O – , Fe 4+ , Co 3+ /Co 4+ ), moderate adsorption and desorption energies of the intermediates are obtained during OER and HER. Besides, the activated surface lattice oxygen O 2‑x could participate in the OER with lattice oxygen-mediated mechanism (LOM). Consequently, the optimal LSFCP-55 exhibits improved intrinsic OER and HER activity than that of La 0.2 Sr 0.8 FeO 3‑δ (LSF). Furthermore, the cell possesses a small cell voltage of 1.57 V with superior durability when it employed as the bifunctional catalyst in overall water splitting. This work provides a novel strategy to engineer beneficial electronic structures over perovskite oxides for sustainable energy conversion.

Developing a low-cost, and highly-efficient catalysts for improving oxygen reduction reaction (ORR) is imperative to the energy storage and conversion device. Here, we synthesized Ag/La0.6Sr0.4CoO3-delta, (Ag/LSC) composites by decorating LSC with Ag using the electroless technique. As a result, the LSC was homogenously overlaid with Ag nanoparticles. The derived Ag/LSC composites possessed a relatively higher specific surface area than pure LSC and Ag. The Co-O-Ag bonds in the composites contribute substantial electrons transferred from Ag to Co element, resulting in the unique electronic structures and strong electronic interaction between Ag and LSC. The significant improvements of ORR activity in alkaline solution at room temperature can be observed in Ag/LSC composites compared to the pure Ag and LSC. The composites with optimal Ag loading (50 wt%) showed best ORR activity among all the composites according to the half-wave potential and diffusion limiting current density. The presented strategy of silver surface modification via electroless process can provide effective routes for designing high performance metal oxide (e.g. perovskite) composite electrocatalysts. (C) 2018 The Electrochemical Society.

AbstractConstructing highly active electrocatalysts with superior stability at low cost is a must, and vital for the large‐scale application of rechargeable Zn–air batteries. Herein, a series of bifunctional composites with excellent electrochemical activity and durability based on platinum with the perovskite Sr(Co0.8Fe0.2)0.95P0.05O3−δ (SCFP) are synthesized via a facile but effective strategy. The optimal sample Pt‐SCFP/C‐12 exhibits outstanding bifunctional activity for the oxygen reduction reaction and oxygen evolution reaction with a potential difference of 0.73 V. Remarkably, the Zn–air battery based on this catalyst shows an initial discharge and charge potential of 1.25 and 2.02 V at 5 mA cm−2, accompanied by an excellent cycling stability. X‐ray photoelectron spectroscopy, X‐ray absorption near‐edge structure, and extended X‐ray absorption fine structure experiments demonstrate that the superior performance is due to the strong electronic interaction between Pt and SCFP that arises as a result of the rapid electron transfer via the PtOCo bonds as well as the higher concentration of surface oxygen vacancies. Meanwhile, the spillover effect between Pt and SCFP also can increase more active sites via lowering energy barrier and change the rate‐determining step on the catalysts surface. Undoubtedly, this work provides an efficient approach for developing low‐cost and highly active catalysts for wider application of electrochemical energy devices.

The metal nanoparticles (NPs)/perovskite hybrid prepared by in situ exsolution can synergistically catalyze the alkaline HER with high efficiency whereby the perovskite promotes water dissociation and metal NPs enable favorable hydrogen adsorption.

This research delves into the cutting-edge realm of solar-powered dual-temperature refrigeration, adhering to the 3E model emphasizing Energy, Economic, and Environmental considerations with a key focus on financial optimization. The study investigates the implementation of advanced refrigeration technologies, notably the integration of supercritical CO2 and ammonia cycles, tailored for dual-temperature applications. A distinctive aspect of this research is the strategic use of excess thermal energy, enhancing the efficiency of the refrigeration systems under varied climatic conditions. Central to the study is a thorough economic analysis aimed at reducing the Levelized Cost of Cooling (LCOC), while simultaneously enhancing the overall efficiency of the system. With the aid of the Engineering Equation Solver (EES) software, the system is modeled and the preliminary results indicate a promising decrease in cooling expenses (reaching to 90.25 $/GJ) alongside an increase in system efficiency (an improved efficiency of 33.17 %), with the total Coefficient of Performance (COP) demonstrating a significant advancement over traditional refrigeration models. This research underscores the effectiveness of harnessing solar energy in refrigeration technologies, contributing to financially viable and environmentally responsible cooling solutions. It provides valuable insights for the future development of refrigeration systems, which are both economically and environmentally sustainable.