Recent Advances In Stabilization Research Articles

FA/Cs-based mixed Pb–Sn perovskite solar cells: A review of recent advances in stability and efficiency

Perovskite solar cells (PSCs) have gained widespread attention due to their impressive optoelectronic properties, extraordinarily high efficiency, and low-cost manufacturing processes. PSCs are poised to usher in a new era of clean energy production. However, the use of methylammonium (MA) as the A-site cation in PSCs may result in poor thermal and atmospheric stability, limiting their potential for widespread commercialization. On the other hand, the most extensively studied perovskite systems with respect to B-site cations are pure Pb-based compositions due to their high device performance demonstrated to date. However, mixed Pb–Sn compositions can offer optimal bandgap energies for single-junction solar cells, suggesting the promise of future efficiency improvements. Thus, this review focuses on mixed Pb–Sn perovskite solar cells that use formamidinium (FA) or mixed cations of FA and cesium (Cs) without MA. These materials have bandgap energies suitable for use in either single-junction or multi-junction solar cells and show improved stability compared to their MA-based counterparts. We discuss the structural and optoelectronic properties of FA/Cs-based Pb–Sn perovskites and the efforts to improve their solar cell performance and stability through additive engineering, process optimization, and structural modifications. Our review highlights the potential for FA/Cs-based mixed Pb–Sn perovskites as a more stable and efficient alternative for future commercial applications of PSCs.

Recent Advances in Stabilization of Sodium Metal Anode in Contact with Organic Liquid and Solid‐State Electrolytes

Sodium (Na) metal is considered as the promising anode for next‐generation high‐energy‐density Na‐metal batteries owing to its highest specific capacity and lowest electrochemical potential among all Na‐based anode candidates. However, the Na metal anode suffers from considerable volume change, nonuniform Na deposition, and an unstable electrode–electrolyte interface, which result in rapid capacity fade and poor cycling stability, hampering its practical application. To tackle aforementioned issues, many strategies have been developed to accommodate and guide Na nucleation/growth as well as stabilize the interface, including structure stabilization by applying 3D host materials, electrolyte modification and interface engineering to form stable interfaces and guide the Na deposition, etc. The present review is intended as a guideline through the fundamental challenges affecting the performance of Na metal anodes along with corresponding mitigation strategies. Moreover, the specific mechanisms for stabilizing Na metal anodes are discussed in detail. Apart from the stabilization of the Na metal anode in contact with liquid electrolytes, attention has also been paid to the review of stabilization of the Na metal anode in contact with solid‐state electrolytes. Furthermore, unresolved challenges and promising perspectives for stable Na metal anodes in practical applications are presented.

Recent Advances in Stability and Failure Mechanisms of Landslide Dams

Numerous landslide dams have been induced in recent years as a result of frequent earthquakes and extreme climate hazards. Landslide dams present serious threats to lives and properties downstream due to potentially breaching floods from the impounded lakes. To investigate the factors influencing the stability of landslide dams, a large database has been established based on an in-depth investigation of 1,737 landslide dam cases. The effects of triggers, dam materials, and geomorphic characteristics of landslide dams on dam stability are comprehensively analyzed. Various evaluation indexes of landslide dam stability are assessed based on this database, and stability evaluation can be further improved by considering the dam materials. Stability analyses of aftershocks, surges, and artificial engineering measures on landslide dams are summarized. Overtopping and seepage failures are the most common failure modes of landslide dams. The failure processes and mechanisms of landslide dams caused by overtopping and seepage are reviewed from the perspective of model experiments and numerical analyses. Finally, the research gaps are highlighted, and pathways to achieve a more complete understanding of landslide dam stability are suggested. This comprehensive review of the recent advances in stability and failure mechanisms of landslide dams can serve as a key reference for stability prediction and emergency risk mitigation.

Recent Advances in Stability of Carbon‐Based Anodes for Potassium‐Ion Batteries

AbstractThe commercialization of potassium‐ion batteries requires promising anodes with excellent reversible capacity and cycle stability. Graphite anodes have attracted extensive research owing to the formation of stable intercalation compounds, which also helps to focus attention on low‐cost carbon‐based anodes. However, the slow diffusion of potassium ion (K+) and structural damage of graphite caused by large size may lead to capacity decay. Herein, the modification strategies have been summarized, including microstructure regulation, heteroatom doping and building stable solid electrolyte interphase. And the opportunities and challenges faced by these improvement methods are proposed. Meanwhile, carbon‐based materials used as hosts or conductive carriers to improve the performance of other anodes are also summarized.

Recent advances in stability of organic solar cells

Organic solar cells have achieved rapid development over the last few years, benefitting from the emerging of new non-fullerene acceptors (NFAs). The reported power conversion efficiency of OSCs has achieved over 18% up to now, however, the inferior stability issue restricts its commercialization, which stimulates the interest of scientists to explore it in-depth as well. Thus, we discuss the mechanisms of the instability in OSC devices, comprehensively summarize the progress of OSC stability in recent years and propose a series of solutions that improve the stability in this review. Although the highly-stable OSCs with extrapolated lifetime over several decades have been reported, the biggest drawback of them is the insufficient PCE. Thereby, investigating efficient OSCs with high-stability is required. We expect this review can provide some guidelines to address the instability of OSCs for feasible commercialization in the future.

Recent advances in stabilization of mode-locked quantum dash lasers at 1.55 µm by dual-loop optical feedback

This paper reports the effectiveness of a variety of single- and dual-loop optical feedback arrangements on stability of self-mode-locked two-section quantum dash lasers emitting at ≈1.55 µm and operating at 21 GHz repetition rate. We describe reduction of RF linewidth and timing jitter using five distinct schemes, including single and dual loops with symmetric and asymmetric lengths, and with balanced and unbalanced feedback ratios. All feedback schemes described are effective in stabilizing the pulse trains from SML QDash lasers, but some require precisely tuned resonance between loop delay and laser cavity. We show balanced asymmetric dual-loop optical feedback is the most robust, cost-effective and low-noise method to stabilize and control pulses from mode-locked lasers and optoelectronic oscillators.

Overview of recent advances in stability of linear systems with time‐varying delays

This study provides an overview and in-depth analysis of recent advances in stability of linear systems with time-varying delays. First, recent developments of a delay convex analysis approach, a reciprocally convex approach and the construction of Lyapunov–Krasovskii functionals are reviewed insightfully. Second, in-depth analysis of the Bessel–Legendre inequality and some affine integral inequalities is made, and recent stability results are also summarised, including stability criteria for three cases of a time-varying delay, where information on the bounds of the time-varying delay and its derivative is totally known, partly known and completely unknown, respectively. Third, a number of stability criteria are developed for the above three cases of the time-varying delay by employing canonical Bessel–Legendre inequalities, together with augmented Lyapunov–Krasovskii functionals. It is shown through numerical examples that these stability criteria outperform some existing results. Finally, several challenging issues are pointed out to direct the near future research.

Stabilized Lipid Films in Electrochemical Biosensors

AbstractLipid membrane based electrochemical biosensors have been exploited for the last 40 years. However, a major obstacle that limited their applications and commercialization was their fragility. Recent advances in stabilization of lipid membranes have tremendously increased the number of publications in the last 5 years. The objective of the present article is to present procedures for the stabilization of lipid film biosensors and recent advances in their analytical uses. These novel devices are used as chemo‐ and biosensors for the quantification of environmental contaminants and food toxicants. Recent research is directed to the construction of a portable mini electrochemical device that will be commercialized and readily be used by non‐skilled personnel for in the field measurements.