Lyotropic Liquid Crystal Mediated Assembly of Donor Polymers Enhances Efficiency and Stability of Blade‐Coated Organic Solar Cells
This study reveals the concentration-dependent self-assembly of conjugated polymers, uncovering lyotropic liquid crystalline phases in several donor polymers. The extent of this self-assembly process, determined by the solvent drying dynamics during blade coating, gives distinct film morphologies that significantly impact the device efficiency and stability, offering a framework for optimizing performance through precise control of coating conditions and polymer assembly.
Abstract
Conjugated polymers can undergo complex, concentration-dependent self-assembly during solution processing, yet little is known about its impact on film morphology and device performance of organic solar cells. Herein, lyotropic liquid crystal (LLC) mediated assembly across multiple conjugated polymers is reported, which generally gives rise to improved device performance of blade-coated non-fullerene bulk heterojunction solar cells. Using D18 as a model system, the formation mechanism of LLC is unveiled employing solution X-ray scattering and microscopic imaging tools: D18 first aggregates into semicrystalline nanofibers, then assemble into achiral nematic LLC which goes through symmetry breaking to yield a chiral twist-bent LLC. The assembly pathway is driven by increasing solution concentration – a common driving force during evaporative assembly relevant to scalable manufacturing. This assembly pathway can be largely modulated by coating regimes to give 1) lyotropic liquid crystalline assembly in the evaporation regime and 2) random fiber aggregation pathway in the Landau–Levich regime. The chiral liquid crystalline assembly pathway resulted in films with crystallinity 2.63 times that of films from the random fiber aggregation pathway, significantly enhancing the T80 lifetime by 50-fold. The generality of LLC-mediated assembly and enhanced device performance is further validated using polythiophene and quinoxaline-based donor polymers.
A Functionalized 3D‐Printed Ti6Al4V “Cell Climbing Frame” Inspired by Marine Sponges to Recruit and Rejuvenate Autologous BMSCs in Osteoporotic Bone Repair
Inspired by marine sponges, the E7 peptide and EXOs-functionalized “Cell Climbing Frame” with a hierarchical porous structure specifically recruits and rejuvenates autologous BMSCs, and enhances cellular proliferation and osteogenic differentiation by down-regulating senescent-related genes and decreasing SASP factor release, thereby promoting the repair of osteoporotic bone defects and achieving robust multi-stage osseointegration.
Abstract
Osteoporosis, characterized by low bone mass and high fracture risk, challenges orthopedic implant design. Conventional 3D-printed Ti6Al4V scaffolds are mechanically robust but suffer from poor bone regeneration in osteoporotic patients due to stress shielding and cellular senescence. In this study, a functionalized 3D-printed Ti6Al4V “Cell Climbing Frame” is developed, aiming to adapt to the mechanical microenvironment of osteoporosis, effectively recruit and support the adhesion and growth of autologous bone marrow mesenchymal stem cells (BMSCs), while rejuvenating senescent cells for improved bone regeneration. Inspired by marine sponges, the processing accuracy limitations of selective laser melting (SLM) technology is broke through innovatively constructing a hierarchical porous structure with macropores and micropores nested within each other. Results demonstrate that the unique hierarchical porous scaffold reduces the elastic modulus, facilitates blood penetration, and enhances cell adhesion and growth. Further surface functionalization with E7 peptides and exosomes promotes the attraction and rejuvenation of BMSCs and boosts migration, proliferation, and osteogenic differentiation in vitro. In vivo, the functionalized “Cell Climbing Frame” accelerates bone repair in osteoporotic rats, while delaying surrounding bone loss, enabling robust multi-stage osseointegration. This innovation advances 3D-printed regenerative implants for osteoporotic bone repair.
From Salt in Water, Water in Salt to Beyond
Traditional aqueous electrolytes are limited by water's decomposition voltage (≈1.23 V). “Water-in-Salt” (WIS) electrolytes expand this stability window to 3 V, revolutionizing aqueous battery research. This review discusses the solvation structures, ion transport mechanisms, and interfacial properties of WIS electrolytes, highlighting advancements and future directions in aqueous electrolyte design.
Abstract
Traditional aqueous electrolytes have a limited electrochemical stability window due to the decomposition voltage of water (≈1.23 V). “Water-in-Salt” (WIS) electrolytes are developed, which expand the stability window of aqueous electrolytes from 1.23 to 3 V and sparked a global surge of research in aqueous batteries. This breakthrough revealed novel aspects of solvation structure, ion transport mechanisms, and interfacial properties in WIS electrolytes, marking the start of a new era in solution chemistry that extends beyond traditional dilute electrolytes and has implications across electrolyte research. In this review, the current mechanistic understanding of WIS electrolytes and their derivative designs, focusing on the construction of solvation structures is presented. The insights gained and limitations encountered in bulk solvation structure engineering is further discussed. Finally, future directions beyond WIS for advancing aqueous electrolyte design is proposed.
Unifying Electrochemically‐Driven Multistep Phase Transformations of Rutile TiO2 to Rocksalt Nanograins for Reversible Li+ and Na+ Storage
This work reveals the insight reason for the Li+ and Na+ storage performance of the rutile phase, which is determined by the electrochemically driven formed rocksalt nanograins. Importantly, the electrochemically in situ formed rocksalt phase has open diffusion channels for rapid Li+ or Na+ (de)intercalations through a solid-solution mechanism, which determines the pseudocapacitive, “mirror-like” cyclic voltammetry curves and excellent rate capabilities.
Abstract
Rutile titanium dioxide (TiO2(R)) lacks octahedral vacancies, which is not suitable for Li+ and Na+ intercalation via reversible two-phase transformations, but it displays promising electrochemical properties. The origins of these electrochemical performances remain largely unclear. Herein, the Li+ and Na+ storage mechanisms of TiO2(R) with grain sizes ranging from 10 to 100 nm are systematically investigated. Through revealing the electrochemically-driven atom rearrangements, nanosize effect and kinetics analysis of TiO2(R) nanograins during repeated cycling with Li+ or Na+, a unified mechanism of electrochemically-driven multistep rutile-to-rocksalt phase transformations is demonstrated. Importantly, the electrochemically in situ formed rocksalt phase has open diffusion channels for rapid Li+ or Na+ (de)intercalation through a solid-solution mechanism, which determines the pseudocapacitive, “mirror-like” cyclic voltammetry curves and excellent rate capabilities. Whereas, the nanosize effect determines the different Li+ and Na+ storage capacities because of their distinct reaction depths. Remarkably, the TiO2(R)-10 nm anode in situ turns into rocksalt nanograins after 30 cycles with Na+, which delivers a reversible capacity of ≈200 mAh g−1, high-rate capability of 97 mAh g−1 at 10 A g−1 and long-term cycling stability over 3000 cycles. The findings provide deep insights into the in situ phase evolutions with boosted electrochemical Li+ or Na+ storage performance.
Corrosion of metallic anodes in aqueous batteries
DOI: 10.1039/D5EE00075K, Review ArticleXuejin Li, Pengyun Liu, Cuiping Han, Tonghui Cai, Yongpeng Cui, Wei Xing, Chunyi Zhi
Aqueous metal batteries are advantageous in providing high energy density and excellent compatibility with various cathode materials, attracting more attention. However, the corrosion of metallic anodes seriously deteriorates the battery...
The content of this RSS Feed (c) The Royal Society of Chemistry
Tue 11 Feb 14:00: BSU Seminar: "The Lifebelt Particle Filter: a novel robust SMC scheme" This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/webinar/register/WN_WSJRt7ZlSTimpffcfcd6WA
Sequential Monte Carlo (SMC) methods can be applied to discrete State-Space Models on bounded domains, to sample from and marginalise over unknown random variables. Similarly to continuous settings, problems such as particle degradation can arise: proposed particles can be incompatible with the data, lying in low probability regions or outside the boundary constraints, and the discrete system could result in all particles having weights of zero. In this talk I will introduce the Lifebelt Particle Filter (LBPF), a novel SMC method for robust likelihood estimation in low-valued count problems. The LBPF combines a standard particle filter with one (or more) lifebelt particles which, by construction, lie within the boundaries of the discrete random variables, and therefore are compatible with the data. The main benefit of the LBPF is that only one or few, wisely chosen, particles are sufficient to prevent particle collapse. The LBPF can be used within a pseudo-marginal scheme to draw inferences on static parameters, θ, governing the system. In the talk I will also present an example of the use of the LBPF for the estimation of the parameters governing the death and recovery process of hospitalised patients during an epidemic.
This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/webinar/register/WN_WSJRt7ZlSTimpffcfcd6WA
- Speaker: Alice Corbella, University of Warwick
- Tuesday 11 February 2025, 14:00-15:00
- Venue: Large Seminar Room, East Forvie Building, Forvie Site Robinson Way Cambridge CB2 0SR..
- Series: MRC Biostatistics Unit Seminars; organiser: Alison Quenault.
Tue 11 Feb 14:00: BSU Seminar: "The Lifebelt Particle Filter: a novel robust SMC scheme" This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/webinar/register/WN_WSJRt7ZlSTimpffcfcd6WA
Sequential Monte Carlo (SMC) methods can be applied to discrete State-Space Models on bounded domains, to sample from and marginalise over unknown random variables. Similarly to continuous settings, problems such as particle degradation can arise: proposed particles can be incompatible with the data, lying in low probability regions or outside the boundary constraints, and the discrete system could result in all particles having weights of zero. In this talk I will introduce the Lifebelt Particle Filter (LBPF), a novel SMC method for robust likelihood estimation in low-valued count problems. The LBPF combines a standard particle filter with one (or more) lifebelt particles which, by construction, lie within the boundaries of the discrete random variables, and therefore are compatible with the data. The main benefit of the LBPF is that only one or few, wisely chosen, particles are sufficient to prevent particle collapse. The LBPF can be used within a pseudo-marginal scheme to draw inferences on static parameters, θ, governing the system. In the talk I will also present an example of the use of the LBPF for the estimation of the parameters governing the death and recovery process of hospitalised patients during an epidemic.
This will be a free hybrid seminar. To register to attend virtually, please click here: https://cam-ac-uk.zoom.us/webinar/register/WN_WSJRt7ZlSTimpffcfcd6WA
- Speaker: Alice Corbella, University of Warwick
- Tuesday 11 February 2025, 14:00-15:00
- Venue: Large Seminar Room, East Forvie Building, Forvie Site Robinson Way Cambridge CB2 0SR..
- Series: MRC Biostatistics Unit Seminars; organiser: Alison Quenault.
Tue 25 Feb 14:00: Downvoted to Oblivion: Censorship in Online, LGBTQ+ Communities
Online communities enable surveillance among LGBTQ ＋ users despite being used as safe spaces where users can explore their identity free from most online harms. Coercion, doxxing, and public outing are all examples of privacy violations faced. These are experienced when users fail to conform to fellow community members’ expected language and expressions of gender identity and sexuality. Current moderation systems fail to capture this peer surveillance because of the complexity of language and unspoken rules involved. This talk will explore how surveillance is enabled as well as its effects on the censorship of gender identity/expression in online LGBTQ ＋ communities.
Paper Link: https://discovery.ucl.ac.uk/id/eprint/10200690/
- Speaker: Kyle Beadle, UCL
- Tuesday 25 February 2025, 14:00-15:00
- Venue: Webinar & FW11, Computer Laboratory, William Gates Building..
- Series: Computer Laboratory Security Seminar; organiser: Tina Marjanov.
Fri 21 Feb 15:30: Title to be confirmed
Abstract not available
- Speaker: Steve Webb, Webb Yates Engineers, UK
- Friday 21 February 2025, 15:30-16:30
- Venue: Teaching Room (James Dyson Building).
- Series: Engineering Department Structures Research Seminars; organiser: Shehara Perera.
Fri 07 Feb 15:00: Population-Based Inference in Mechanics
Inferring model parameters from observational data of a physical system is the setup for many inverse problems. Solving these kinds of problems can give key insight into the state of a system for quantities that are not directly observable, such as material properties. In this talk, we discuss a population-based perspective on solving inverse problems where the data available comes from a collection of physical systems and we are interested in characterising the (indirectly observable) properties of these systems at a distributional level. We call this: calibrating priors from indirect data. Furthermore, we show how this can be accomplished while concurrently learning ML-based surrogates which capture the behaviour of the physical systems of interest.
- Speaker: Arnaud Vadeboncoeur, University of Cambridge
- Friday 07 February 2025, 15:00-16:00
- Venue: CivEng Conference Room (2nd Floor) (Civil Engineering Building).
- Series: Engineering Department Structures Research Seminars; organiser: Shehara Perera.
Li-Ion Nanorobots with Enhanced Mobility for Fast-Ion Conducting Polymer Electrolytes
DOI: 10.1039/D4EE05881J, PaperMingshen Tu, Ziheng Wang, Qionghai Chen, Zaiping Guo, Feifei Cao, Huan Ye
Ion transport in known polymer electrolytes highly depends on the segmental motion of polymer chains and they have low ionic conductivity due to a single-ion transport pathway. Novel design paradigms...
The content of this RSS Feed (c) The Royal Society of Chemistry
Iron clusters and single atom sites cooperatively promote bifunctional oxygen reaction activity in ultra-stable flexible zinc-air battery
DOI: 10.1039/D4EE05508J, PaperQi Liu, Panzhe Qiao, Di Shen, Ying Xie, Baoluo Wang, Tianyu Han, Hongtu Shi, Lei Wang, Honggang Fu
Enhancing the bifunctional activity of electrocatalysts for oxygen reduction/evolution reactions (ORR/OER), along with improving water retention in gel-polymer electrolytes, is essential for developing high-performance flexible zinc–air batteries (FZABs). Herein, we...
The content of this RSS Feed (c) The Royal Society of Chemistry
Tue 11 Feb 14:00: Symmetric Quantum Computation
A central challenge in quantum computing is to discern which types of problems allow for quantum algorithms that substantially outperform classical ones. Underlying this challenge is an even more fundamental question: what general characteristics of computational problems make them more (or less) amenable to quantum methods? In this talk I will present my personal attempts to make progress on this fundamental question.
I will introduce a new framework of quantum computation where the symmetries of the problem in consideration play a key role. This framework was developed with the view to elucidate the role of symmetries on quantum speedups, and forms a natural quantum extension of symmetric threshold circuits—a common core where multiple notions of symmetry in classical computation converge. I aim to motivate our computational model and show how it can go beyond the capabilities of its classical counterpart. Several open problems will be presented, which I hope can pave the way for future progress on my earlier question.
This talk is based on joint work with Tom Gur and Sergii Strelchuk.
- Speaker: Davi Castro-Silva (Cambridge)
- Tuesday 11 February 2025, 14:00-15:00
- Venue: Computer Laboratory, William Gates Building, Room SS03.
- Series: Quantum Computing Seminar; organiser: Tom Gur.
Tue 25 Feb 14:00: Title to be confirmed
Abstract not available
- Speaker: Kyle Beadle, UCL
- Tuesday 25 February 2025, 14:00-15:00
- Venue: Webinar & FW11, Computer Laboratory, William Gates Building..
- Series: Computer Laboratory Security Seminar; organiser: Tina Marjanov.
Wed 19 Mar 14:15: The Schubert variety of a hyperplane arrangement
I’ll tell you about some of my favorite algebraic varieties, which are beautiful in their own right, and also have some dramatic applications to algebraic combinatorics. These include the top-heavy conjecture (one of the results for which June Huh was awarded the Fields Medal), as well as non-negativity of Kazhdan—Lusztig polynomials of matroids.
- Speaker: Nicholas Proudfoot, University of Oregon
- Wednesday 19 March 2025, 14:15-15:15
- Venue: CMS MR13.
- Series: Algebraic Geometry Seminar; organiser: Dhruv Ranganathan.
Thu 03 Apr 16:00: 2024 Novo Nordisk Prize Lectures
Shankar and David will deliver the 2024 Novo Nordisk Lectures. Shankar’s will talk on Decoding DNA and David the applications of physical sciences to biomedicine, next generation DNA sequencing and beyond. This will be followed by a drinks reception hosted by the Novo Nordisk foundation.
- Speaker: Professors Sir Shankar Balasubramanian and Sir David Klenerman
- Thursday 03 April 2025, 16:00-17:30
- Venue: Dept of Chemistry, (BMS) Bristol Myers Squibb Lecture Theatre.
- Series: Chemistry Departmental-wide lectures; organiser: Balasubramanian-Admin.
Fri 04 Apr 10:30: Frontiers in Biophysics and Chemical Biology symposium
Funded by the Novo Nordisk Foundation and chaired by the 2024 Novo Nordisk Prize winners, Professors Sir Shankar Balasubramanian and Sir David Klenerman, this one day symposium brings together world leading scientists in the field of biophysics and chemical biology at the Yusuf Hamied Department of Chemistry.
The speakers are Professor Ed Boyden, MIT ; Professor Jason Chin, University of Cambridge; Professor Thomas Carrell from LMU , Munich; Professor Chuan He, University of Chicago; and Professor Xiaowei Zhang, Harvard University.
To register: https://www.eventbrite.co.uk/e/frontiers-in-biophysics-and-chemical-biology-tickets-1224872329109?aff=oddtdtcreator
- Speaker: Professor Ed Boyden, MIT; Professor Jason Chin, University of Cambridge; Professor Thomas Carrell from LMU, Munich; Professor Chuan He, University of Chicago; and Professor Xiaowei Zhang, Harvard University.
- Friday 04 April 2025, 10:30-17:00
- Venue: Dept of Chemistry, (BMS) Bristol Myers Squibb Lecture Theatre.
- Series: Chemistry Departmental-wide lectures; organiser: Balasubramanian-Admin.
Wed 12 Feb 14:00: Short-term, high-resolution sea ice forecasting with diffusion model ensembles
Sea ice plays a key role in Earth’s climate system and exhibits significant seasonal variability as it advances and retreats across the Arctic and Antarctic every year. The production of sea ice forecasts provides great scientific and practical value to stakeholders across the polar regions, informing shipping, conservation, logistics, and the daily lives of inhabitants of local communities. Machine learning offers a promising means by which to develop such forecasts, capturing the nonlinear dynamics and subtle spatiotemporal patterns at play as effectively—if not more effectively—than conventional physics-based models. In particular, the ability of deep generative models to produce probabilistic forecasts which acknowledge the inherent stochasticity of sea ice processes and represent uncertainty by design make them a sensible choice for the task of sea ice forecasting. Diffusion models, a class of deep generative models, present a strong option given their state-of-the-art performance on computer vision tasks and their strong track record when adapted to spatiotemporal modelling tasks in weather and climate domains. In this talk, I will present preliminary results from a IceNet-like [1] diffusion model trained to autoregressively forecast daily, 6.25 km resolution sea ice concentration in the Bellingshausen Sea along the Antarctic Peninsula. I will also touch on the downstream applications for these forecasts, from conservation to marine route planning, which are under development at the British Antarctic Survey (BAS). I welcome ideas and suggestions for improvement and look forward to discussing opportunities for collaboration within and beyond BAS .
[1] Andersson, Tom R., et al. “Seasonal Arctic sea ice forecasting with probabilistic deep learning.” Nature communications 12.1 (2021): 5124. https://www.nature.com/articles/s41467-021-25257-4
- Speaker: Andrew McDonald, University of Cambridge and British Antarctic Survey
- Wednesday 12 February 2025, 14:00-15:00
- Venue: BAS Seminar Room 2; https://ukri.zoom.us/j/96472472041.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Birgit Rogalla.
Lithium-selective “OR-gate” enables fast-kinetics and ultra-stable Li-rich cathodes for polymer-based solid-state batteries
DOI: 10.1039/D4EE05264A, PaperQin Wang, Yiming Zhang, Meng Yao, Kang Li, Lv Xu, Haitao Zhang, Xiaopeng Wang, Yun Zhang
The utilization of high-capacity lithium-rich layered oxide (LRLO) in lithium-ion batteries is hampered by its severe interface reactions and poor interface dynamics. Herein, an OG gate (OG) is constructed on...
The content of this RSS Feed (c) The Royal Society of Chemistry
Soft‐Actuated Cuff Electrodes with Minimal Contact for Bidirectional Peripheral Interfaces
Soft-actuated cuff electrodes (SACE) for bidirectional peripheral interfaces enable minimal and secure contact to the nerve through fluid injection-based soft actuation. A 3D bent structure can grasp and securely contact the nerves with only a little pressure (<1.21 gram-force). The SACE can achieve negligible damage to the nerve during recording of sensory and motor feedback signals with superior SNR and neuromodulation for long-term studies.
Abstract
Neural interfaces with embedded electrical functions, such as cuff electrodes, are essential for monitoring and stimulating peripheral nerves. Still, several challenges remain with cuff electrodes because sutured devices can damage the nerve by high pressure and the secured contact of electrodes with the nerve is hard to accomplish, which however is essential in maintaining electrical performance. Here, a sutureless soft-actuated cuff electrodes (SACE) that can envelop the nerve conveniently by creating a bent shape controlled upon fluid injection, is introduced. Moreover, fluid injection protrudes part of the device where electrodes are formed, thereby achieving minimized, soft but secure contact between the electrodes and the nerve. In vivo results demonstrate the successful recording and stimulation of peripheral nerves over time up to 6 weeks. While securing contact with the nerve, the implanted electrodes can preserve the nerve intact with no reduction in blood flow, thereby indicating only minimal compressive force applied to the nerve. The SACE is expected to be a promising tool for recording and stimulation of peripheral nerves toward bidirectional neuroprostheses.