Another online Group Meeting held this Thursday 17th September 2020. Good to catch up with everyone’s projects.
Fantastic online meeting today with colleagues at the National Battery Research Institute (NBRI) and the Minister of Research and Technology of Indonesia, who gave an insightful talk about Indonesian energy storage landscape and the UK-Indonesia joint activities. Glad to be part of the NBRI expert panel. Looking forward to many projects together.
Congratulations to Pavel, who passed his 30-month viva today, 14th September 2020. Well done Pavel!
Congratulations to Linh, who passed her 30-month viva on the 10th Sept 2020. Well done Linh!
Yesterday, we had the first group meeting since Ana’s maternity leave ended, with short update presentations from all members of the group! Great stuff!
Ana has been awarded a Newton Fund Institutional Links grant (ID 527320452) to conduct a project in collaboration with Colombia (Universidad Pontificia Bolivariana) and the team of Dr. Cristina Castro on Bacterial Nanocellulose for Energy Applications. Looking forward to starting this exciting project. Check out the abstract below!
Colombia is one of the world’s “megadiverse” countries, hosting close to 10% of the planet’s biodiversity. Therefore, bioeconomy is a field with a large potential for economic activities, mainly driven from new discoveries in the biological sciences. The last National Development Plan (PND, 2017) identified an economic growth strategy where biological resources and residual biomass must be managed in an efficient and renewable way to generate new products, processes and services with added value, as new levers for development. Our project aims to reuse the leftover of the fique natural fiber production (juice) from local producers (AGAVE S.A.S) in Antioquia, where close to 100 farmers of fique fibers sell this raw material at a price of $150 COP/kg for the production of sacks and cord. It is worth mentioning that only 4% of the fique plant is used for the extraction of fibers, leaving the remaining as waste. We will use the fique juice as a culture medium for the Komagataeibacter Medellinensis bacteria for the synthesis of bacterial nanocellulose, which will be further activated for energy storage applications, including lithium-ion batteries and supercapacitors. With this project, we will support local farmers, who will benefit from selling their agricultural waste to biomass companies, providing farmers a new source of income. The proposed collaboration involves Universidad Pontificia Bolivariana (UPB) and Queen Mary University of London (QMUL). Two research groups at UPB will join efforts for this project: new materials (GINUMA), energy and thermodynamics (GET). From QMUL, Dr. Jorge and Dr. Szilagyi will bring their experience in the application of biomass-derived materials as alternative energy compounds for storage and conversion. The knowledge of the UPB-QMUL team guarantees the project will be a success. We hope this institutional link fund will help us launch this collaboration further, including the development of an exchange program between institutions.
Ana has been awarded a Royal Society Grant (RGS\R1\201283) to develop 3D Printed Electrodes for Energy Conversion and Storage Technologies! Below the abstract of her project.
Sustainable energy production at an acceptable cost is key for its widespread application. At present, noble metals and metal oxides are the most widely used for electrocatalysis, but they suffer from low selectivity, poor durability and scarcity. The search for new materials and structures that use non noble metals is of paramount importance. 3D printing has received increasing attention in recent years, due to its flexibility and ability to design electrodes, which can incorporate electrocatalytic functional materials. This method enabled excellent control and tuneability of geometries and sizes at the micrometre scales while maintaining the characteristic advantages of their components. Another advantage of 3D printing technologies has to do with the ability to produce single parts consisting of multiple materials, even with printed gradients, which leads to highly tailored materials. However, the application of 3D printed electrodes in electrocatalysis is relatively new, only gaining momentum in the last years. Here I propose to use 3D printing to explore new electrode composites consisting of nanostructured graphene / transition metal electrocatalytic species for application in energy storage and conversion technologies. This research will lead to the development of a variety of electroactive composites, with different geometries and microstructures, and high electrocatalytic performance for batteries, fuel cells and water electrolyser systems. This research has the potential to truly transform the field of electrode design and expand the use of 3D printing techniques for the processing of new electrocatalytic architectures.
Adv. Funct. Mater. 2020, 2003035
A deeper understanding of the water‐splitting hydrogen evolution reaction (HER) mechanism during photocatalytic processes is crucial for the rational design of efficient photocatalysts. In particular, the HER mechanism promoted by multielement hybrid structures remains extremely challenging and elusive. Herein, an in situ photoelectrochemical/Raman measurement system is employed to monitor the HER mechanism of hybrid nanostructures under realistic working conditions via operando Raman spectra and linear‐sweep voltammetry curves. As a proof of concept, tunable composition transition metal dichalcogenides MoS2xSe2(1−x) nanosheets are used as a model photocatalyst to unveil the corresponding photocatalytic mechanism. The spectroscopic studies reveal that hydrogen atoms can be adsorbed to active sulfur and selenium atoms via intermediate species formed during the photocatalytic process. More importantly, the studies demonstrate that an exponential relationship exists between the number of reactive electrons and the Raman intensity of intermediate species, which can serve as a guideline to directly evaluate the HER performance in photocatalysts by comparing the Raman intensities of the intermediate species. As a simple, intuitive, and general analytical method, the designed operando Raman measurement approach provides a new tool for elucidating catalytic reaction mechanisms in a realistic and complex environment; and strategically improving H2 production performance of multielement photocatalysts.
Heat Diffusion‐Induced Gradient Energy Level in Multishell Bisulfides for Highly Efficient Photocatalytic Hydrogen Production
Insufficient light absorption and low carrier separation/transfer efficiency constitute two key issues that hinder the development of efficient photocatalytic hydrogen production. Here, multishell ZnS/CoS2 bisulfide microspheres with gradient distribution of Zn based on the heat diffusion theory are designed. The Zn distribution can be adjusted by regulating the heating rate and manipulating the diffusion coefficients of the different elements conforming the multishell photocatalyst. Because of the unique structure, a gradient energy level is created from the core to the exterior of the multishell microspheres, which effectively facilitates the exciton separation and electron transfer. In addition, stronger light absorption and larger specific surface area have been achieved in the multishell ZnS/CoS2 photocatalysts. As a result, the multishell ZnS/CoS2 microspheres with gradient distribution of Zn exhibit a remarkable hydrogen production rate of 8001 µmol g−1 h−1, which is 3.5 times higher than that of the normal multishell ZnS/CoS2 particles with well‐distributed Zn and 11.3 times higher than that of the mixed nonshell ZnS and CoS2 particles. This work demonstrates for the first time that controlling the diffusion rate of the different elements in the semiconductor is an effective route to simultaneously regulate morphology and structure to design highly efficient photocatalysts.
Congratulations Carlos! Well done!