1. Low-cost, facile droplet modification of screen-printed arrays for internally validated electrochemical detection of serum procalcitonin
Paulo Roberto de Oliveira, Robert D Crapnell, Alejandro Garcia-Miranda Ferrari, Phatsawit Wuamprakhon, Nicholas J Hurst, Nina C Dempsey-Hibbert, Montree Sawangphruk, Bruno Campos Janegitz, Craig E Banks
Biosensors and Bioelectronics, 2023, 228, 115220
DOI: https://doi.org/10.1016/j.bios.2023.115220
Abstract: This manuscript presents the design and facile production of screen-printed arrays (SPAs) for the internally validated determination of raised levels of serum procalcitonin (PCT). The screen-printing methodology produced SPAs with six individual working electrodes that exhibit an inter-array reproducibility of 3.64% and 5.51% for the electrochemically active surface area and heterogenous electrochemical rate constant respectively. The SPAs were modified with antibodies specific for the detection of PCT through a facile methodology, where each stage simply uses droplets incubated on the surface, allowing for their mass-production. This platform was used for the detection of PCT, achieving a linear dynamic range between 1 and 10 ng mL−1 with a sensor sensitivity of 1.35 × 10−10 NIC%/ng mL−1. The SPA produced an intra- and inter-day %RSD of 4.00 and 5.05%, with a material cost of £1.14. Internally validated human serum results (3 sample measurements, 3 control) for raised levels of PCT (>2 ng mL−1) were obtained, with no interference effects seen from CRP and IL-6. This SPA platform has the potential to offer clinicians vital information to rapidly begin treatment for “query sepsis” patients while awaiting results from more lengthy remote laboratory testing methods. Analytical ranges tested make this an ideal approach for rapid testing in specific patient populations (such as neonates or critically ill patients) in which PCT ranges are inherently wider. Due to the facile modification methods, we predict this could be used for various analytes on a single array, or the array increased further to maintain the internal validation of the system.
2. Exploring the Role of the Connection Length of Screen-Printed Electrodes towards the Hydrogen and Oxygen Evolution Reactions
Phatsawit Wuamprakhon, Alejandro Garcia-Miranda Ferrari, Robert D Crapnell, Jessica L Pimlott, Samuel J Rowley-Neale, Trevor J Davies, Montree Sawangphruk, Craig E Banks
Sensors, 2023, 23, 1360
DOI: https://www.mdpi.com/1424-8220/23/3/1360
Abstract: Zero-emission hydrogen and oxygen production are critical for the UK to reach net-zero greenhouse gasses by 2050. Electrochemical techniques such as water splitting (electrolysis) coupled with renewables energy can provide a unique approach to achieving zero emissions. Many studies exploring electrocatalysts need to “electrically wire” to their material to measure their performance, which usually involves immobilization upon a solid electrode. We demonstrate that significant differences in the calculated onset potential for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) can be observed when using screen-printed electrodes (SPEs) of differing connection lengths which are immobilized with a range of electrocatalysts. This can lead to false improvements in the reported performance of different electrocatalysts and poor comparisons between the literature. Through the use of electrochemical impedance spectroscopy, uncompensated ohmic resistance can be overcome providing more accurate Tafel analysis.
3. Sustainable Reuse and Recycling of Spent Li-ion batteries from Electric Vehicles: Chemical, Environmental and Economical Perspectives
Kanit Hantanasirisakul, Montree Sawangphruk
Global Challenges, 2023
DOI: https://onlinelibrary.wiley.com/doi/full/10.1002/gch2.202200212
Abstract: The rapidly increasing adoption of electric vehicles (EVs) worldwide is causing high demand for production of lithium-ion batteries (LIBs). Tremendous efforts have been made to develop different components of LIBs in addition to design of battery pack architectures as well as manufacturing processes to make better batteries with affordable prices. Nonetheless, sustainable use of LIBs relies on the availability and cost of rare metals, which are naturally concentrated in a few countries. In addition, toxic electrolytes used in LIBs pose concerns on environmental impacts if LIBs are not handled properly after decommissioned from EVs. Therefore, it is paramount to realize effective utilization of spent LIBs, where their remaining capacities can be reused in less demanding applications. Finally, electrode materials and other valuable components of LIBs can be recovered via recycling, completing their circular life cycle. In this review, available options of LIBs after their retirement from EV applications, including battery second use, repair of electrode materials by direct regeneration, and material recovery by hydrometallurgical or pyrometallurgical processes are discussed. Throughout the review, the discussion is based around current available technologies, their environmental impacts, and economic feasibility as well as provided examples of pilot and industrial scale adoption of the processes.
4. Reducing Intrinsic Drawbacks of Ni-rich Layered Oxide with a Multifunctional Materials Dry-Coating Strategy
Nichakarn Anansuksawat, Poraman Chiochan, Kan Homlamai, Nattanon Joraleechanchai, Worapol Tejangkura, Montree Sawangphruk
Journal of Power Sources, 2023, 554, 232324
DOI: https://doi.org/10.1016/j.jpowsour.2022.232324
Abstract: Herein, we introduce a multifunctional materials dry coating strategy on LiNi0.8Mn0.1Co0.1O2 (NMC811) at 1 wt% with a thickness of ca. 100 nm. The materials included high chemical stable Al2O3 (0.33 wt%) to reduce parasitic reactions, high electrical carbon black (0.33 wt%) to reduce internal charge transfer resistance, and high ionic conductive Li7La3Zr2O12 (0.33 wt%) to enhance Li+ diffusion. The scalable dry coating mechanofusion used can also generate a smooth surface of spherical NMC811 particles enhancing its stability. With an exceptional property of mixed multi-functional materials, the cell of encapsulated NMC811 can perform up to 1000 cycles with 80% capacity retention. Whilst the pristine NMC811 cell can maintain only 39%. The coated NMC811 provides a two-fold specific capacity at a high C-rate (2.0C) compared to the pristine one. Moreover, it also offers excellent safety based on the UN38.3 standard at 18650 cylindrical cells. This multifunctional coating concept may lead to the further development of high-performance Li-ion batteries.
5. Utilizing the built-in electric field of pn heterojunction to spatially separate the photogenerated charges in C, N co-doped Co3O4/CdS photocatalysts
Tingzhen Chen, Chengwu Yang, Saravanan Rajendran, Montree Sawangphruk, Xinyu Zhang, Jiaqian Qin
Fuel, 2023, 331, 125594
DOI: https://doi.org/10.1016/j.fuel.2022.125594
Abstract: As one of the most effective strategies for the storage and utilization of solar energy, the development of photocatalytic technology has received extensive attention. The core work, the design and modification of photocatalysts, is very significance. Herein, we prepared C, N co-doped Co3O4 (CN-CoO) by a simple method and composited it with CdS to form CN-CoO/CdS p-n type heterojunctions. The prepared materials are characterized by numerous tests, such as XRD, SEM, TEM, XPS, and photoelectrochemical measurement. Due to the excellent electrochemical performance of CN-CoO and the built-in electric field in CN-CoO/CdS, the efficient separation of photogenerated charges is realized. Compared with CdS (1.11 ns), the average carrier lifetimes of the 15%CN-CoO/CdS (1.63 ns) is prolonged, which enhances photocatalytic hydrogen evolution activity of the composite materials. The hydrogen evolution rate of the optimal 15%CN-CoO/CdS is 6.78-fold greater than that of pristine CdS, and is as high as 64.36 mmol·g−1·h−1. Meanwhile, the 15%CN-CoO/CdS exhibits outstanding chemical stability after cyclic hydrogen production experiment for 30 h, and its apparent quantum efficiency (AQE) reaches 27.47% under monochromatic light at 405 nm. In addition, the formation process and photocatalytic hydrogen evolution mechanism of the CN-CoO/CdS p-n type heterojunctions are analyzed and discussed. This work provides a new idea for the construction of efficient photocatalytic heterojunctions through the modification and combination of semiconductors.
