Novel study on microbial fuel cells via a comprehensive bibliometric and dynamic approach.

Microbial fuel cells (MFCs) are eco-friendly and useful bioelectrical devices that harness the natural metabolisms of microbes to produce electrical power directly from organic materials. In this study, a bibliometric analysis is conducted to evaluate MFC research from 2001 to 2018 on the basis of the Science Citation Index Expanded database. Overall, MFC research has experienced a dramatic increase over last 18 years, with an exponential growth in the accumulated number of publications. Most publications are closely related to the industrialization and commoditization of MFCs, along with environmental issues, which are currently the biggest global challenges in MFC studies. A small proportion (4.34%) of the scientific journals published more than half (54.34%) of the total articles in the MFC field. Articles from the top 10 countries/regions accounted for the majority (83.16%) of the total articles, clearly indicating that advanced MFC technologies are currently dominated by these countries/regions. Moreover, an increasing number of MFC researchers are considering two-chamber and three-chamber MFC reactions. In particular, they are focusing on environmental technology instead of merely improving the efficiency of electricity generation. Materials research in the MFC field is still a popular area worldwide, and many researchers have focused on novel and eco-friendly cathode and anode developments. Meanwhile, only a few MFC studies are concerned with biological research.

Formulation of spinel based inkjet inks for protective layer coatings in SOFC interconnects.

In this study, inkjet printing technology was adopted for the application of protective layer coatings on metallic Solid Oxide Fuel Cell (SOFC) interconnects. The study highlights the potential of the inkjet printing process to fabricate aqueous-based protective layer coatings over ferritic stainless steels, a novel, very flexible, and low-cost approach to coating. The work presented focusses on the formulation of aqueous-based spinel particulate inks for the inkjet printing process using an electro-magnetic inkjet printer. An ink formulation route based on a two-stage ball milling technique was developed to produce a printable ink composition with Manganese Cobalt Oxide (MnCo2O4,MCO) and Manganese Cobalt Ferrite (MnCo1.8Fe0.2O4, MCF) as the coating materials. Stability of the ink suspensions and particle size distribution were studied and characterised using zeta and a particle size analysis, respectively. Flow properties of the inks were analysed using a conventional rheometer at shear rates 1 to 1000 s-1 and Piezo Axial Vibrator rheometer at higher shear rates (10-6 s-1). Finally, printability of the inks was assessed theoretically based on the Ohnesorge number, Z. The formulated MCO and MCF inks with ~ 25 wt% solid loading exhibited Z values of 4.17 and 6.77, satisfying the printability criteria of the inkjet inks. Printability of the inks was demonstrated by printing them on stainless-steel substrates. and printed layers were free of any visible defects after heat-treatment. The demonstrated ink formulation procedure provides a guide for inkjet inks development with respect to inkjet printer requirements. Furthermore, the outlined methodology can be employed to fabricate protective and other coatings for any kind of metallic components such as bipolar plates and heat-exchangers.

Plasma nitriding induced growth of Pt-nanowire arrays as high performance electrocatalysts for fuel cells.

In this work, we demonstrate an innovative approach, combing a novel active screen plasma (ASP) technique with green chemical synthesis, for a direct fabrication of uniform Pt nanowire arrays on large-area supports. The ASP treatment enables in-situ N-doping and surface modification to the support surface, significantly promoting the uniform growth of tiny Pt nuclei which directs the growth of ultrathin single-crystal Pt nanowire (2.5-3 nm in diameter) arrays, forming a three-dimensional (3D) nano-architecture. Pt nanowire arrays in-situ grown on the large-area gas diffusion layer (GDL) (5 cm(2)) can be directly used as the catalyst electrode in fuel cells. The unique design brings in an extremely thin electrocatalyst layer, facilitating the charge transfer and mass transfer properties, leading to over two times higher power density than the conventional Pt nanoparticle catalyst electrode in real fuel cell environment. Due to the similar challenges faced with other nanostructures and the high availability of ASP for other material surfaces, this work will provide valuable insights and guidance towards the development of other new nano-architectures for various practical applications.