Application of TiO2 and Rh as cathode catalyst to boost the microbial electrosynthesis of organic compounds through CO2 sequestration. (February 2021)

• Record Type: Journal Article
• Authors: Das, Sovik; Das, Swati; Ghangrekar, M.M.
• Is Part Of: Process biochemistry. Volume 101(2021)
• Page Start: 237
• Page End: 246
• Publication Date: 2021-02
• Subjects: Bio-electrochemical system -- Cathode catalyst -- Carbon dioxide sequestration -- Microbial electrosynthesis -- Rh -- TiO2; Biochemical engineering -- Periodicals; Biotechnology -- Periodicals; Biochemistry -- periodicals; Biotechnology -- periodicals; Chemical Engineering -- periodicals; Génie biochimique -- Périodiques; Biotechnologie -- Périodiques; Biochemical engineering; Biotechnology; Periodicals; 660.63
• DOI: 10.1016/j.procbio.2020.11.017
• Languages: English
• ISSNs: 1359-5113

Abstract

Graphical abstract: Highlights: Rh and TiO2 were employed as cathode catalyst in microbial electrosynthesis (MES). Electrochemical analysis justified the application of Rh & TiO2 as cathode catalyst. Yield of acetate for MES with TiO2 as cathode catalyst was enhanced by 2.6 times. Coulombic efficiency was improved by 40 %, when TiO2 was used as cathode catalyst. Superior bacterial attachment for TiO2 coated cathode was depicted in SEM images. Abstract: Microbial electrosynthesis (MES) is a budding technology, where the principles of bioelectrochemical systems are employed to sequester CO2 and concomitantly produce value-added organic chemicals. The inferior production rate of organic chemicals in MES is a major roadblock in the real field application of this novel technology, which needs to be overcome by applying biocompatible metal-based cathode catalysts. Therefore in the present investigation, Rh and TiO2 microparticles were applied as cathode catalyst in MES and performance was compared based on production rate of organic chemicals and electrochemical parameters. The electrochemical properties of Rh and TiO2 were illustrated by employing cyclic voltammetry and electrochemical impedance spectroscopy, and reduction in overpotential associated with hydrogen evolution reaction was noticed for TiO2 coated electrode. Moreover, the production rate of acetate was also enhanced by 2.14 and 1.3 times due to the application of TiO2 (MES-Ti) and Rh (MES-Rh), respectively, as cathode catalyst in comparison to the MES operated without any cathode catalyst. Better bacterial attachment and more production of hydrogen were also observed for MES-Ti, which was fundamental to the improved performance of MES-Ti. Therefore, TiO2 can be deliberated as an effective cathode catalyst in MES to escalate its production rate.