Comparison of Activation Methods for 3D-Printed Electrodes for Microbial Electrochemical Technologies

Raúl M Alonso,Isabel San Martín,Antonio Morán,Adrián Escapa

doi:10.3390/app12010275

Abstract

Three-dimensional printing could provide flexibility in the design of a new generation of electrodes to be used in microbial electrochemical technologies (MET). In this work, we demonstrate the feasibility of using polylactic acid (PLA)/graphene—a common 3D-printing material—to build custom bioelectrodes. We also show that a suitable activation procedure is crucial to achieve an acceptable electrochemical performance (plain PLA/graphene bioanodes produce negligible amounts of current). Activation with acetone and dimethylformamide resulted in current densities similar to those typically observed in bioanodes built with more conventional materials (about 5 Am−2). In addition, the electrodes thus activated favored the proliferation of electroactive bacteria.

Highlights

Activation Methods for 3D-PrintedThe advance of a multidisciplinary field like bioelectrochemistry runs parallel to that of other fields of knowledge, such as microbiology, electrochemistry, materials science or manufacturing engineering, in an interdependent manner [1]
In accordance with Gusmão et al [12], we observed that the activation procedure greatly a polarization potential of 0.250 V vs. Ag/AgCl (3.5 M)
This study demonstrates the suitability of polylactic acid (PLA)/graphene as an electrode material for

Summary

Introduction

Activation Methods for 3D-PrintedThe advance of a multidisciplinary field like bioelectrochemistry runs parallel to that of other fields of knowledge, such as microbiology, electrochemistry, materials science or manufacturing engineering, in an interdependent manner [1]. The appearance of new materials, frequently referred to as nanomaterials, has opened new perspectives in the development of microbial electrochemical technologies (MET), which could contribute to overcoming global challenges in sustainable energy and waste management, as numerous publications have already shown [2,3,4,5]. Another technological breakthrough capable of evolving METs is additive manufacturing (AM)—commonly known as 3D printing—which has led to a paradigm shift in manufacturing engineering and has revealed potential in the development of functional MET prototypes [6]. A recently developed line of research is exploiting the advantages of polymer electrodes made by AM in electrochemical applications such as sensing [8,9] and energy storage [10,11]

Objectives

Methods

Results