*1.3.2 The field of a thousand names*

It is quite difficult to find specific information about this new area of study. One of the reasons is that this field has not been properly established. Another

### **Figure 4.** *Electrode materials and catalysts for photobioelectrochemical systems.*

one is that the terminology used to address photobioelectrochemical devices is not standardized. Photobioelectrochemical systems are referred to with several different terms in the articles available in the scientific literature. **Table 1** contains some examples where different prefixes and suffixes are used based on physical characteristics or functionalities that these devices present.

This mix of prefixes and suffixes are also used to name each combination of electrode materials, as well as functional capabilities. For instance, **Table 2** enlists 16 different names that were used to refer to the same set of microbial bioanode and photocathode electrodes in 26 articles, out of 76 that reported any type of photobioelectrochemical system. While some researchers use dashes to build the terms, others make a brief description of the devices. For the biological components only the prefix bio and the word microbial are implemented, which is easy to remember;


### **Table 1.**

*Current terms used for referring to Photobioelectrochemical systems.*


**Table 2.**

*The terminology used to define a photobioelectrochemical device with bioanode and photocathode materials.*

*Microbial Photobioelectrochemical Systems: A Scoping Review DOI: http://dx.doi.org/10.5772/intechopen.99973*

however, for the photoelectrode components, the prefixes photo and/or electro are coupled with verbs such as assistance, catalysis, driving, and synthesis. These prefixes are usually substituted by the word semiconductor to refer to these electrodes. Also, some papers describe the devices, while others create a unique name for them.

The wide variety of terms used to define photobioelectrochemical systems further increases the difficulty of making a literature review. This work aimed to compile as much information on this field as possible, but there are probably so many combinations of keywords that some of them may be missed even with a systematic search process like the one used here.
