Title of the dataset:
Data underlying the publication : Concentration-dependent effects of nickel doping on activated carbon biocathodes


Creators:
Konstantina-Roxani Chatzipanagiotou (ORCID 0000-0002-5565-9406)


Contributors:
L. Jourdin (ORCID 0000-0002-6572-1154)
J. H. Bitter (ORCID 0000-0002-4273-9968)
D.P.B.T.B. Strik (ORCID 0000-0003-0591-682X)


Related publication:
Concentration-dependent effects of nickel doping on activated carbon biocathode (https://doi.org/10.1039/D1CY02151F)


Description:
Investigation of the combination of a metal electrocatalyst (nickel nanostructures on activated carbon) with a bio-electrocatalyst (mixed anaerobic microbial consortium) for CO2 electroreduction. Biological and abiotic electrochemical experiments, in duplicate, with 3 types of electrodes: without nickel catalyst, with low nickel loading (0.01% wt.), and with high nickel loading (5% wt.). Data includes current density and charge during chronoamperometry experiments, concentration of liquid and gas compounds, optical density, NH4+ nutrient concentration, pH of catholyte, electron recovery calculations, dissolved metal concentration (measured with ICP), and microbial community composition from planktonic samples (characterized with NGS).


Keywords:
Microbial Electrosynthesis Systems
biocathode BES
nickel electrocatalyst
hydrogen evolution electrocatalyst
co-catalytic system


This dataset contains the following files:
AC-Ni bio reactor data UPLOAD.xlsx 
This file includes detailed raw data (potentiostat data, concentration of liquid compounds and NH4+, optical density, pH) and daily handling of bioreactors (i.e., sampling volumes, CO2 feeding regime) of bioelectrochemical experiments. Raw data on electric current and concentration of liquid compounds are used to calculate the electron recovery. Sampling volumes and addition of fresh growth medium are used to calculate dilution of concentrations after taking samples. Several graphs are included, for better visualization of data.

AC-Ni gas & abiotic UPLOAD.xlsx
This file includes detailed raw data (potentiostat data, concentration of gas compounds) and daily handling of biological and abiotic reactors (i.e., sampling volumes, CO2 feeding regime). Raw data on electric current and concentration of gas compounds are used to calculate the electron recovery. Several graphs are included, for better visualization of data.

AC-Ni ICP UPLOAD.xlsx
This file includes detailed raw data on the concentration of dissolved metal ions during abiotic and biological electrochemical experiments, determined with Inductively coupled plasma - optical emission spectrometry. This file further contains the metal concentration measured after acid digestion of activated carbon samples, and the amount of activated carbon per electrode, which are used to calculate the actual metal loading of the used electrodes, and the total amount of nickel added per reactor (in the form of nickel impregnated on activated carbon electrodes). 

AC-Ni NGS UPLOAD.xlsx
This file contains raw data from Next Generation Sequencing analysis performed on planktonic samples from experimental bioreactors, as well as a sample of the inoculum used at the start of the experiments. Data is shown on the family level (L5) and the genus level (L6). The most dominant taxa are used for statistical analysis (i.e., calculation of average and standard deviation), and several graphs are included, for better visualization of data.

AC-Ni potentiostat UPLOAD.xlsx
This file contains raw data of current (in mA) recorded by the potentiostat during biological experiments. Based on the electrode volume (in cm3), the current density is calculated (in mA/cm3). Several graphs are included, for better visualization of data.


Explanation of variables:
To the best of our effort, all units of measurement (and a description of the variable) are given within the top 2 lines of every column in each excel file. 
All liquid and gas volumes are reported in ml.
Current is reported in mA, current density is reported in mA/cm3, and Charge is reported in Coulombs (C). 
Concentration of dissolved compounds, such as C1 (formate), C2 (acetate) and NH4+ are given in mg/L, and converted to mmol/L when needed for calculations of electron recovery.
Concentration of gas compounds is given in % (i.e., the raw data generated by the gas chromatography software) and converted to ml of gas and mmol of gas, based on the total headspace volume for each reactor, using the ideal gas law.  
Concentration of dissolved metal ions is given in μg/L.
 

Methods, materials and software:
All equipment and software used for data collection is reported in the experimental section of this publication.
All data processing was performed with Microsoft Excel, with the exception of the correlation analysis reported in Table 3 of the publication, which was performed with SPSS (as stated in the experimental section). 


This dataset is published under the CC BY (Attribution) license.
This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, so long as attribution is given to the creator.

