echemdb 0.4.0

a Python library to work with the echemdb repository

The echemdb repository contains high quality experimental and theoretical data on electrochemical systems.

This echemdb module provides a Python library to interact with a database of frictionless datapackages containing electrochemical data following echemdb's metadata schema. Such a database can be generated from the data on echemdb.org or from local files.

Detailed installation instructions, description of the modules, advanced usage examples, including local database creation, are provided in our documentation.

Installation instructions

pip install echemdb

Python API

The currently available data shown on echemdb.org can be downloaded and stored in a database.

>>> from echemdb.cv.database import Database
>>> db = Database()

Filtering the database for entries having specific properties, e.g., containing Pt as working electrode material, returns a new database.

>>> db_filtered = db.filter(lambda entry: entry.system.electrodes.working_electrode.material == 'Pt')

A single entry can be retrieved with the identifiers provided on the website (see for example engstfeld_2018_polycrystalline_17743_f4b_1)

>>> entry = db['engstfeld_2018_polycrystalline_17743_f4b_1']

Each entry has a set of descriptors such as its source or the electrochemical system.

>>> entry.source # or entry['source']
{'citation key': 'engstfeld_2018_polycrystalline_17743', 'curve': 1, 'url': 'https://doi.org/10.1002/chem.201803418', 'figure': '4b', 'version': 1}

The data related to an entry can be returned as a pandas dataframe (values are provided in SI units).

>>> entry.df
           t	        E	       j
0	0.000000	-0.196962	0.043009
1	0.011368	-0.196393	0.051408
...

The dataframe can be returned with custom or original figure axes' units by rescaling the entry.

>>> entry.rescale({'E' : 'mV', 'j' : 'uA / m2'}).df
          t           E             j
0  0.000000 -196.961730  43008.842162
1  0.011368 -196.393321  51408.199892
...
>>> entry.rescale('original').df
          t         E         j
0  0.000000 -0.196962  4.300884
1  0.011368 -0.196393  5.140820
...

The units and reference electrodes can be found in the resource schema. The units are updated upon rescaling an entry.

>>> entry.package.get_resource('echemdb')['schema']
{'fields': 
[{'name': 't', 'unit': 's', 'type': 'number'}, 
{'name': 'E', 'unit': 'V', 'reference': 'RHE', 'type': 'number'}, 
{'name': 'j', 'unit': 'A / m2', 'type': 'number'}]}

The data can be visualized in a plotly figure:

>>> entry.plot()

License

The contents of this repository are licensed under the GNU General Public License v3.0 or, at your option, any later version.