Dataset from the manuscript: 
"Promoting photocatalytic activity of NH2-MIL-125(Ti) for H2 evolution reaction through creation of TiIII and CoI based proton reduction sites".

Authors: Vitalii Kavun,*(a) Evgeny Uslamin,(b) Bart van der Linden,(b) Stefano Canossa,(c) Andrey Goryachev,(b) Emma E. Bos,(b) Jara Garcia Santaclara,(b) Grigory Smolentsev,(d) Eveliina Repo,(a) Monique A. van der Veen*(b)
(a) Department of Separation Science, LUT University, FI-53850, Lappeenranta, Finland; 
(b) Department of Chemical Engineering, Delft University of Technology, 2629 HZ, Delft, The Netherlands;
(c) Department of Nanochemistry, Max Planck Institute for Solid State Research, 70569, Stuttgart, Germany;
(d) Paul-Scherrer Institute, CH-5232, Villigen PSI, Switzerland.


*Corresponding authors: V. Kavun and M. A. Van der Veen
Contact Information: vitalii.kavun@gmail.com, M.A.vanderVeen@tudelft.nl
Delft University of Technology - Faculty of Applied Sciences
Building 58, room E2.180
Van der Maasweg 9
2629HZ Delft
The Netherlands

***General Introduction***
This dataset contains raw characterization data related to two synthesized Metal-organic Frameworks' (MOFs) phototcatalysts and is a part of Vitalii Kavun's PhD Thesis project (2019-2023). It is made public for other researchers to check and use this data in their own work.

The data was collected in the Delft University of Technology and Swiss Light Source at the Paul Scherrer Institute. 

***Purpose of this research***
The purpose of these experiments was to investigate the structure and performance of two MOF-based photocatalysts - NH2-MIL-125(Ti) and single-Co-site embedded Co@NH2-MIL-125(Ti), upon visible light exposure.

***Characterization techniques***
Powder X-ray Diffraction (PXRD) patterns were acquired using a Bruker D8 Advance diffractometer with Co Kα source (λ = 1.7889 Å, 35 kV and 40 mA) and Lynxeye position sensitive detector. Diffractograms were collected with 2theta ranging from 5º to 50º at a scanning rate of 0.02º s-1, a motorized fixed-divergent slit 0.3º and an exposure time of 0.7 seconds per step.

N2 physisorption experiments were performed using a Micromeritics Tristar II 3020 at 77 K. Prior to sorption measurements, samples were dried overnight at 150 ºC under N2 flow. The data presented in the manuscript was processed using an open-source BETSI tool.[1]

Transmission Electron Microscope (TEM) measurements were performed by using a JEOL JEM-1400 Plus machine operating at an acceleration voltage of 120 kV. The samples were mounted on the carbon-coated copper grid.

Time-resolved pump-flow-probe X-ray Absorption Spectroscopy (XAS) measurements were performed at the SuperXAS beamline of the Swiss Light Source at the Paul Scherrer Institute. The concept of the experiment setup has been described in detail elsewhere.[2] In a typical measurement, 235 mg of Co@NH2-MIL-125(Ti) was suspended in a sample vial containing a mixture of 70 mL acetonitrile, 14 mL TEA and 1.5 mL deionized water, and sonicated for 30 min. Before the measurement, the sample jet chamber was purged with N2 for at least 15 min to deoxygenate the system. The sample solution was then pumped through a nozzle with a 1 mm diameter at a velocity of 4.32 m/s using a peristaltic pump. The absorbance of X-rays was measured after photoexcitation of the sample with a 400 nm laser with a 50 kHz repetition rate. The measurements were performed by following the pump-flow-probe method when pumped data was collected for 5 seconds followed by unpumped data collection for another 5 seconds by switching the laser on and off, respectively. For each X-ray energy, the data collection was repeated at least 3 times. Transient spectra at different 70–1140 µs time delays were recorded by changing the distance between spatially separated laser and X-ray probe beams while keeping jet velocity constant at 4.32 m/s. Regular X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectra were collected using the same setup. The data presented in the manuscript was processed using an open-source X-ray Larch tool.[3,4]

[1] - Osterrieth, J. W. M. et al. Advanced Materials 2022, 34 (27), 2201502. https://doi.org/10.1002/adma.202201502
[2] - Smolentsev, G. et al. Journal of Physical Chemistry C 2013, 117 (34), 17367–17375. https://doi.org/10.1021/jp4010554
[3] - Newville, M. Larch. J Phys Conf Ser 2013, 430 (1), 012007. https://doi.org/10.1088/1742-6596/430/1/012007
[4] - Larch — xraylarch 0.9.66 documentation. https://xraypy.github.io/xraylarch/

***Description of the data in this data set***
The raw TEM images of NH2-MIL-125(Ti) and Co@NH2-MIL-125(Ti) are uploaded in .tif format.

Two .aif files (AIF stands for Adsorption Information Format, [5,6]) contains N2 sorption data of two phototcatalysts NH2-MIL-125(Ti) and Co@NH2-MIL-125(Ti).

[5] - Evans J.D. et al. Langmuir 2021, 37, 14, 4222–4226. https://doi.org/10.1021/acs.langmuir.1c00122
[6] - https://adsorptioninformationformat.com 

Two .txt files (with prefix XRD_...) for two phototcatalysts contains raw PXRD data with two columns corresponding to the X and Y axis - 2theta, [°], and Intensity values, [a.u.], respectively.

The folder "XAS" contains raw data set consisting of .txt files of Co K-edge XANES spectrum of Co foil, transient (70-1140 usec) XAS experiments and EXAFS measurements for Co@NH2-MIL-125(Ti) sorted in the corresponding folders.

The columns of the data files from the "XAS" folder's are described below:
posX is the Energy of incident beam
ShutterPos is the position of laser shutter (open or closed)
SAI01-MEAN is the incident flux measured with first ionization chamber
TrueFluoChannel2 is deadtime-corrected counts of fluorescence detector
Ge_abs is the absorption coefficient Ge_abs=TrueFluoChannel2/SAI01-MEAN
DifferenceSpectrum1 is the difference between laser_on and laser_off absorption spectra.
DifferenceWithoutNorm is the difference between laser_on and laser_off before normalization to the incident flux.
Columns AverageDifferenceCounts and AverageDifferenceNormalized contain sum of differences (DifferenceWithoutNorm or DifferenceSpectrum1) but for previous energy point.