Nyakuchena J., Ostresh S., Neu J. et al. · Journal of Physical Chemistry Letters · 2023 · 5960-5965
Open a family to keep every result attached to its sample, method and conditions.
Paraphrased for this database from the authors’ stated interpretations — never quoted verbatim — and kept separate from reported measurements.
Photoconductive M-THQ MOFs can be used as photocathodes; Fe-THQ shows the highest photocurrent under light illumination.
Caveat: The LSV electrode is a composite MOF/Nafion/FTO photocathode; no normalised photocurrent density is text-reported.
14 · Summary · Figure 5 · Linked to 3 structured results
Fe-THQ is susceptible to oxidation in air, decreasing THz attenuation/photoconductivity and converting Fe(II) toward Fe(III) over time.
Caveat: Long-term air exposure is compared qualitatively; exact storage durations vary between two weeks in N2 and months in air.
12 · Fe-THQ oxidation · Figures S8 and S9 · Linked to 3 structured results
The M-THQ band gap follows Fe-THQ < Cu-THQ < Ni-THQ < Zn-THQ and is tuned by the metal node.
Caveat: Band gaps are extracted from diffuse reflectance/Tauc analysis of powders.
13 · Discussion · Figure 2 · Linked to 4 structured results
Metal node identity controls structural preference: Cu-THQ adopts a 2D square-planar/hexagonal structure, whereas Fe-, Ni-, and Zn-THQ adopt 3D structures.
Caveat: 3D assignments rely on comparison/refinement to previously reported models rather than new single-crystal structures.
5 · Results and discussion · Figure 1 · Linked to 2 structured results
Fe-THQ has the highest photoconduction in the series, with 6.1 S/m after 3.5 ps and 7.7 S/m after 2 ps pump delay, far above the previously reported Cu-THQ value.
Caveat: Authors note the time-resolved THz spectra do not closely resemble Drude-Smith behaviour and attribute this to low signal-to-noise ratio.
11 · OPTP spectroscopy · Figure 4 · Linked to 3 structured results
OTA and XTA support a long-lived ligand-to-metal charge-transfer state in Fe-THQ, persisting on nanosecond time scales and linked to photoconductivity.
Caveat: The main text reports >20 ns for Fe-THQ in the summary, while Table S3 gives a fitted 33.9 ns component; both indicate long-lived behaviour.
10 · XTA spectroscopy · Figure 3 and Figure S7 · Linked to 4 structured results
The photoconductivity and photocurrent performance trend is Fe-THQ > Cu-THQ > Ni-THQ > Zn-THQ.
Caveat: Cu photoconductivity value used for quantitative comparison is from a previous report; LSV currents are mainly qualitative or figure-read here.
13 · Discussion · Figures 4 and 5 · Linked to 4 structured results
Names and aliases are kept exactly within the paper’s own identity model.
| Material | Composition | Structure context | Source |
|---|---|---|---|
| Cu-THQ MOFBrowse family: Cu₃(C₆O₆)₂ (Cu–THQ / Cu–HHB) | Cu-THQCu · tetra-hydroxybenzoquinone (THQ) | 2D · Pristine2D hexagonal/Kagome-type honeycomb structure from square planar Cu coordination. | 5 · Results and discussion · Figure 1 |
| Fe-THQ MOF | Fe-THQFe · tetra-hydroxybenzoquinone (THQ) | 3D · Pristine3D cubic M-THQ conformation; isostructural with Ni- and Zn-THQ; mixed Fe(II)/Fe(III) valency discussed. | 5 · Results and discussion · Figure 1 |
| M-THQ MOF series | M-THQ, M = Fe, Cu, Ni, Zn; THQ = tetra-hydroxybenzoquinoneFe, Cu, Ni, Zn · tetra-hydroxybenzoquinone (THQ) | unknown · PristineComparative series containing 3D Fe-, Ni-, Zn-THQ and 2D Cu-THQ frameworks. | 2 · Abstract |
| Ni-THQ MOF | Ni-THQNi · tetra-hydroxybenzoquinone (THQ) | 3D · Pristine3D cubic M-THQ conformation; Ni synthesis required NMP cosolvent for improved crystallinity. | 5 · Results and discussion · Figure 1 |
| Zn-THQ MOF | Zn-THQZn · tetra-hydroxybenzoquinone (THQ) | 3D · Pristine3D cubic M-THQ conformation; closed shell Zn(II) gives largest reported band gap in the series. | 5 · Results and discussion · Figure 1 |
Sample form, processing state and composition status define the context for measurements.
| Sample | Form and role | Processing and geometry | Source |
|---|---|---|---|
| Cu-THQ powderresearch_0289__mat__mat_cu_thq | Powder · Target Sample · Pristine Framework | Washed and dried Cu-THQ product. | 2 · MOF synthesis |
| Fe-THQ film on glassresearch_0289__mat__mat_fe_thq | Thin Film · Target Sample · Pristine Framework | Film sample translated during OTA to avoid degradation.glass | 4 · Optical Transient Absorption (OTA) Spectroscopy |
| Fe-THQ flowing sample streamresearch_0289__mat__mat_fe_thq | Unknown · Target Sample · Pristine Framework | Flowing sample stream for XTA.550 um stream diameter | 4 · X-ray Transient Absorption (XTA) Spectroscopy |
| Fe-THQ powderresearch_0289__mat__mat_fe_thq | Powder · Target Sample · Pristine Framework | Washed and dried Fe-THQ product. | 3 · MOF synthesis |
| M-THQ-FTO photocathode seriesresearch_0289__mat__mat_mthq_series | Electrode · Paper Level Unspecified · Composite | MOF/Nafion ink drop-cast and air-dried on FTO for LSV.FTO slide | 4 · Linear sweep voltametry (LSV) |
| M-THQ mylar tape cell seriesresearch_0289__mat__mat_mthq_series | Powder · Paper Level Unspecified · Pristine Framework | Powder packed into punched mylar spacer for OPTP measurements.3 um mylar spacer sandwiched between THz-transparent tape · 3 um mylar spacer | 4 · Figure S3 · Figure S3 |
| M-THQ powder seriesresearch_0289__mat__mat_mthq_series | Powder · Paper Level Unspecified · Pristine Framework | Pristine Fe-, Cu-, Ni-, and Zn-THQ powders used for comparative structural and diffuse-reflectance measurements. | 5 · Results and discussion · Figure 1 |
| Ni-THQ film on glassresearch_0289__mat__mat_ni_thq | Thin Film · Target Sample · Pristine Framework | Film sample translated during OTA to avoid degradation.glass | 4 · Optical Transient Absorption (OTA) Spectroscopy |
| Ni-THQ flowing sample streamresearch_0289__mat__mat_ni_thq | Unknown · Target Sample · Pristine Framework | Flowing sample stream for XTA.550 um stream diameter | 4 · X-ray Transient Absorption (XTA) Spectroscopy |
| Ni-THQ powderresearch_0289__mat__mat_ni_thq | Powder · Target Sample · Pristine Framework | Dark grey solid from NMP/water pressure-tube synthesis. | 3 · MOF synthesis |
| Zn-THQ powderresearch_0289__mat__mat_zn_thq | Powder · Target Sample · Pristine Framework | Washed and dried Zn-THQ product. | 2 · MOF synthesis |