O₁₄Pr₄W₄
rare earth oxide · rare earth ceramicO14Pr4W4 is a rare earth oxide suitable as rare earth ceramic. Color: neutral. Fired at 1200°C from 2 precursors (WO3, Pr6O11). Workshop batch: 100g at €42.24. Compressive strength ~100 MPa; estimated 0.90 kg CO₂/kg (+309% vs clay brick). Notable: uv luminescent, electrochromic tungstate. Confidence: medium.
- forms at
- 1200 °C · high-fire
- replaces
- clay brick
- CO₂
- 309% higher than clay brick (0.90 vs 0.22 kg CO₂/kg; 4.1× higher)
- energy
- 100% higher than clay brick (6.00 vs 3.00 MJ/kg; 2.0× higher)
- compressive
- 100 MPa
- density
- 8.19 g/cm³
- crystal
- tetragonal
- band gap
- 2.43 eV
- cost
- €422.40/kg · €42.24 / 100 g batch
- confidence
- medium (synthesis route)
- potential
- 0.37 · env 0.00 · novel 1.00 · struct 0.20 · lineage 0.50 · supply 0.10
- flags
- uv luminescent: Converts invisible ultraviolet into visible light. Signage panels, low-energy wayfinding tiles, emergency markings that draw their illumination from daylight rather than mains power. electrochromic tungstate: A voltage-switchable optical chemistry. In thin-film form a small DC signal shifts transmission from clear to tinted blue, opening the door to dimmable glazing and responsive partitions that do not need mechanical shading.
Architectural potential
A simpler rare-earth ceramic than its lithium-tellurium cousin, built on praseodymium-tungstate alone but reaching the same dual-function register: UV luminescence and voltage-switchable tinting. The density climbs to 8.19 g/cm³, the highest in this batch, which shifts the specification logic — at that density even a small tile reads as genuinely heavy, which gives the material a mineral register that the lithium-bearing version lacks. Natural placements are signage patches in civic architecture, accent cladding tiles in theatre foyers and concert-hall interiors, wayfinding pieces in hospital and metro corridors where the UV-driven glow replaces mains LEDs during low-light hours, and small façade inserts that tint on signal. Compression at 100 MPa keeps the material in the overlay register rather than the mass register; the three-hundred-per-cent CO₂ increase against clay brick means the piece is bought for behaviour, not for volume. Against the lithium-tellurium variant, the simpler chemistry reduces supply-chain risk on the tellurium side but concentrates it on the praseodymium, which remains the limiting element. The caveat is cost and rarity: €42.24 per 100 g batch, supply-chain score near zero, workshop maximum of 300 g, and untested in architectural production beyond the single tile. This is a material for one signature piece per project, not for any repeated cladding run.
Material character
The slab reads a neutral off-white with a soft green undertone from the praseodymium-tungstate matrix, warmer than a pure tungstate and cooler than the lithium-bearing variant in the same family. At 8.19 g/cm³ and 70×70×25 mm the tile refuses a casual one-hand lift — surprising density for its thin footprint, close to the hand-feel of a lead crystal or a dense tungsten alloy, and the thinnest slab in the batch by some margin. Surface is sintered matte with a fine closed grain and a slight yellow cast along the skin where praseodymium migrated during the sinter; edges cold-cut, carrying the usual diamond-saw kerf along the arris. Under 365 nm UV the face shifts to a saturated cool green, brighter and more even than the lithium-tellurium sibling.
Recipe
100 g batch · peak 1200 °C| element | precursor | formula | mass | safety |
|---|---|---|---|---|
| Pr | praseodymium oxide | Pr6O11 | 42.34 g | moderate |
| W | tungsten trioxide (yellow) | WO3 | 57.66 g | moderate |
- 1Ramp
- 2Hold
- 3Ramp
- 4Ramp
- 5Hold
- 6Ramp
- 7Ramp
UV-luminescent — emits visible light under 365 nm UV
Electrochromic — color switches under applied voltage (thin-film chemistry)