Black Phosphorus flakes
This BPs product differs from our other 0.5 gram and 1.0 gram highly crystalline BPs in the following regards: Typically, BPs crystals appear in needle-like layered form. BPs crystal in this product have big sheet like appearance much similar to graphite and MoS2. These crystals are growth at much higher pressures in comparison to other BPs crystals on our website, they are much harder to synthesize in sheet like form, and has less weight. These crystals measure ~1cm in size as shown in the product images.
Black phosphorus is an infrared (IR) semiconductor with a band gap of 0.3 eV in bulk which becomes ~1 eV when isolated down to monolayer (phosphorene). Our crystals are grown using special techniques (see below) in order to attain high crystalline anisotropy, minimal crystal defect density in the range of a record 3E9 - 1E10 cm-2 values, and high electronic / optical anisotropy. Thus, our crystals come ready for exfoliation with guaranteed crystalline, optical, and electronic anisotropy. Crystals are packaged under argon and is tightly seal to retain intrinsic properties of BPs crystals.
Growth technique matters: Conventional BPs growth typically involves chemical assisting agents such as Au, Sn, SnI4, and others to synthesize BPs crystals at low temperatures and low pressures. This process creates highly defected, low electronic mobility, and crystalline anisotropy crystals. Our company is dedicated to bringing electronic, optical, and scientific grade crystals. We synthesize our crystals at pressures as high as 3.4GPa to stabilize black phosphorus crystals without using any chemical assists (transport agents). Crystallization occurs over two (2) months period to ensure growth is slow enough to create defect free crystals. Yet, we still bring large quantities of BPs crystals at affordable rates. Note one order may contain more than one single crystal.
The properties of Black phosphorus crystals
XRD data collected from Black phosphorus crystals
Raman spectrum collected from Black phosphorus crystals
Confirmed Raman anisotropy in BPs crystals
Measured band gap from BPs crystals (note absence of below gap peaks - no localized excitons or absorption)
SEM images collected from black phosphorus crystals
EDS spectrum collected from BPs exfoliated onto Si substrates
SIMS purity information on BPs crystals
Partial List of Published Articles Using this Product
P. Zereshki et.al. Photocarrier dynamics in monolayer phosphorene and bulk black phosphorus; Nanoscale, 10, 11307-11313 (2018)
J.V Riffle "Impact of vacancies on electronic properties of black phosphorus probed by STM featured" Journal of Applied Physics 123, 044301 (2018)
Anisotropic Particle-Hole Excitations in Black Phosphorus, R. Schuster, J. Trinckauf, C. Habenicht, M. Knupfer, and B. Büchner. Phys. Rev. Lett. 115, 026404 – Published 10 July 2015
J,.He et.al ."Exceptional and Anisotropic Transport Properties of Photocarriers in Black Phosphorus" ACS Nano 10.1021/acsnano.5b02104 (2015_
R. Schuster et.al. "Anisotropic Particle-Hole Excitations in Black Phosphorus" Phys. Rev. Lett. 115, 026404 – Published 10 July 2015
M. Baibarac et.al ."Polarized Raman spectra of phosphorene in edge and top view measuring configurations" RSC Advances., 2016,6, 58003-58009
R. Schuster et.al. "Non-Generic Dispersion of Excitons in the Bulk of WSe2" Phys. Rev. B.94.085201 (2016)