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1. Addition of H 2 Across a Cobalt–Phosphorus Bond

   https://doi.org/10.1002/anie.201710100  

   Poitras, Andrew M. ; Knight, Sadie E. ; Bezpalko, Mark W. ; Foxman, Bruce M. ; Thomas, Christine M. ( January 2018 , Angewandte Chemie International Edition)

   Addition of H₂across the cobalt–phosphorus bond of (PPP)CoPMe₃(3) is demonstrated, where PPP is a monoanionic diphosphine pincer ligand with a central N‐heterocyclic phosphido (NHP⁻) donor. The chlorophosphine Co^IIcomplex (PP^ClP)CoCl₂(2) can be generated through coordination of the chlorophosphine ligand (PP^ClP,1) to CoCl₂. Subsequent reduction of2with KC₈in the presence of PMe₃generates (PPP)CoPMe₃(3), in which both the phosphorus and cobalt centers have been reduced. The addition of 1 atm of H₂to complex3cleanly affords (PP^HP)Co(H)PMe₃(4), in which H₂has ultimately been added across the metal–phosphorus bond. Complex4was characterized spectroscopically and using computational methods to predict its geometry.

    

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2. Addition of H 2 Across a Cobalt–Phosphorus Bond

   https://doi.org/10.1002/ange.201710100  

   Poitras, Andrew M. ; Knight, Sadie E. ; Bezpalko, Mark W. ; Foxman, Bruce M. ; Thomas, Christine M. ( January 2018 , Angewandte Chemie)

   Addition of H₂across the cobalt–phosphorus bond of (PPP)CoPMe₃(3) is demonstrated, where PPP is a monoanionic diphosphine pincer ligand with a central N‐heterocyclic phosphido (NHP⁻) donor. The chlorophosphine Co^IIcomplex (PP^ClP)CoCl₂(2) can be generated through coordination of the chlorophosphine ligand (PP^ClP,1) to CoCl₂. Subsequent reduction of2with KC₈in the presence of PMe₃generates (PPP)CoPMe₃(3), in which both the phosphorus and cobalt centers have been reduced. The addition of 1 atm of H₂to complex3cleanly affords (PP^HP)Co(H)PMe₃(4), in which H₂has ultimately been added across the metal–phosphorus bond. Complex4was characterized spectroscopically and using computational methods to predict its geometry.

    

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3. Gate‐Tunable Photoresponse Time in Black Phosphorus–MoS 2 Heterojunctions

   https://doi.org/10.1002/adom.201800832  

   Walmsley, Thayer S. ; Chamlagain, Bhim ; Rijal, Upendra ; Wang, Tianjiao ; Zhou, Zhixian ; Xu, Ya‐Qiong ( December 2018 , Advanced Optical Materials)

   Gate‐/wavelength‐dependent scanning photocurrent measurements of black phosphorous (BP)–MoS₂heterojunctions have shown that the Schottky barrier at the MoS₂–metal interface plays an important role in the photoresponse dynamics of the heterojunction. When the Fermi level is close to the conduction band of MoS₂, photoexcited carriers can tunnel through the narrow depletion region at the MoS₂–metal interface, leading to a short response time of 13 µs regardless of the incident laser wavelength. This response speed is comparable or better than that of other few‐layer BP–MoS₂heterojunctions. Conversely, when the MoS₂channel is in the off‐state, the resulting sizeable Schottky barrier and depletion width make it difficult for photoexcited carriers to overcome the barrier. This significantly delays the carrier transit time and thus the photoresponse speed, leading to a wavelength‐dependent response time since the photoexcited carriers induced by short wavelength photons have a higher probability to overcome the Schottky barrier at the MoS₂–metal interface than long wavelength photons. These studies not only shed light on the fundamental understanding of photoresponse dynamics in BP–MoS₂heterojunctions, but also open new avenues for engineering the interfaces between 2D materials and metal contacts to reduce the response time of 2D optoelectronics.

    

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4. Efficient hole transfer from monolayer WS 2 to ultrathin amorphous black phosphorus

   https://doi.org/10.1039/C8NH00234G  

   Bellus, Matthew Z. ; Yang, Zhibin ; Zereshki, Peymon ; Hao, Jianhua ; Lau, Shu Ping ; Zhao, Hui ( January 2019 , Nanoscale Horizons)

   The newly developed van der Waals materials allow fabrication of multilayer heterostructures. Early efforts have mostly focused on heterostructures formed by similar materials. More recently, however, attempts have been made to expand the types of materials, such as topological insulators and organic semiconductors. Here we introduce an amorphous semiconductor to the material library for constructing van der Waals heterostructures. Samples composed of 2 nm amorphous black phosphorus synthesized by pulsed laser deposition and monolayer WS 2 obtained by mechanical exfoliation were fabricated by dry transfer. Photoluminescence measurements revealed that photocarriers excited in WS 2 of the heterostructure transfer to amorphous black phosphorus, in the form of either energy or charge transfer, on a time scale shorter than the exciton lifetime in WS 2 . Transient absorption measurements further indicate that holes can efficiently transfer from WS 2 to amorphous black phosphorus. However, interlayer electron transfer in either direction was found to be absent. The lack of electron transfer from amorphous black phosphorus to WS 2 is attributed to the localized electronic states in the amorphous semiconductor. Furthermore, we show that a hexagonal BN bilayer can effectively change the hole transfer process. 

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5. Symmetric complementary logic inverter using integrated black phosphorus and MoS 2 transistors

   https://doi.org/10.1088/2053-1583/3/1/011006  

   Su, Yang ; Kshirsagar, Chaitanya U. ; Robbins, Matthew C. ; Haratipour, Nazila ; Koester, Steven J. ( February 2016 , 2D Materials)