https://onlinelibrary.wiley.com/doi/epdf/10.1002/aenm.201903696

Highly Efficient Perovskite Solar Cells Enabled by Multiple Ligand Passivation

We synthesize the colloidal carbon/graphene quantum dots 1–9 nm in diameter and study their photoluminescence properties. Surprisingly, the luminescence properties of a fixed collection of colloidal carbon quantum dots can be systematically changed as the concentration varies. A model based on photon reabsorption is proposed which explains well the experiment. Infrared spectral study indicates that the surfaces of the carbon quantum dots are substantially terminated by oxygen atoms, which causes their ultra-high hydrophilicity. Our result clarifies the mystery of distinct emission colors in carbon quantum dots and indicates that photon reabsorption can strongly affect the luminescence properties of colloidal nanocrystals.

Red shift in the photoluminescence of colloidal carbon quantum dots induced by photon reabsorption

Plasma polymers of acrylic (propenoic) acid and propanoic acid were prepared from inductively coupled, radio-frequency-induced plasmas excited in vapors of the starting materials. The plasma polymers were characterized by X-ray photoelectron spectroscopy (XPS), infrared reflection absorption spectroscopy (IRAS), and static secondary-ion mass spectrometry (SIMS). Detailed interpretation of the spectra allows determination of the distribution of chemical functionalites at the surface of the product and of the influence of unsaturation and plasma power on this distribution. The results are discussed in the context of previously proposed mechanisms of plasma polymerization of the compounds under investigation.

Characterization of plasma polymers of acrylic acid and propanoic acid

Highly efficient flame retardant, flexible, and strong adhesive intumescent coating on polypropylene using hyperbranched polyamide

http://absimage.aps.org/image/MAR16/MWS_MAR16-2015-000147.pdf

Spectra analysis of the XPS core and valence energy levels of polymers by an ab initio mo method using simple model molecules

The HAM/3 method was used to provide a better assignment of the valence X-ray photoelectron spectra of 16 polymers involving nitrogen, oxygen, fluorine, a glucose unit, and a benzene nucleus using the monomer, dimer or trimer model molecules without consideration of the contraction factor of the energy scale. The calculated Al Kα photoelectron spectra were obtained using Gaussian functions of a fixed approximate linewidth, 0.10 Ik and Ik = I′k − WD, where I′k is the vertical ionization potential of each MO and WD is an approximate shift to account for the work function of the sample and other energy (polarization energy and so on) effects. We assumed that WD corresponds to the shift that we must apply before we can compare the calculated spectrum for the single model molecule with the observed spectrum for the solid. The approximate linewidth corresponds to the experimental result that the inner valence spectra are broader. The theoretical spectra showed good agreement with the spectra of the polymers obs...

Simulation of the Valence X-Ray Photoelectron Spectra of 16 Polymers by the Semiempirical HAM/3 MO Method Using the Model Molecules

Spectral Analysis of Polystyrene, Polypropylene, and Poly(methyl methacrylate) Polymers in TOF SIMS and XPS by MO Calculations Using the Model Oligomers

/pdf/spectral-analysis-of-polystyrene-polypropylene-and-poly-speczfh634.pdf

The valence X-ray photoelectron spectra of ten polymers [(–CH2–CHR–)n (R = C6H5, OCH3, COCH3, COOH, COOCH3, OCOCH3, CONH2, C4H6NO (N-vinylpyrrolidone)) and (–CH2–C(CH3)R–)n (R = COOCH3 and CONH2)] were analyzed by a semi-empirical HAM/3 MO method using trimer model molecules [H–(–CH2–CHR–)3–H (R = C6H5, OCH3, COCH3, COOH, COOCH3, OCOCH3, CONH2, and C4H6NO (N-vinylpyrrolidone) and H–(–CH2–C(CH3)R–)3–H (R = COOCH3 and CONH2)], respectively. The calculated Al Kα photoelectron spectra were obtained using Gaussian functions of a fixed approximate linewidth (0.10 Ik; Ik = I′k − ΔW, where I′k is the vertical ionization potential of each MO and ΔW is an approximate shift to account for the work-function effects. We assumed that ΔW corresponds to the shift that we must apply before we could compare the calculated spectrum for a single model molecule with the observed spectrum for the solid. The theoretical spectra showed good agreement with the spectra of the polymers, as observed between 0—40 eV.

Analysis of the Valence X-Ray Photoelectron Spectra of Eight (-CH2-CHR-)n and Two (-CH2-C(CH3)R-)n Polymers by the Semi-Empirical HAM/3 MO Method Using the Trimer Model Molecules H-(-CH2-CHR-)3-H and H-(-CH2-C(CH3)R-)3-H.

Naoya Kobayashi

Papers

Spectra analysis of the XPS core and valence energy levels of polymers by an ab initio mo method using simple model molecules

Simulation of the Valence X-Ray Photoelectron Spectra of 16 Polymers by the Semiempirical HAM/3 MO Method Using the Model Molecules

Spectral Analysis of Polystyrene, Polypropylene, and Poly(methyl methacrylate) Polymers in TOF SIMS and XPS by MO Calculations Using the Model Oligomers

Analysis of the Valence X-Ray Photoelectron Spectra of Eight (-CH2-CHR-)n and Two (-CH2-C(CH3)R-)n Polymers by the Semi-Empirical HAM/3 MO Method Using the Trimer Model Molecules H-(-CH2-CHR-)3-H and H-(-CH2-C(CH3)R-)3-H.

Spectra analysis of XPS valence energy levels of polymers by the semi-empirical MO method—I. Polyvinylalcohol, polyethyleneoxide and polyvinylchloride