Vertical-aligned CdS/g-C3N4 heterojunction nanocone arrays have been fabricated on silicon(100) substrates by a plasma sputting reaction deposition and pulsed laser deposition, successively. The morphology and structure of the as-fabricated nanocone arrays were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and Raman spectroscopy, revealing a single-crystalline hexagonal g-C3N4 structure of the g-C3N4 nanocone arrays and a poly-crystalline hexagonal wurtzite-structure of the CdS shells. The optical properties of the CdS/g-C3N4 nanocone arrays were studied by steady-state and time-resolved photoluminence and optical absorption measurements, showing that the CdS/g-C3N4 heterojunction could efficiently promote the separation of the electron–hole pairs generated in the nanocone arrays, which indicates the attractive prospects of the CdS/g-C3N4 nanocone arrays in the field of photocatalysis.

Single-crystalline g-C3N4 nanocones (g-CNNCs) were successfully synthesized on nickel-covered silicon (100) substrates supported on a graphite frame using a novel plasma sputtering reaction deposition method. The g-CNNCs have the characteristic photoluminescence peak of g-C3N4 and the longitudinal resistivity belonging to a semiconductor, which results in them having many potential applications.

Single-crystalline silicon, g-C3N4, and diamond nanocone arrays were synthesized on nickel-covered silicon (100) substrates by a novel method of plasma sputtering reaction deposition. The experimental results show that the morphologies, structures, and composition of the as-grown nanocones strongly depend on the ratios of the inlet mixed gases. The silicon, g-C3N4, and diamond nanocone arrays could be grown at the CH4/(N2 + H2) ratios of about 1/20–1/10, 1/150–1/60, and 0, respectively. The analyses of the optical emission spectra from the discharged plasma indicate that the inlet methane controls the growth of the nanocones by suppressing the H+-sputtering effect to adjust the amounts of the silicon, carbon, and nitrogen atoms attaining the substrate, which determines the composition, structures, and crystallinity of the grown nanocones.

Vertically and neatly arranged crystalline graphitic C3N4 (g-C3N4) nanocone arrays were firstly synthesized on nickel-covered silicon (1 0 0) substrates supported on a graphite frame. Synthesis was accomplished using an abnormal glow discharge plasma sputtering reaction deposition method with a feed gas mixture of CH4, N2 and H2. The experimental results show that the morphologies, structures, composition and photoluminescence of the grown nanostructures strongly depend on the CH4/(N2 + H2) ratios (0–1/10). The hexagonal g-C3N4 nanocone arrays were well grown at a CH4/(N2 + H2) ratio of around 1/150 as a result of the hydrogen ion sputtering of the graphite frame to generate a lot of carbon atoms, the hydrogen ion etching on the growing graphite structures, and the reaction between the active nitrogen atoms and the sputtered carbon atoms. The g-C3N4 nanocone arrays have the characteristic photoluminescence-peak of g-C3N4 and very nice wettability to the polymer absorber layers. At the higher or lower CH4/(N2 + H2) ratios, the silicon or diamond nanocone arrays were grown respectively due to the ion-sputtering of the silicon substrate and the inhibition of CHn-radicals on the H+-sputtering of the graphite frame or the mismatch between the sputtered carbon atoms and the dissociated nitrogen atoms.

Using pulsed-laser deposition method, crystalline ZnSe nano-needles have been grown on catalyst-coated silicon (100) substrates. The crystalline ZnSe nano-needles with the middle diameters of about 20–80 nm, and the lengths ranging from 100 to 600 nm can be grown densely on 300–400 °C substrates. The as-grown ZnSe nano-needles were well crystalline and base-grown. They are potential electron-capturing materials in polymer/inorganic hybrid solar cells for their properties of good electron-conductance and high ratio surface area. Based on the ZnSe nano-needle cathode, a five-layer composite structure of polymer/inorganic hybrid solar cell has been designed and fabricated. The absorption spectra of the blend of regioregular poly(3-hexylthiophene-2,5-diyl) and phenyl-C61-butyric acid methyl ester (P3HT:PCBM), ZnSe nano-needles and the combination of P3HT:PCBM and ZnSe nano-needles were examined by ultraviolet–visible-infrared spectrophotometer, respectively. The absorption bands of the combination of P3HT:PCBM and ZnSe nano-needles fit well with the solar spectral distribution.Highlights► Crystalline ZnSe nano-needles grown by pulsed laser deposition. ► A five-layer polymer/inorganic hybrid solar cell based on ZnSe nano-needles cathode. ► ZnSe nano-needles improve light absorption. ► Employment of ZnSe nano-needles increase the open-circuit voltage and fill factor.

Vertically aligned carbon nitride nanocone (CNNC) arrays were prepared on Ni-covered (100) silicon wafers by an abnormal glow discharge plasma assisted chemical vapor deposition method. In order to control the growth of the CNNC arrays, the distance of the anode tip to the substrate surface was adjusted for it affected the contents and activities of the species in the plasmas leading to the CNNC growth. Based on the characterization of the as-grown thin films and the analysis of the growth environments, the effects of the experimental conditions on the growth of the CNNC arrays were studied and their growth mechanism was discussed. The tip−substrate distance strongly affects the CNNC growth. Under appropriate experimental conditions, the vertically-aligned and intact CNNC arrays with the β-C3N4 microstructure and the minimum tip curvature diameter of only 3–4 nm could be fabricated. This kind of CNNC arrays have many potential applications, such as tips for microscopes, electron-emitting units in field emission displays, electron-capture electrodes of solar cells etc.Highlights►Vertically aligned carbon nitride nanocone arrays were prepared. ►An abnormal glow discharge plasma assisted chemical vapor deposition method. ►Tip-substrate distance strongly affects the growth of carbon nitride nanocones. ►The growth mechanism of carbon nitride nanocones is discussed.

CdS nanoneedles have been grown on Ni-coated Si (100) substrates by pulsed laser deposition. Substrate temperature and Ni-catalyst layer thickness were found to have great effects on the density and morphology of the as-grown CdS nanoneedles. Crystalline CdS nanoneedles with middle diameter and length of about 40 nm to 100 nm and 400 nm to 1000 nm, respectively, could be obtained at 350°C to 450°C on Ni-coated silicon (100) substrates, and nanoneedles with good shapes were obtained at 400°C substrate temperature. From the cross-section morphologies, it was found that the CdS nanoneedles grew out of the base CdS crystallite layer with thickness of about 500 nm. Based on the experimental results, vapor–solid and vapor–liquid–solid growth modes describe the CdS nanoneedle growth.

Vertically aligned binary CN nanocone (CNNC) arrays were prepared by a direct-current abnormal glow discharge plasma-assisted reaction deposition method. CNNCs were grown on silicon wafers covered by Ni intermediate layers. The experiments were carried out in environments of methane and nitrogen mixtures, with a total pressure of 5 Torr and CH4/N2 pressure ratios of 1/50 to 1/10. As-grown short CNNCs can have tip diameter of curvature of only 2 nm to 3 nm and are mainly crystalline β-C3N4, while long CNNCs are mainly amorphous with inclusions of β-C3N4-coated Ni crystals. Based on characterization and analysis of the as-grown binary CN nanostructures, their growth mechanism is proposed and discussed.

Pulsed laser deposition has been utilized to synthesize impurity-doped ZnO thin films on silicon substrate. Large-sized-mismatched group-V elements (AV) including P, As, Sb and Bi were used as dopants. Hall effect measurements show that hole concentration in the order of 1016–1018 cm−3, resistivity in the range of 10–100 Ω cm, Hall mobility in the range of 10–100 cm2/Vs were obtained only for ZnO:As and ZnO:Bi thin films. X-ray diffraction measurements reveal that the films possess polycrystallinity or nanocrystallinity with ZnO (002) preferred orientation. Guided by X-ray photoemission spectroscopy analyses and theoretical calculations for large-sized-mismatched group-V dopant in ZnO, the AZnV–2VZn complexes are believed to be the most possible acceptors in the p-type AV-doped ZnO thin films.

The preparation of bismuth doped ZnSe films on silicon (1 0 0) by pulsed laser deposition (PLD) is reported. Bismuth was used as a p-type dopant source material for ZnSe. The stable p-type films with hole carrier concentration of about 1016–1018 cm−3 were obtained. By scanning electron microscopy (SEM) and X-ray diffraction (XRD), it was found that the ambient pressure during film deposition has much to do with the morphology and crystallinity of the as-deposited products. The presence of Bi in the Bi-doped ZnSe films was confirmed by the X-ray photoelectron spectroscopy (XPS) and the possibility of a BiZn–2VZn complex forming a shallow acceptor level was discussed.

Nanocrystalline zinc-blende-structured ZnSe:N films have been deposited on GaAs(100) substrates by pulsed laser deposition (PLD). The growth of the nanocrystalline ZnSe:N films is found to be greatly affected by the pressure of ambient N2. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) results show that the morphologies of the as-grown films are sensitive to the ambient pressure at a fixed substrate temperature of 300 °C, and the sizes of the as-grown ZnSe:N nanocrystals increase as the ambient pressure increases from 0.1 Pa to 100 Pa. The average sizes of the as-grown nanocrystals are estimated to be about 19 nm, 29 nm, and 71 nm for 0.1 Pa, 1 Pa, and 100 Pa ambient N2 pressure, respectively. X-ray photoelectron spectroscopy analyses show that the N-doping concentration in the as-grown film is over 1021 cm−3. Raman spectra demonstrate the broadening of the longitudinal optical (LO) phonon and transverse optical (TO) phonon modes of the ZnSe nanocrystals. Based on these analyses, the mechanism of the formation of ZnSe:N nanocrystals is discussed.

•The NiCx nanorods were synthesized via PLD accompanied by N2 annealing.•The NiCx nanorods were characterized by FESEM, TEM, HRTEM, SAED and FFT.•The effects of the experimental conditions on the growth of the NCNRs were analyzed.•The as-grown NiCx nanorod films can have excellent visible-light transmittance.Crystalline NiCx nanorods (NCNRs) were successfully prepared on fused silica and sapphire (0001) substrates with different shapes and growth orientations via the pulsed laser deposition accompanied by N2 annealing. The effects of experimental parameters including substrates, annealing duration, temperature and environment on the growth of crystalline NCNRs were studied in detail. Densely and uniformly distributed NCNRs with varied crystal orientations of hexagonal structure could be grown on silica and sapphire substrates, and only groups of SiO2 nanowires were grown on Si substrates. The NCNRs can be formed within only 3 min in pure N2 atmosphere at the annealing temperature of 1200 °C. It was found that the pure N2 atmosphere in the annealing process was necessary for the NCNR growth and the annealing in air could only obtain sparsely distributed nano-scaled particles. Besides, the NCNR films demonstrated excellent transmittance in visible light.

Vertical-aligned CdS/g-C3N4 heterojunction nanocone arrays have been fabricated on silicon(100) substrates by a plasma sputting reaction deposition and pulsed laser deposition, successively. The morphology and structure of the as-fabricated nanocone arrays were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and Raman spectroscopy, revealing a single-crystalline hexagonal g-C3N4 structure of the g-C3N4 nanocone arrays and a poly-crystalline hexagonal wurtzite-structure of the CdS shells. The optical properties of the CdS/g-C3N4 nanocone arrays were studied by steady-state and time-resolved photoluminence and optical absorption measurements, showing that the CdS/g-C3N4 heterojunction could efficiently promote the separation of the electron–hole pairs generated in the nanocone arrays, which indicates the attractive prospects of the CdS/g-C3N4 nanocone arrays in the field of photocatalysis.