A group of reductive 2D materials (R2D) with extended reactive vacancies and a method for making the R2D with extended reactive vacancies are provided, especially the example of the reductive boron nitride (RBN). To create defects such as vacancies, boron nitride (BN) powders are milled at cryogenic temperatures. Vacancies are produced by milling, and the vacancies can be used to reduce various metal nanostructures on RBN. Due to the thermal stability of the RBN and the enhanced catalytic performance of metal nanostructures, RBN-metals can be used for different catalysts, including electrochemical catalysts and high temperature catalysts.

Polymeric photovoltaic cell (or solar cell) with an inverted structure comprising: an anode; a first anode buffer layer; an active layer comprising at least one photoactive organic polymer as the electron donor and at least one organic electron acceptor compound; a cathode buffer layer; a cathode; wherein between said first anode buffer layer and said active layer a second anode buffer layer is placed comprising a hole transporting material, said hole transporting material being obtained through a process comprising: reacting at least one heteropoly acid containing at least one transition metal belonging to group 5 or 6 of the Periodic Table of the Elements; with at least an equivalent amount of a salt or a complex of a transition metal belonging to group 5 or 6 of the Periodic Table of the Elements with an organic anion, or with an organic ligand; in the presence of at least one organic solvent selected from alcohols, ketones, esters, preferably alcohols. Said polymer photovoltaic cell (or solar cell) with an inverted structure displays high photoelectric conversion efficiency values (η), i.e. a photoelectric conversion efficiency (η) greater than or equal to 4.5%, and good open circuit voltage (Voc), short-circuit current density (Jsc) and fill factor (FF) values. Furthermore, said polymer photovoltaic cell (or solar cell) with an inverted structure is able to maintain said values over time, in particular, in terms of photoelectric conversion efficiency (η).

Polymeric photovoltaic cell (or solar cell) with an inverted structure comprising: an anode; a first anode buffer layer; an active layer comprising at least one photoactive organic polymer as the electron donor and at least one organic electron acceptor compound; a cathode buffer layer; a cathode; wherein between said first anode buffer layer and said active layer a second anode buffer layer is placed comprising a hole transporting material, said hole transporting material being obtained through a process comprising: reacting at least one heteropoly acid containing at least one transition metal belonging to group 5 or 6 of the Periodic Table of the Elements; with at least an equivalent amount of a salt or a complex of a transition metal belonging to group 5 or 6 of the Periodic Table of the Elements with an organic anion, or with an organic ligand; in the presence of at least one organic solvent selected from alcohols, ketones, esters, preferably alcohols. Said polymer photovoltaic cell (or solar cell) with an inverted structure displays high photoelectric conversion efficiency values (η), i.e. a photoelectric conversion efficiency (η) greater than or equal to 4.5%, and good open circuit voltage (Voc), short-circuit current density (Jsc) and fill factor (FF) values. Furthermore, said polymer photovoltaic cell (or solar cell) with an inverted structure is able to maintain said values over time, in particular, in terms of photoelectric conversion efficiency (η).

A method for preparing an ordered cross-stacked metal oxide nanowire array is provided. The method includes the following steps: conducting synthesis by using an amphiphilic diblock copolymer as a structure directing agent, tetrahydrofuran (THF) as a solvent and polyoxometalates (POMs) as an inorganic precursor, where the diblock copolymer can interact with POMs via an electrostatic force to form a core-shell cylindrical micelle in the solvent, which self-assembles to form an ordered multilayer-crossed organic-inorganic composite nanostructure during an evaporation process; the template is removed by calcination in air, thereby obtaining ordered and crossed metal oxide nanowires with various elements doping. The nanowire array material has a high specific surface area, a high crystallinity, and realizes uniform doping of heteroatoms.

A method for preparing an ordered cross-stacked metal oxide nanowire array is provided. The method includes the following steps: conducting synthesis by using an amphiphilic diblock copolymer as a structure directing agent, tetrahydrofuran (THF) as a solvent and polyoxometalates (POMs) as an inorganic precursor, where the diblock copolymer can interact with POMs via an electrostatic force to form a core-shell cylindrical micelle in the solvent, which self-assembles to form an ordered multilayer-crossed organic-inorganic composite nanostructure during an evaporation process; the template is removed by calcination in air, thereby obtaining ordered and crossed metal oxide nanowires with various elements doping. The nanowire array material has a high specific surface area, a high crystallinity, and realizes uniform doping of heteroatoms.

Provided is a titanium oxide fine particle mixture having a high photocatalytic activity, especially a high photocatalytic activity in the visible light region. The titanium oxide fine particle mixture contains: first titanium oxide fine particles; and second titanium oxide fine particles, wherein the second titanium oxide fine particles are titanium oxide fine particles with at least an iron component and a silicon component solid-dissolved therein, and the first titanium oxide fine particles are titanium oxide fine particles that may have a component(s) other than an iron component and a silicon component solid-dissolved therein.

Provided is a fluorite-based material thin film including an orthorhombic crystal structure having a symmetric segment and a non-symmetric segment; and at least two domains having different polarization directions. At least one of, the symmetric segment is not present at a wall between the domains, or at least two symmetric segments are consecutive. Also provided is a semiconductor device including the fluorite-based material thin film having an orthorhombic crystal structure. A polarization direction of the fluorite-based material thin film is configured to be changed by a structural transition between the symmetric segment and the non-symmetric segment.

Provided is a fluorite-based material thin film including an orthorhombic crystal structure having a symmetric segment and a non-symmetric segment; and at least two domains having different polarization directions. At least one of, the symmetric segment is not present at a wall between the domains, or at least two symmetric segments are consecutive. Also provided is a semiconductor device including the fluorite-based material thin film having an orthorhombic crystal structure. A polarization direction of the fluorite-based material thin film is configured to be changed by a structural transition between the symmetric segment and the non-symmetric segment.

The present invention discloses a polymer-metal compound composite ink, a preparation method and application thereof. The composite ink comprises: at least one polymer; at least one metal compound material, the metal compound material being selected from polyoxometalate compounds and nanocrystalline metal oxides; at least one solvent which is used for forming a disperse system in the form of a uniform fluid together with the remaining components in the composite ink. The present invention also discloses a method for preparing the composite ink. The composite ink of the present invention is easily available in raw material, easy to prepare and low in cost, and can be manufactured into a composite thin film by spin-coating, printing or in other ways. The composite thin film, as an electrode modification layer, can be applied to photoelectric devices such as solar cells or light-emitting diodes, so as to improve the contact performance between an electrode and an organic active layer and thus enhance the performance and yield of photoelectric devices.

A production device, method and application of nano-sized zinc molybdate. The device includes a double-cone mixer; an elevator is obliquely provided at a bottom of a discharge port of the double-cone mixer; a rear end of the elevator is located above a feeder; the feeder is connected to one end of an electric heating converter, an other end of the electric heating converter is connected to a finished product bin; a top of the finished product bin is provided with an atomizing nozzle for adding nanomaterial dispersant; the atomizing nozzle is connected to a syringe pump by pipeline. High-purity nano-sized molybdenum trioxide and nano-sized zinc oxide are adopted to synthesize nano-sized zinc molybdate in an electric heating converter. The nano-sized zinc molybdate prepared by the device and method can be used for treatment of African swine fever virus, coronavirus, and AIDS phase I, Ebola, dengue fever, polio viruses.