Patents by Inventor Woon-Fong Leung

Woon-Fong Leung has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20230311037
    Abstract: A high filtration filter for filtering aerosols with low pressure drop across the filter and reduced cake formation when the aerosols penetrate through from an upstream side to a downstream side is disclosed. The filter (100) includes a plurality of module layers (110) and a plurality of separators (120). An individual module layer is an electrostatically-charged polyvinylidene fluoride (PVDF) nanofiber mat. The electrostatically-charged PVDF nanofiber mat with charged nanofibers is configured to better capture aerosols. The plurality of module layers and the plurality of separators are alternatingly stacked and connected to one another. Each of the individual module layers has an appropriate fiber basis weight, thereby the aerosols are captured by the charged nanofibers and distributed uniformly across an entire width of the filter from the upstream side (41) to the downstream side (42).
    Type: Application
    Filed: July 17, 2020
    Publication date: October 5, 2023
    Inventor: Wallace Woon Fong LEUNG
  • Patent number: 11217751
    Abstract: PbI2 thin film crystallization control is prerequisite of high-quality perovskite layer for the sequentially solution-processed perovskite solar cells. According to the present invention, an efficient-and-simple method has been developed by adding halogen acid additive to improve perovskite thin-film quality and an efficiency of at least 15.2% is obtained. This approach improves coverage, uniformity and stability of pervoskite thin-film. In addition, a nanofiber scaffold is incorporated into the perovskite layer so as to reduce the amount of grain boundaries, thus substantially reducing electron recombination within these boundaries.
    Type: Grant
    Filed: April 2, 2015
    Date of Patent: January 4, 2022
    Assignee: THE HONG KONG POLYTECHNIC UNIVERSITY
    Inventors: Wallace Woon-Fong Leung, Jingchuan Wang, Lijun Yang
  • Patent number: 11148085
    Abstract: A charged multilayer nanofiber filter for air filtration and the fabrication method thereof is disclosed. The charged multilayer nanofiber filter has a plurality of charged nanofiber mats. Each of the plurality of charged nanofiber mats is obtained by charging nanofiber mats individually before assembling. The nanofiber mat comprises a nanofiber layer and a substrate layer. The plurality of charged nanofiber mats is assembled such that the nanofiber layers and the substrate layers are stacked together in an alternative manner. The charged multilayer nanofiber filter can be fabricated by electrospinning a polymer solution on the substrate layer to obtain a nanofiber mat, charging the nanofiber mat to obtain a charged nanofiber mat, and assembling a plurality of charged nanofiber mats to form the charged multilayer nanofiber filter.
    Type: Grant
    Filed: December 3, 2018
    Date of Patent: October 19, 2021
    Assignee: THE HONG KONG POLYTECHNIC UNIVERSITY
    Inventor: Wallace Woon Fong Leung
  • Publication number: 20190314746
    Abstract: A charged multilayer nanofiber filter for air filtration and the fabrication method thereof is disclosed. The charged multilayer nanofiber filter has a plurality of charged nanofiber mats. Each of the plurality of charged nanofiber mats is obtained by charging nanofiber mats individually before assembling. The nanofiber mat comprises a nanofiber layer and a substrate layer. The plurality of charged nanofiber mats is assembled such that the nanofiber layers and the substrate layers are stacked together in an alternative manner. The charged multilayer nanofiber filter can be fabricated by electrospinning a polymer solution on the substrate layer to obtain a nanofiber mat, charging the nanofiber mat to obtain a charged nanofiber mat, and assembling a plurality of charged nanofiber mats to form the charged multilayer nanofiber filter.
    Type: Application
    Filed: December 3, 2018
    Publication date: October 17, 2019
    Inventor: Wallace Woon Fong LEUNG
  • Patent number: 10434505
    Abstract: A photocatalyst includes a composite fiber having at least two crystalline semi-conductors that provide a heterojunction structure in the composite fiber.
    Type: Grant
    Filed: June 10, 2019
    Date of Patent: October 8, 2019
    Assignee: The Hong Kong Polytechnic University
    Inventors: Wallace Woon Fong Leung, Chun Pei
  • Publication number: 20190291090
    Abstract: A photocatalyst includes a composite fiber having at least two crystalline semi-conductors that provide a heterojunction structure in the composite fiber.
    Type: Application
    Filed: June 10, 2019
    Publication date: September 26, 2019
    Inventors: Wallace Woon Fong Leung, Chun Pei
  • Patent number: 10315191
    Abstract: A photocatalyst includes a composite fiber having at least two crystalline semi-conductors that provide a heterojunction structure in the composite fiber.
    Type: Grant
    Filed: March 24, 2015
    Date of Patent: June 11, 2019
    Assignee: Hong Kong Polytechnic University
    Inventors: Wallace Woon Fong Leung, Chun Pei
  • Patent number: 10071907
    Abstract: A photovoltaic cell comprises a first electrode that includes a first transparent conductive substrate, a first layer having a plurality of first semiconductor nanofibers, and a second layer having a plurality of second semiconductor super-fine fibers, the first semiconductor nanofibers having an average diameter smaller than an average diameter of the second semiconductor super-fine fibers, a light absorbing material adsorbed to at least some of the first semiconductor nanofibers and second semiconductor super-fine fibers, a second electrode includes a second transparent conductive substrate, and electrolytes dispersed in the first and second layers.
    Type: Grant
    Filed: September 26, 2011
    Date of Patent: September 11, 2018
    Assignee: THE HONG KONG POLYTECHNIC UNIVERSITY
    Inventors: Wallace Woon-fong Leung, Lijun Yang
  • Patent number: 9754731
    Abstract: A method of producing an electrode of a dye-sensitized solar cell includes dispersing semiconductor nanoparticles on a transparent electrically conductive substrate, dispersing semiconductor nanofibers on the semiconductor nanoparticle layer, adsorbing onto all sides of the semiconductor nanofibers a first light absorption material, thereby sensitizing the semiconductor nanofibers, wherein the light absorption material has a first light absorption bandwidth, and depositing a second light absorption material in contact with and forming respective shells on the respective semiconductor nanofibers on which the first light absorption material is adsorbed, wherein the second light absorption material has a second light absorption bandwidth complementary to the first light absorption bandwidth.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: September 5, 2017
    Assignee: The Hong Kong Polytechnic University
    Inventors: Wallace Woon-fong Leung, Lijun Yang
  • Publication number: 20170004928
    Abstract: A dye-sensitized solar cell that includes an electrode having a semiconductor nanoparticle layer dispersed on a transparent conductive substrate, a plurality of semiconductor nanofibers dispersed on the nanoparticle layer, a first light absorption material is attached to the plurality of semiconductor nanofibers in which the first light absorption material having a first light absorption bandwidth, and a second light absorption material deposited on the light absorption material of the plurality of semiconductor nanofibers, the second light absorption material having a second light absorption bandwidth complementary to the first light absorption bandwidth, a counter electrode includes a metal-coated transparent conductive substrate, and an electrolyte in contact with the near-infrared light absorption material and the counter electrode.
    Type: Application
    Filed: August 25, 2016
    Publication date: January 5, 2017
    Inventors: Wallace Woon-fong Leung, Lijun Yang
  • Patent number: 9455093
    Abstract: A dye-sensitized solar cell that includes an electrode having a semiconductor nanoparticle layer dispersed on a transparent conductive substrate, a plurality of semiconductor nanofibers dispersed on the nanoparticle layer, a first light absorption material is attached to the plurality of semiconductor nanofibers in which the first light absorption material having a first light absorption bandwidth, and a second light absorption material deposited on the light absorption material of the plurality of semiconductor nanofibers, the second light absorption material having a second light absorption bandwidth complementary to the first light absorption bandwidth, a counter electrode includes a metal-coated transparent conductive substrate, and an electrolyte in contact with the near-infrared light absorption material and the counter electrode.
    Type: Grant
    Filed: May 14, 2012
    Date of Patent: September 27, 2016
    Assignee: THE HONG KONG POLYTECHNIC UNIVERSITY
    Inventors: Wallace Woon-fong Leung, Lijun Yang
  • Patent number: 9311767
    Abstract: The present invention relates to a system for product storage and methods of categorizing, storing, and delivering products to end users via the system, the system's components including a processor, a “smart shelving” device, boxes for insertion into and utilization by the “smart shelving” device, and ID readers. Through the present invention, products are able to be securely and more certainly delivered to the proper recipient of the products.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: April 12, 2016
    Assignee: The Hong Kong Polytechnic University
    Inventors: Wallace Woon-Fong Leung, King-Lun Kwok, Mau-Wah Chan, So-Lam Sze
  • Publication number: 20150287852
    Abstract: PbI2 thin film crystallization control is prerequisite of high-quality perovskite layer for the sequentially solution-processed perovskite solar cells. According to the present invention, an efficient-and-simple method has been developed by adding halogen acid additive to improve perovskite thin-film quality and an efficiency of at least 15.2% is obtained. This approach improves coverage, uniformity and stability of pervoskite thin-film. In addition, a nanofiber scaffold is incorporated into the perovskite layer so as to reduce the amount of grain boundaries, thus substaintially reducing electron recombination within these boundaries.
    Type: Application
    Filed: April 2, 2015
    Publication date: October 8, 2015
    Inventors: Wallace Woon-Fong LEUNG, Jingchuan WANG, Lijun YANG
  • Publication number: 20150266013
    Abstract: A photocatalyst includes a composite fiber having at least two crystalline semi-conductors that provide a heterojunction structure in the composite fiber.
    Type: Application
    Filed: March 24, 2015
    Publication date: September 24, 2015
    Inventors: Wallace Woon Fong Leung, Chun Pei
  • Patent number: 9138669
    Abstract: A method of making a multilayer filter and the multilayer filter made by the method. The method includes generally two steps. The first step is to coat a layer of nanofibers on a single side or both sides of a substrate medium to obtain a composite filter medium, and the second step is to fold the composite filter medium in a serpentine fashion to form a multilayer filter. The second step may alternatively be accomplished by stacking up a number of sheets of the composite filter medium to form a multilayer filter having a structure of two layers of nanofibers being sandwiched between two layers of said substrate medium. The resulting multilayer filter produced by either method contains at least one structural unit which has two layers of nanofibers being sandwiched between two layers of the substrate medium.
    Type: Grant
    Filed: August 2, 2013
    Date of Patent: September 22, 2015
    Assignee: AVALON NANOFIBER LIMITED
    Inventors: Wallace Woon-Fong Leung, Chi Ho Hung
  • Patent number: 8987706
    Abstract: The presently claimed invention provides a highly conductive composite used for electric charge transport, and a method for fabricating said composite. The composite comprises a plurality of one-dimensional semiconductor nanocomposites and highly conductive nanostructures, and the highly conductive nanostructures are incorporated into each of the one-dimensional semiconductor nanocomposite. The composite is able to provide fast electric charge transport, and reduce the rate of electron-hole recombination, ultimately increasing the power conversion efficiency for use in solar cell; provide fast electrons transport, storage of electrons and large surface area for adsorption and reaction sites of active molecular species taking part in photocatalytic reaction; enhance the sensitivity of a surface for biological and chemical sensing purposes for use in biological and chemical sensors; and lower the impedance and increase the charge storage capacity of a lithium-ion battery.
    Type: Grant
    Filed: December 9, 2013
    Date of Patent: March 24, 2015
    Assignee: The Hong Kong Polytechnic University
    Inventors: Wallace Woon-Fong Leung, Lijun Yang
  • Publication number: 20140158986
    Abstract: The presently claimed invention provides a highly conductive composite used for electric charge transport, and a method for fabricating said composite. The composite comprises a plurality of one-dimensional semiconductor nanocomposites and highly conductive nanostructures, and the highly conductive nanostructures are incorporated into each of the one-dimensional semiconductor nanocomposite. The composite is able to provide fast electric charge transport, and reduce the rate of electron-hole recombination, ultimately increasing the power conversion efficiency for use in solar cell; provide fast electrons transport, storage of electrons and large surface area for adsorption and reaction sites of active molecular species taking part in photocatalytic reaction; enhance the sensitivity of a surface for biological and chemical sensing purposes for use in biological and chemical sensors; and lower the impedance and increase the charge storage capacity of a lithium-ion battery.
    Type: Application
    Filed: December 9, 2013
    Publication date: June 12, 2014
    Applicant: The Hong Kong Polytechnic University
    Inventors: Wallace Woon-Fong LEUNG, Lijun YANG
  • Publication number: 20140044756
    Abstract: A method of making a multilayer filter and the multilayer filter made by the method. The method includes generally two steps. The first step is to coat a layer of nanofibers on a single side or both sides of a substrate medium to obtain a composite filter medium, and the second step is to fold the composite filter medium in a serpentine fashion to form a multilayer filter. The second step may alternatively be accomplished by stacking up a number of sheets of the composite filter medium to form a multilayer filter having a structure of two layers of nanofibers being sandwiched between two layers of said substrate medium. The resulting multilayer filter produced by either method contains at least one structural unit which has two layers of nanofibers being sandwiched between two layers of the substrate medium.
    Type: Application
    Filed: August 2, 2013
    Publication date: February 13, 2014
    Applicant: The Hong Kong Polytechnic University
    Inventors: Wallace Woon-Fong Leung, Chi Ho Hung
  • Patent number: 8632243
    Abstract: The present invention relates to a method for microfluidic mixing in a “lab-on-a-chip” environment. The methodology focuses on constant acceleration and deceleration about a mean angular speed with a rotating disk serving as the mixing platform. The methodology results in good mixing between different fluids.
    Type: Grant
    Filed: March 10, 2008
    Date of Patent: January 21, 2014
    Assignee: The Hong Kong Polytechnic University
    Inventor: Wallace Woon-Fong Leung
  • Publication number: 20130298981
    Abstract: A dye-sensitized solar cell that includes an electrode having a semiconductor nanoparticle layer dispersed on a transparent conductive substrate, a plurality of semiconductor nanofibers dispersed on the nanoparticle layer, a first light absorption material is attached to the plurality of semiconductor nanofibers in which the first light absorption material having a first light absorption bandwidth, and a second light absorption material deposited on the light absorption material of the plurality of semiconductor nanofibers, the second light absorption material having a second light absorption bandwidth complementary to the first light absorption bandwidth, a counter electrode includes a metal-coated transparent conductive substrate, and an electrolyte in contact with the near-infrared light absorption material and the counter electrode.
    Type: Application
    Filed: May 14, 2012
    Publication date: November 14, 2013
    Inventors: Wallace Woon-fong Leung, Lijun Yang