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).
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Publication number: 20230311037Abstract: 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: ApplicationFiled: July 17, 2020Publication date: October 5, 2023Inventor: Wallace Woon Fong LEUNG
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Patent number: 11217751Abstract: 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: GrantFiled: April 2, 2015Date of Patent: January 4, 2022Assignee: THE HONG KONG POLYTECHNIC UNIVERSITYInventors: Wallace Woon-Fong Leung, Jingchuan Wang, Lijun Yang
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Patent number: 11148085Abstract: 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: GrantFiled: December 3, 2018Date of Patent: October 19, 2021Assignee: THE HONG KONG POLYTECHNIC UNIVERSITYInventor: Wallace Woon Fong Leung
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Publication number: 20190314746Abstract: 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: ApplicationFiled: December 3, 2018Publication date: October 17, 2019Inventor: Wallace Woon Fong LEUNG
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Patent number: 10434505Abstract: A photocatalyst includes a composite fiber having at least two crystalline semi-conductors that provide a heterojunction structure in the composite fiber.Type: GrantFiled: June 10, 2019Date of Patent: October 8, 2019Assignee: The Hong Kong Polytechnic UniversityInventors: Wallace Woon Fong Leung, Chun Pei
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Publication number: 20190291090Abstract: A photocatalyst includes a composite fiber having at least two crystalline semi-conductors that provide a heterojunction structure in the composite fiber.Type: ApplicationFiled: June 10, 2019Publication date: September 26, 2019Inventors: Wallace Woon Fong Leung, Chun Pei
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Patent number: 10315191Abstract: A photocatalyst includes a composite fiber having at least two crystalline semi-conductors that provide a heterojunction structure in the composite fiber.Type: GrantFiled: March 24, 2015Date of Patent: June 11, 2019Assignee: Hong Kong Polytechnic UniversityInventors: Wallace Woon Fong Leung, Chun Pei
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Patent number: 10071907Abstract: 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: GrantFiled: September 26, 2011Date of Patent: September 11, 2018Assignee: THE HONG KONG POLYTECHNIC UNIVERSITYInventors: Wallace Woon-fong Leung, Lijun Yang
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Patent number: 9754731Abstract: 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: GrantFiled: August 25, 2016Date of Patent: September 5, 2017Assignee: The Hong Kong Polytechnic UniversityInventors: Wallace Woon-fong Leung, Lijun Yang
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Publication number: 20170004928Abstract: 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: ApplicationFiled: August 25, 2016Publication date: January 5, 2017Inventors: Wallace Woon-fong Leung, Lijun Yang
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Patent number: 9455093Abstract: 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: GrantFiled: May 14, 2012Date of Patent: September 27, 2016Assignee: THE HONG KONG POLYTECHNIC UNIVERSITYInventors: Wallace Woon-fong Leung, Lijun Yang
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Patent number: 9311767Abstract: 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: GrantFiled: March 31, 2008Date of Patent: April 12, 2016Assignee: The Hong Kong Polytechnic UniversityInventors: Wallace Woon-Fong Leung, King-Lun Kwok, Mau-Wah Chan, So-Lam Sze
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Publication number: 20150287852Abstract: 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: ApplicationFiled: April 2, 2015Publication date: October 8, 2015Inventors: Wallace Woon-Fong LEUNG, Jingchuan WANG, Lijun YANG
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Publication number: 20150266013Abstract: A photocatalyst includes a composite fiber having at least two crystalline semi-conductors that provide a heterojunction structure in the composite fiber.Type: ApplicationFiled: March 24, 2015Publication date: September 24, 2015Inventors: Wallace Woon Fong Leung, Chun Pei
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Patent number: 9138669Abstract: 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: GrantFiled: August 2, 2013Date of Patent: September 22, 2015Assignee: AVALON NANOFIBER LIMITEDInventors: Wallace Woon-Fong Leung, Chi Ho Hung
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Patent number: 8987706Abstract: 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: GrantFiled: December 9, 2013Date of Patent: March 24, 2015Assignee: The Hong Kong Polytechnic UniversityInventors: Wallace Woon-Fong Leung, Lijun Yang
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Publication number: 20140158986Abstract: 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: ApplicationFiled: December 9, 2013Publication date: June 12, 2014Applicant: The Hong Kong Polytechnic UniversityInventors: Wallace Woon-Fong LEUNG, Lijun YANG
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Publication number: 20140044756Abstract: 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: ApplicationFiled: August 2, 2013Publication date: February 13, 2014Applicant: The Hong Kong Polytechnic UniversityInventors: Wallace Woon-Fong Leung, Chi Ho Hung
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Patent number: 8632243Abstract: 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: GrantFiled: March 10, 2008Date of Patent: January 21, 2014Assignee: The Hong Kong Polytechnic UniversityInventor: Wallace Woon-Fong Leung
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Publication number: 20130298981Abstract: 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: ApplicationFiled: May 14, 2012Publication date: November 14, 2013Inventors: Wallace Woon-fong Leung, Lijun Yang