Anung Riapanitra

Bio: Anung Riapanitra is an academic researcher from Jenderal Soedirman University. The author has contributed to research in topics: Coprecipitation & Photocatalysis. The author has an hindex of 5, co-authored 12 publications receiving 54 citations. Previous affiliations of Anung Riapanitra include Tohoku University.

Prospects and Challenges of MXenes as Emerging Sensing Materials for Flexible and Wearable Breath-Based Biomarker Diagnosis.

Abstract: A fully integrated, flexible, and functional sensing device for exhaled breath analysis drastically transforms conventional medical diagnosis to non-invasive, low-cost, real-time, and personalized health care. 2D materials based on MXenes offer multiple advantages for accurately detecting various breath biomarkers compared to conventional semiconducting oxides. High surface sensitivity, large surface-to-weight ratio, room temperature detection, and easy-to-assemble structures are vital parameters for such sensing devices in which MXenes have demonstrated all these properties both experimentally and theoretically. So far, MXenes-based flexible sensor is successfully fabricated at a lab-scale and is predicted to be translated into clinical practice within the next few years. This review presents a potential application of MXenes as emerging materials for flexible and wearable sensor devices. The biomarkers from exhaled breath are described first, with emphasis on metabolic processes and diseases indicated by abnormal biomarkers. Then, biomarkers sensing performances provided by MXenes families and the enhancement strategies are discussed. The method of fabrications toward MXenes integration into various flexible substrates is summarized. Finally, the fundamental challenges and prospects, including portable integration with Internet-of-Thing (IoT) and Artificial Intelligence (AI), are addressed to realize marketization.

Improved thermochromic and photocatalytic activities of F–VO 2 /Nb–TiO 2 multifunctional coating films

Abstract: Multifunctional photocatalytic and thermochromic composites consisting of fluorine-doped vanadium dioxide (F–VO2) and niobium-doped TiO2 (NTO) were prepared by a simple physical mixing. The composites exhibited a higher thermochromic activity and nitrogen oxide (NOx) decomposition activity than that of pristine VO2/NTO. Both VO2 and NTO materials were synthesized using an environmentally friendly soft chemical solvothermal/hydrothermal process, which produced NTO nanoparticles with a controllable morphology and particle size by changing the ratio of ethanol and acetic acid solvent. F–VO2/NTO showed a better multifunctionality of thermochromic and photocatalytic activities than those of VO2/NTO samples. The coexistence coating films showed a better effect on thermochromic and deNOx (NOx reduction) activity than those of double-sided films for F–VO2/NTO samples. The best thermochromic and photocatalytic activities obtained from sample F–VO2/NTO 60 showed the ΔT1500 nm [difference of transmittance (ΔT) at the wavelength of 1500 nm under 25 °C and 95 °C] of up to 29.5% and deNOx activity of up to 40% at λ > 290 nm under mercury lamp irradiation. The use of F–VO2/NTO coexistence coating films showed the appropriateness for multifunctional materials.

One-step hydrothermal synthesis and thermochromic properties of chlorine-doped VO2(M) for smart window application

Abstract: The monoclinic phase of VO2 has promising application as a smart window material because it possesses a reversible metal-to-semiconductor transformation with a critical temperature of 68∘C. The hig...

Advances in Chromogenic Materials and Devices

Abstract: Abstract Chromogenic materials allow the transmittance of visible light and solar energy to be varied under the action of an external stimulus. This paper first discusses buildings related energy savings that can be accomplished by chromogenic technologies, and their beneficial effects on comfort issues. We then summarize recent work on thermochromic VO 2 -based thin films with particular attention to multi-layers of VO 2 and TiO 2 and to new VO 2 :Mg films for which the doping gives significantly lowered absorption of visible light. The final part covers electrochromic materials and devices with foci on coloration efficiency and on durability issues for foil-type constructions based on films of WO 3 and NiO.

Recent research progress on mixed valence state tungsten based materials

Abstract: Synthesis and characterization of tungsten based mixed valence state nanoparticles and their novel applications are reviewed. The mixed valence state tungsten based homogeneous nanomaterials such as bronze structure MxWO3 (M = Na+, K+, Rb+, Cs+, NH4+, etc.) and tungsten sub-oxide W18O49 possess excellent infrared (IR) light shielding property, implying their great potential applications on heat ray shielding and indoor energy saving effect in summer season. Also, some novel properties such as electric conductivity, bio thermal therapy function and electrochromic properties of mixed valence state tungsten based materials are introduced. The design of components, formation of composites and structure control of thin films are expected to realize the property enhancement and candidates for practice application as window materials. The multifunctionality of the mixed valence state based composites also implies great potential on novel applications of various building materials.

Vacancy defect engineering of BiVO4 photoanodes for photoelectrochemical water splitting

Abstract: Photoelectrochemical (PEC) water splitting has been regarded as a promising technology for sustainable hydrogen production. The development of efficient photoelectrode materials is the key to improve the solar-to-hydrogen (STH) conversion efficiency towards practical application. Bismuth vanadate (BiVO4) is one of the most promising photoanode materials with the advantages of visible light absorption, good chemical stability, nontoxic feature, and low cost. However, the PEC performance of BiVO4 photoanodes is limited by the relatively short hole diffusion length and poor electron transport properties. The recent rapid development of vacancy defect engineering has significantly improved the PEC performance of BiVO4. In this review article, the fundamental properties of BiVO4 are presented, followed by an overview of the methods for creating different kinds of vacancy defects in BiVO4 photoanodes. Then, the roles of vacancy defects in tuning the electronic structure, promoting charge separation, and increasing surface photoreaction kinetics of BiVO4 photoanodes are critically discussed. Finally, the major challenges and some encouraging perspectives for future research on vacancy defect engineering of BiVO4 photoanodes are presented, providing guidelines for the design of efficient BiVO4 photoanodes for solar fuel production.