Daya Shankar Kaul

An Exploration of Future of Bioplastics and Their Physical, Chemical and Biological Characteristics

Recently, petroleum-based plastic has become an integral part of human lives; however, its imperishable nature makes it the leading pollutant in solid waste, creating serious environmental problems. Inadequate plastic waste management increases the toxicity of landfills and causes air and marine pollution. Several initiatives have been started to overcome these challenges. Its replacement with biodegradable plastic is one of the upcoming solutions. Thus, many researchers have developed biodegradable plastics from various biomaterials. Despite such potential, no study has reported the research trend for these materials in the literature. This study is carried out to shed light on the past, present, and future research trends in the bioplastic arena. Such a study is important for bioplastic-related research to be made available at a single source with in-depth analysis. A bibliometric analysis is a tool that is carried out for this purpose. Despite numerous research articles and review papers available in the same field, there are limited reported studies related to the bibliometric analysis of bioplastics. Hence, this study has focused on the bibliographic data of 3802 publications from January 1999 till 1st January 2021, extracted from the Web of Science core collection databases using various combinations of search strings. VOSviewer was used to analyze the bibliographic data. With the help of various analysis techniques available with VOSviewer, many types of analysis (e.g. predominantly used material, tested properties of bioplastic etc.) were carried out. Through thisreview, the development and geographical distribution of the research related to bioplasticshave been investigated.

In recent years, photocatalysts are becoming attractive to researchers in exploring their application for treatment of air pollutants. Exposure to ultra-violet visible (UV–VIS) light on photocatalysts often makes them active in decomposing various toxic materials into less or environment-friendly products. Thus, identification, as well as simple synthesis and processing of photocatalysts, could ultimately lead to technologies for the cost-effective mitigation of environmental hazards. A bibliometric analysis has been carried out here to understand and assess the development in photocatalyst research. The data retrieved from the Scopus database on the topic for 2000–2020 were analyzed to investigate the research activities of the past to foresight the future. Various facets of bibliometry were investigated to produce this holistic article. The contribution of various countries, institutions, and authors were investigated. Numerous facets of photocatalyst such as types of photocatalysts, their modification through metal and non-metal doping, their pollutants treatment potency, types of reactors for photocatalysis, factors influencing treatment performance, and models used for designing reactors were examined. In brevity, substantial growth was observed in the last two decades. Contribution of China, the USA, Japan, and India were notable. Chinese universities contributed majorly to the research. Applied Catalysis B: Environmental Journal was the topic’s main journal and Titanium dioxide was the hotspot in photocatalytic research. The research development, problem disclosure, adopted strategies, and materials explored on the photocatalysis for air pollution treatment over recent years across the world could be insightful to the researchers and eventually will be beneficial to formulate new research strategies. Graphical abstract

In recent years, photocatalysts are becoming attractive to researchers in exploring their application for treatment of air pollutants. Exposure to Ultra-Violet Visible (UV-VIS) light on photocatalysts often makes them active in decomposing various toxic materials into less or environment-friendly products. Thus, the identification, as well as simple synthesis and processing of photocatalysts, could ultimately lead to the technologies for the cost-effective mitigation of environmental hazards. A bibliometric analysis has been carried out here to understand and assess the current trend in photocatalyst research. The data retrieved from the Scopus database on the topic for 2000–2020 were analysed to investigate the research activities of the past to foresight the future. Various facets of bibliometry were investigated to produce this holistic review. The contribution of various countries, institutions and authors were investigated. Numerous facets of photocatalyst such as types of photocatalysts, their modification through metal and nometal doping, their pollutants treatment potency, types of reactors for photocatalysis, factors influencing treatment performance and models used for designing reactors were examined. Substantial growth in the publication has been identified in the last two decades. The research trends, problem statements, adopted strategies, and materials explored on the photocatalysis for air pollution treatment over the recent years across the world could be insightful to the researchers and eventually will be beneficial to formulate new research strategies.

Air pollution becomes severe when air contains small particles, toxic gases, dust and smoke emitted from numerous sources such as vehicles, industries, fires or fumes in harmful amount. Aerosols of highly reflective in nature increases albedo of the earth and thereby cools the surface and thus effectively offsets greenhouse gases warming by about 25-50%; whereas, absorbing type of aerosols absorbs solar radiation hence increases the surface temperature. Absorbing type aerosols are largely present in the urban environment due to presence of relatively larger number of vehicular fleet and subsequent more fossil fuel combustion than in rural area. Excessive inhalation of particulate matter is detrimental to human health as it can lead to asthma, lung cancer and cardiovascular diseases. Thus, it becomes essential to monitor aerosols accurately using affordable device having widespread presence and potential to address the related problematic issues. One of the important parameters in aerosol measurement is aerosol optical depth (AOD). Several instruments and techniques are used to measure AOD such as with satellite and ground based sun-photometry, ground and airborne radiometers and LIDARs which are generally costly and non-portable. Hence, an effort has been made to develop an affordable sun photometer using photo-detectors and light filters which will track the sun automatically and retrieve AOD of that location. Device measurement thus built has been correlated with standard instrument measurement like Microtops Sunphotometer