Energy, water, and food shortages, along with irreversible environmental damage and climate changes, are bound to happen within a decade if the current course of action is maintained, preparing the “perfect storm” – a chain of interrelated events that could lead to major stress on the global system.

Energy plays a central role in the complex balance between humankind and the planet: poor strategies for the energy system will lead to disaster; but immediate, radical action can still mitigate what will otherwise be an unprecedented crisis. Reduction of the carbon intensity at the level of primary energy demand is one of the most impactful strategies. Current actions toward this goal, however, including the Nationally Determined Contributions (i.e., the climate actions pledged by the countries that ratified the Paris Agreements), are far from being adequate, and a much stronger effort is required. In this perspective, we draw inspiration from a visionary scientist of the past century, who pioneered the idea of a society powered by solar energy, and show, by a critical presentation of energy and carbon emission data, how this vision is now coming true. We focus our attention in particular to photovoltaics and analyze the factors that make it one of the key energy sources for the short and for the long term: economical convenience, the opening of very large markets, and the push by key players of the energy system.

Detailed report on MOFs for CO2 adsorption on the basis of ligands employed, OMSs, and structures. Systematic report on the high- and low-pressure CO2 capture. Report on the mechanism of CO2 capture.

A review on the promising field of MOF-based carbon capture and storage is presented. We discuss here the main features of MOFs applicable for CO2 capture and separation, the linker functionalization role, and the most important CO2-binding sites as also the most efficient and significant technologies, and a systematic report on the high- and low-pressure CO2 capture.

This perspective article summarizes the operational principles of dual-ion batteries and highlights the main issues in the interpretation and reporting of their electrochemical performance.

Secondary dual-ion batteries (DIBs) are emerging stationary energy storage systems that have been actively explored in view of their low cost, high energy efficiency, power density, and long cycling life. Nevertheless, a critical assessment of the literature in this field points to numerous inaccuracies and inconsistencies in reported performance, primarily caused by the exclusion of the capacity of used electrolytes and the use of non-charge-balanced batteries. Ultimately, these omissions have a direct impact on the assessment of the energy and power density of DIBs. Aiming to secure further advancement of DIBs, in this work, we critically review current research pursuits and summarize the operational mechanisms of such batteries. The particular focus of this perspective is put on highlighting the main issues in the interpretation and reporting of the electrochemical performance of DIBs. To this end, we survey the prospects of these stationary storage systems, emphasizing the practical hurdles that remain to be addressed.

Environmental concerns deriving from fossil fuel dependency are driving an energy transition based on sustainable processes to make fuels and chemicals. Solar hydrogen is the pillar of this new green economy, but the technological readiness level of PV electrolysis and direct photoelectrochemical (PEC) electrolysis are still too low to allow broad commercialization. Direct conversion through PEC technology has more potential in the medium–long term but must be first guided by the scientific enhancements to improve device efficiencies. For this purpose, in situ and operando photoelectrochemistry will guide the discovery of new materials and processes to make solar fuels and chemicals in PEC cells.

The use of advanced in situ and operando characterizations under working photoelectrochemical (PEC) conditions is reviewed here and anticipated to be a fundamental tool for achieving a basic understanding of new PEC processes and for enabling the large-scale development of PEC technology by 2050, thus delivering fuels and chemicals having zero (or negative) carbon footprint. Hydrogen from solar water splitting is the most popular solar fuel and can be mainly produced by indirect photovoltaic-driven electrolysis (PV electrolysis) and direct photoelectrochemistry. Although PV electrolysis has already been developed on a level of MW-scale pilot plants, PEC technology, which is much less mature, holds several advantages in the long term over PV-electrolysis systems. The key enabling feature to developing PEC technology is the improvement of the photoelectrode materials which are responsible for the absorption of light, and transport of the photo-generated charge carriers to drive the electrochemical surface reaction. These processes are often complex and multistep, spanning multiple timescales and following the simultaneous detection of photoelectrodes modification and formation of reaction intermediates/products can be achieved using eight well-known characterization techniques here presented.

A liquid-state pyroelectric energy harvester is described and a remarkable capacity to convert a thermal gradient into electrical energy is demonstrated.

Increasing the sustainability of energy generation can be pursued by harvesting extremely low enthalpy sources: low temperature differences between cold and hot reservoirs are easily achieved in every industrial process, both at large and small scales, in plants as well as in small appliances, vehicles, natural environments, and human bodies. This paper presents the assessment and efficiency estimate of a liquid-state pyroelectric energy harvester, based on a colloid containing barium titanate nanoparticles and ferrofluid as a stabilizer. The liquid is set in motion by an external pump to control velocity, in a range similar to the one achieved by Rayleigh–Bénard convection, and the colloid reservoir is heated. The colloid is injected into a Fluorinated Ethylene Propylene pipe where titanium electrodes are placed to collect electrical charges generated by pyroelectricity on the surface of the nanoparticles, reaching 22.4% of the ideal Carnot efficiency of a thermal machine working on the same temperature drop. The maximum extracted electrical power per unit of volume is above 7 mW/m3 with a ΔT between electrodes of 3.9 K.

We report a significant advance in thermally insulating transparent materials: silica-based monoliths with controlled porosity which exhibit the transparency of windows in combination with a thermal conductivity comparable to aerogels.

The lack of transparent, thermally insulating windows leads to substantial heat loss in commercial and residential buildings, which accounts for ~4.2% of primary US energy consumption annually. The present study provides a potential solution to this problem by demonstrating that ambiently dried silica aerogel monoliths, i.e., ambigels, can simultaneously achieve high optical transparency and low thermal conductivity without supercritical drying. A combination of tetraethoxysilane, methyltriethoxysilane, and post-gelation surface modification precursors were used to synthesize ambiently dried materials with varying pore fractions and pore sizes. By controlling the synthesis and processing conditions, 0.5–3 mm thick mesoporous monoliths with transmittance >95% and a thermal conductivity of 0.04 W/(m K) were produced. A narrow pore size distribution, <15 nm, led to the excellent transparency and low haze, while porosity in excess of 80% resulted in low thermal conductivity. A thermal transport model considering fractal dimension and phonon-boundary scattering is proposed to explain the low effective thermal conductivity measured. This work offers new insights into the design of transparent, energy saving windows.

In the rural areas of the eastern Amhara region where livelihoods are predominantly based on agriculture with almost all the rural people earning their income from agriculture, awareness toward clean energy, and efficient appliances is at a very infant stage. As an indication, the research comes up with energy utilization is mainly of biomass-based with traditional stoves of very low efficiency. However, the future demand of the community toward the clean and improved efficient appliances has got a better preference over other energy technologies. Regarding the factor in determining the energy and energy appliance type choice, accessibility is found as the major reason.

The type of energy sources and energy technologies utilized for cooking and lighting have their own effect on health, environmental degradation, and overall economic development. Therefore, the primary objective of this study was to analyze the general trend of household energy source and energy technology utilization in rural areas of the Eastern Amhara region. The study utilized primary and secondary data collected over stratified systematically sampled households and from energy experts in the area. The study examined the utilization of various forms of energy and energy technology for the most common household energy-intensive processes (injera baking and stew cooking) as well as lighting. The development of different estimates across the whole population of the study region to indicate the relations among different factors was done through different statistical approaches; and the finding of the analysis revealed that 57.7% of the energy share is biomass-based firewood from which 99.5% of this source was used only for food preparation. The two main determinant factors of the community in selecting the energy types are found to be accessibility and health impact.

Hydrogen is a versatile energy storage medium with significant potential for integration into the modernized grid.

Advanced materials for hydrogen energy storage technologies including adsorbents, metal hydrides, and chemical carriers play a key role in bringing hydrogen to its full potential.

The U.S. Department of Energy Hydrogen and Fuel Cell Technologies Office leads a portfolio of hydrogen and fuel cell research, development, and demonstration activities, including hydrogen energy storage to enable resiliency and optimal use of diverse domestic energy resources.

Today, the technology around generating and storing efficient and sustainable energy is rapidly evolving and hydrogen technologies offer versatile options. This perspective provides an overview of the U.S. Department of Energy's (DOE) Hydrogen and Fuel Cell Technologies Office's R&D activities in hydrogen storage technologies within the Office of Energy Efficiency and Renewable Energy, with a focus on their relevance and adaptation to the evolving energy storage needs of a modernized grid, as well as discussion of identified R&D needs and challenges. The role of advanced materials research programs focused on addressing energy storage challenges is framed in the context of DOE's H2@Scale initiative, which will enable innovations to generate cost-competitive hydrogen as an energy carrier, coupling renewables, as well as nuclear, fossil fuels, and the grid, to enhance the economics of both baseload power plants and intermittent solar and wind, to enhance resiliency and avoid curtailment. Continued growth and engagement of domestic and international policy stakeholders, industry partnerships, and economic coalitions supports a positive future outlook for hydrogen in the global energy system.

The electrification of organic syntheses is a vividly growing research field and has attracted tremendous attention by the chemical industry. This review highlights aspects of electrosynthesis that are rarely addressed in other articles on the topic: the energy consumption and energy efficiency of technically relevant electro-organic syntheses.

Four examples on different scales are outlined.

Electro-organic synthesis has experienced a renaissance within the past years. This review addresses the energy efficiency or energy demand of electrochemically driven transformations as it is a key parameter taken into account by, for example, decision makers in industry. The influential factors are illustrated that determine the energy efficiency and discussed what it takes for an electrochemical process to be classified as “energy efficient.” Typical advantages of electrosynthetic approaches are summarized and characteristic aspects regarding the efficiency of electro-organic processes, such as electric energy consumption, are defined. Technically well-implemented examples are described to illustrate the possible benefits of electrochemical approaches. Further, promising research examples are highlighted and show that the conversion of fine chemicals is rather attractive than the electrochemical generation of synthetic fuels.