Nanoparticles are regarded as a major step forward to achieving the miniaturisation and nanoscaling effects and properties that have been utilised by nature for millions of years. The chemist is no longer observing and describing the behaviour of matter but is now able to manipulate and produce new types of materials with specific desired physicochemical characteristics. Such materials are receiving extensive attention across a broad range of research disciplines. The fusion between nanoparticle and nanoporous materials technology represents one of the most interesting of these rapidly expanding areas. The harnessing of nanoscale activity and selectivity, potentially provides extremely efficient catalytic materials for the production of commodity chemicals, and energy needed for a future sustainable society. In this tutorial review, we present an introduction to the field of supported metal nanoparticles (SMNPs) on porous materials, focusing on their preparation and applications in different areas.

Carbon-based structures are the most versatile materials used in the modern field of renewable energy (i.e., in both generation and storage) and environmental science (e.g., purification/remediation). However, there is a need and indeed a desire to develop increasingly more sustainable variants of classical carbon materials (e.g., activated carbons, carbon nanotubes, carbon aerogels, etc.), particularly when the whole life cycle is considered (i.e., from precursor "cradle" to "green" manufacturing and the product end-of-life "grave"). In this regard, and perhaps mimicking in some respects the natural carbon cycles/production, utilization of natural, abundant and more renewable precursors, coupled with simpler, lower energy synthetic processes which can contribute in part to the reduction in greenhouse gas emissions or the use of toxic elements, can be considered as crucial parameters in the development of sustainable materials manufacturing. Therefore, the synthesis and application of sustainable carbon materials are receiving increasing levels of interest, particularly as application benefits in the context of future energy/chemical industry are becoming recognized. This review will introduce to the reader the most recent and important progress regarding the production of sustainable carbon materials, whilst also highlighting their application in important environmental and energy related fields.

Porous carbon materials are ubiquitous with a wide range of technologically important applications, including separation science, heterogeneous catalyst supports, water purification filters, stationary phase materials, as well as the developing future areas of energy generation and storage applications. Hard template routes to ordered mesoporous carbons are well established, but whilst offering different mesoscopic textural phases, the surface of the material is difficult to chemically post-modify and processing is energy, resource and step intensive. The production of carbon materials from biomass (i.e. sugars or polysaccharides) is a relatively new but rapidly expanding research area. In this tutorial review, we compare and contrast recently reported routes to the preparation of porous carbon materials derived from renewable resources, with examples of our previously reported mesoporous polysaccharide-derived "Starbon" carbonaceous material technology.

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The outstanding potential of mesoporous carbonaceous materials [1] requires a methodology that grants control over their surface chemistry and the distribution of pore sizes. The best current method that achieves control over pore-size distribution is the templating method. A typical procedure [1c] involves filling mesoporous silica with a carbon precursor (e.g. sucrose), which is subsequently carbonized through a series of high-temperature processes. The template is then removed by using hydrofluoric acid or caustic soda. The resultant activated carbons produced by this method possess wellordered mesoporous structures with a large specific volume and physical properties amenable to a broad range of applications.[2] However, highly aggressive chemicals involved limit this approach to the production of stable graphitic carbons with inert hydrophobic surfaces. [3] To functionalize and open up new chemistry, further difficult chemical modifications are required. This is at the cost of reducing the availability of the mesopores.[4]Herein we report a novel approach for the generation of a new family of mesoporous carbonaceous materials with surfaces ranging from hydrophilic to hydrophobic, which is controlled by the degree of carbonization. The method utilizes the natural ability of the amylose and amylopectin polymer chains within the starch granules to assemble into an organized nanoscale lamellar structure, which consists of crystalline and amorphous regions.[5] Our strategy was to synthesize mesoporous carbons (hereinafter referred to as "starbons") by using mesoporous expanded starch [6] as the precursor without the need for a templating agent. This process is gentle and provides the opportunity to produce a whole range of mesoporous carbon-based materials from starch to activated carbon, including amorphous oxygencontaining carbons that have many applications, [7] such as catalysis, [7a, b] adsorption, [7c] and medicine, [7d, e] owing to their varied surface functionalities.The approach described is illustrated in Scheme 1. First, a simple process of gelatization in water opens up and disorders the dense biopolymer network, [8] after which it partially recrystallizes during a process of retrogradation.[9] Exchanging water with a lower-surface-tension solvent (usually ethanol) prevents collapse of the network structure during the drying process. After drying, the expanded mesoporous starch is obtained. In the final stage of the process, mesoporous starch is doped with a catalytic amount of organic acid (e.g. para-toluenesulfonic acid) and heated under vacuum. This enables fast carbonization and fixing of the mesoporous structure. Heating at different temperatures, ranging from 150 to 700 8C has produced a variety of mesoporous materials from amorphous carbons to graphite-like activated carbons. Native starch granules do not produce mesoporous materials when carbonized. This indicates that the formation of expanded starch as a precursor to starbon is crucial.

Research into renewable bioresources at York and elsewhere is demonstrating that by applying green chemical technologies to the transformation of typically low value and widely available biomass feedstocks, including wastes, we can build up new environmentally compatible and sustainable chemicals and materials industries for the 21st century. Current research includes the benign extraction of valuable secondary metabolites from agricultural co-products and other low value biomass, the conversion of nature's primary metabolites into speciality materials and into bioplatform molecules, as well as the green chemical transformations of those platform molecules. Key drivers for the adoption of biorefinery technologies will come from all stages in the chemical product lifecycle (reducing the use of non-renewable fossil resources, cleaner and safer chemical manufacturing, and legislative and consumer requirements for products), but also from the renewable energy industries (adding value to biofuels through the utilisation of the chemical value of by-products) and the food industries (realising the potential chemical value of wastes at all stages in the food product lifecycle).

A systematic investigation of the interaction of microwave irradiation with microcrystalline cellulose has been carried out, covering a broad temperature range (150 → 270 °C). A variety of analytical techniques (e.g., HPLC, (13)C NMR, FTIR, CHN analysis, hydrogen-deuterium exchange) allowed for the analysis of the obtained liquid and solid products. Based on these results a mechanism of cellulose interaction with microwaves is proposed. Thereby the degree of freedom of the cellulose enclosed CH2OH groups was found to be crucial. This mechanism allows for the explanation of the different experimental observations such as high efficiency of microwave treatment; the dependence of the selectivity/yield of glucose on the applied microwave density; the observed high glucose to HMF ratio; and the influence of the degree of cellulose crystallinity on the results of the hydrolysis process. The highest selectivity toward glucose was found to be ~75% while the highest glucose yield obtained was 21%.

Combined computational screening and practical assessment of >10 000 solvents for the sustainable liquid exfoliation of graphite to graphene.