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This study investigates a range of commercially available γ‐Al2O3 powders by using a combination of integrated experimental techniques. These included general measurements of powder properties by using helium density, BET surface area, and scanning electron microscopy (SEM) analyses. In addition, dynamic light scattering and zeta potential measurements were used to investigate nanoparticle dispersions. Bulk crystal structures were analysed by using comparative X‐ray and neutron powder diffraction (XRD and NPD) analyses. Conventional transmission electron microscopy (TEM) was used to determine particle morphology, particle size, composition, and structure. Aberration‐corrected TEM was used to investigate the crystallinity of nanoparticles including the existence of any surface reconstruction on commonly observed facetted, cubeoctahedral γ‐Al2O3 nanoparticles. From the observation of peak splittings in diffraction data, we favour a description of the γ‐Al2O3 structure based on a distortion of the conventionally accepted face‐centred cubic (Fd$\bar 3$m) structure into a tetragonal I41/amd structure. Distinct differences between TEM, XRD, and NPD data indicate the presence of some cation disorder within a rigid close‐packed oxygen framework. The Rietveld refinement of the NPD data suggests a high level of microstrain of 1.2 %. An improvement to the model is achieved by reducing the aluminium content in the unit cell, which is commensurate with the migration of aluminium ions to the surface and some degree of nonstoichiometry in the particle core. Aberration‐corrected TEM imaging and exit wave reconstruction confirm previous evidence for the presence of enhanced surface contrast at {1 1 1} surface facets, which we associate with the presence of excess cation termination. In addition, these {1 1 1} facets are observed to be heavily stepped. These results may have important implications for the thermal stability of metal catalyst nanoparticles on these high‐surface area supports; the migration of aluminium ions to the surface provides clear evidence of why these materials perform so well as catalyst supports.

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<span lang="EN-US">The purpose of the study was to develop a valid and reliable instrument that can assess green chemistry awareness among secondary schools. This study applied a quantitative approach with a survey design to obtain information related to items and constructs to build an instrument to access student awareness of green chemistry. The study population involved all form four students who are taking a chemistry subject in 85 secondary schools in the State of Melaka, Malaysia. This study involved two phases and all the respondents were selected using a random sampling method. The first phase involved 700 respondents and the second phase involved 500 respondents. The pilot study involved 100 students who were also randomly selected from the same population but not involved in phase I and phase II study. The data obtained were analyzed using Statistical Package for Social Science (SPSS) software. As a result, the Green Chemistry Awareness Instrument (GCAI) was developed. GCAI contains six constructs with a total of 29 items; knowledge (eight items), attitudes (six items), value (eight items), and awareness lighting (seven items). GCAI was found to have good content and construct validity as well as high reliability. Hence, it can assess green chemistry awareness among secondary school students. GCAI also has the advantage of being easily administered.</span>