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Geopolymers could be a promising application of the cement industry as an alternative binder of the Portland cement, which is responsible of 8-10 wt% of the anthropogenic emissions of CO2. Geopolymers could help to reduce the emissions that contribute to the greenhouse effect and improve mechanical and structural properties that actually an ordinary Portland cement has. In this research work, it was studied the raw materials by structural and microstructural analysis including, but not limited to, thermal analysis, scanning electron microscopy, particle size distribution, X-ray diffraction, X-ray fluorescence, surface area by the method BET and Fourier transform infrared spectroscopy. Subsequently the geopolymeric and ordinary materials were synthesized through ten different formulations; these materials were prepared in the form of pastes and mortars according to the ASTM C109/C109M-11 standard, which indicates that the material must be set in a 5 cm-side cubic mold. Once the materials were set, they were cured in a humid environment to complete the reaction that is carried out during curing; this procedure was performed according to the aforementioned standard. After 7, 14 and 28 days of curing, the pastes and mortars were tested by compression tests based on the ASTM E9 standard. The geopolymers were structurally studied by X-ray diffraction, and the geopolymeric pastes were analyzed by the Rietveld method. The results of this investigation showed that the compressive strength of the geopolymers increases with increasing the amount of the alite phase because it acts as a nucleating agent to promote the geopolymerization reaction. The geopolymers matched the compressive strength of ordinary material, which is extremely favorable since it has been shown that the production of the geopolymer generates a lower amount of greenhouse gases.

"La nanociencia y nanotecnología se dedica a la creación de nuevos materiales con propiedades interesantes como dureza, conductividad, propiedades magnéticas. Ahora también, se está estudiando el uso de estos nanomateriales como bloques de construcción para crear nuevos materiales. En este trabajo se estudiaron arreglos ordenados y desordenados: 1) ópalo inverso de carbono y 2) bosques de nanotubos de carbono. Respecto al ópalo inverso de carbono, utilizamos un ópalo con nanopartículas de SiO2 (300 nm) ordenadas de manera FCC como molde para la fabricación de ópalo inverso de carbono. Este ópalo inverso de carbono fue sintetizado mediante la infiltración de una solución conteniendo sacarosa como fuente de carbono; además, en esta misma solución se agrego pirazina como fuente de nitrógeno para así obtener ópalo inverso de carbono dopado con nitrógeno. Por otro lado, utilizamos nanopartículas de SiO2 (10 y 100 nm) desordenadas como molde para sintetizar ópalo inverso de carbono dopado con nitrógeno. Estas muestras se caracterizaron mediante SEM, TEM, espectroscopía Raman, análisis termogravimétrico, adsorción de nitrógeno, difracción de rayos-X y espectroscopía de reflexión óptica. En los resultados obtenidos observamos ligeros cambios en la estructura de las muestras dependiendo de la concentración del dopaje, también observamos el corrimiento del pico de reflexión óptica dependiente a la concentración nitrógeno en la muestra; el corrimiento hacia el azul del pico de reflexión óptica dependiente a la concentración nitrógeno en la muestra. Posteriormente, realizamos el estudio de las propiedades físicas de ópalo inverso dopado con diferente contenido de nitrógeno y tamaño de poro. En general, variando la concentración de nitrógeno y el tamaño de poro se puede variar controladamente sus propiedades físicas como la resistencia, emisión de campo, magnetoresistencia y magnetización. La resistencia se variar desde 0.30 hasta 0.02  cm y dependiendo de su nivel de dopaje el mecanismo de transporte electrónico puede variar. En magnetoresistencia (MR) hay una transición de MR positivo a MR negativo, al variar de bajas hacia altas temperaturas. Así también, la magnetización de las muestras exhiben una transición de paramagnético a diamagnético al incrementar la temperatura; la temperatura de transición es más alta para poros más pequeños." "Nanoscience and nanotechnology are dedicated to the creation of new materials with interesting properties like hardness, conductivity, magnetic properties, among others. Now, there is also interest in the use of these materials as building blocks to create new materials. In this work ordered and disordered arrays were studied: 1) carbon inverse opal and 2) carbon nanotube forests. Regarding the carbon inverse opal, we used an opal with SiO2 nanoparticles (300 nm) ordered in a FCC manner as a template for the fabrication of carbon inverse opal. This carbon inverse opal was synthesized by the infiltration of a solution containing sucrose as a carbon source; also, in this same solution we added pyrazine as a nitrogen source to obtain nitrogen doped carbon inverse opal. On another hand, we used disordered SiO2 nanoparticles as a template to synthesize nitrogen doped carbon inverse opal. These samples were characterized by SEM, TEM, Raman spectroscopy, thermogravimetric analysis, nitrogen adsorption, X-ray diffraction and optical reflection spectroscopy. In the obtained results we observed slight changes in the structure depending on the doping concentration, also we observed the shift of the optical reflection peak depending upon the nitrogen concentration in the sample; observed a blue shift of the optical reflection peak dependent on the nitrogen concentration in the sample. Furthermore, we realized the study of the physical properties of the carbon inverse opal with different contents of nitrogen and pore size. In general, varying the nitrogen concentration and pore size it is possible to vary in a controlled manner the physical properties such as resistance, field emission, magnetoresistance and magnetization. The resistance was varied between 0.30 down to 0.02  cm and depending upon the degree of doping the transport mechanism of electrons may vary. In magnetoresistance (MR) there is a transition from positive MR to negative MR, when varying from low to high temperatures. Also, the magnetization of the samples exhibits a transition from paramagnetic to diamagnetic when increasing the temperature; the transition temperature is higher for smaller pore size. Finally, the carbon inverse opal doped with nitrogen was used as an acetone, ethanol and chloroform sensor, showing that doping with nitrogen effectively increases the sensing response signal."