Cipta Panghegar Supriadi - Academia.edu (original) (raw)

Uploads

Papers by Cipta Panghegar Supriadi

Research paper thumbnail of Techno economic analysis of public solar street light with integrated monitoring system for parking area

INTERNATIONAL CONFERENCE ON MECHANICAL ENGINEERING FOR EMERGING TECHNOLOGIES (ICOMEET 2021)

Research paper thumbnail of Synthesis and Characterization of Carbon Material Obtained from Coconut Coir Dust by Hydrothermal and Pyrolytic Processes

International Journal of Technology, 2017

Since 2004, graphene has risen in popularity owing to its superior properties. However, limits to... more Since 2004, graphene has risen in popularity owing to its superior properties. However, limits to the scale of production methods have rendered graphene a costly material. Moreover, existing production methods require chemicals that are detrimental to the environment. This study uses Coconut Coir Dust (CCD) as a carbon precursor and an intermediate product in the manufacturing of graphene. Firstly, CCD sieved into a 100 mesh was carbonized using a hydrothermal method at temperatures of 235 o C, 250 o C, and 265 o C, for 4 hours. Following this, the resulting solid residue was pyrolyzed at 1000 o C for 2 hours under the protection of nitrogen (N2). The hydrothermal solid residue was labelled CHT (hydrothermal temperature) and the pyrolysis product was named as SP (hydrothermal temperature). Both samples were characterized using SEM, XRD and EDS. In addition, Raman characterization was conducted for SP samples. At the end of the process (SP), the XRD pattern showed two broad peaks centered around 2θ ~24 o and 44 o corresponding to a (002) and (100) graphite plane. This pattern is similar to that of reduced-graphene oxide. SEM images showed a sheet-like microstructure is caused by undegraded lignin. A perforated and corrugated sheet formed after pyrolysis, which subsequently confirms the formation of reduced-graphene oxide. Furthermore, the Raman result indicates that higher hydrothermal temperatures lead to an increasing integrated ID/IG ratio. The ratios were 1.62, 1.71 and 1.77, for SP 235, SP 250, and SP 265, respectively. Research results conclude that the carbonaceous material formed through hydrothermal and pyrolytic processes contained a mixture of an amorphous-carbon form and a graphene-like cluster. Results additionally show a similar structure with reduced-graphene oxide.

Research paper thumbnail of The effect of sol-gel derived TiO2 crystallite size to Li4Ti5O12 anode performance in lithium-ion battery

Ionics, 2020

The emerging portable device and electrical vehicle require safe, portable, and high-power energy... more The emerging portable device and electrical vehicle require safe, portable, and high-power energy sources which may be supplied by lithium-ion battery (LIB). The existing carbon anode exhibits several issues in terms of safety such as volume expansion and formation of solid electrolyte interphase (SEI) which can be overcome by applying Li 4 Ti 5 O 12 (LTO) as an anode. However, the low electronic and ionic conductivity are the main bottlenecks of LTO. This research focuses on synthesizing LTO using TiO 2 synthesized through the sol-gel method. Furthermore, the effect of TiO 2 crystalline size will be discussed accordingly. The crystalline size of TiO 2 was tailored by applying calcination temperature at 300°C, 400°C, and 500°C and was heated for 6 h. The crystallite size shown by XRD patterns was 8.01 nm, 13.82 nm, and 27.01 nm, respectively. The best electrochemical properties were exhibited by LTO 300 showing the initial specific capacity of 164 mAh g −1 .

Research paper thumbnail of Techno economic analysis of public solar street light with integrated monitoring system for parking area

INTERNATIONAL CONFERENCE ON MECHANICAL ENGINEERING FOR EMERGING TECHNOLOGIES (ICOMEET 2021)

Research paper thumbnail of Synthesis and Characterization of Carbon Material Obtained from Coconut Coir Dust by Hydrothermal and Pyrolytic Processes

International Journal of Technology, 2017

Since 2004, graphene has risen in popularity owing to its superior properties. However, limits to... more Since 2004, graphene has risen in popularity owing to its superior properties. However, limits to the scale of production methods have rendered graphene a costly material. Moreover, existing production methods require chemicals that are detrimental to the environment. This study uses Coconut Coir Dust (CCD) as a carbon precursor and an intermediate product in the manufacturing of graphene. Firstly, CCD sieved into a 100 mesh was carbonized using a hydrothermal method at temperatures of 235 o C, 250 o C, and 265 o C, for 4 hours. Following this, the resulting solid residue was pyrolyzed at 1000 o C for 2 hours under the protection of nitrogen (N2). The hydrothermal solid residue was labelled CHT (hydrothermal temperature) and the pyrolysis product was named as SP (hydrothermal temperature). Both samples were characterized using SEM, XRD and EDS. In addition, Raman characterization was conducted for SP samples. At the end of the process (SP), the XRD pattern showed two broad peaks centered around 2θ ~24 o and 44 o corresponding to a (002) and (100) graphite plane. This pattern is similar to that of reduced-graphene oxide. SEM images showed a sheet-like microstructure is caused by undegraded lignin. A perforated and corrugated sheet formed after pyrolysis, which subsequently confirms the formation of reduced-graphene oxide. Furthermore, the Raman result indicates that higher hydrothermal temperatures lead to an increasing integrated ID/IG ratio. The ratios were 1.62, 1.71 and 1.77, for SP 235, SP 250, and SP 265, respectively. Research results conclude that the carbonaceous material formed through hydrothermal and pyrolytic processes contained a mixture of an amorphous-carbon form and a graphene-like cluster. Results additionally show a similar structure with reduced-graphene oxide.

Research paper thumbnail of The effect of sol-gel derived TiO2 crystallite size to Li4Ti5O12 anode performance in lithium-ion battery

Ionics, 2020

The emerging portable device and electrical vehicle require safe, portable, and high-power energy... more The emerging portable device and electrical vehicle require safe, portable, and high-power energy sources which may be supplied by lithium-ion battery (LIB). The existing carbon anode exhibits several issues in terms of safety such as volume expansion and formation of solid electrolyte interphase (SEI) which can be overcome by applying Li 4 Ti 5 O 12 (LTO) as an anode. However, the low electronic and ionic conductivity are the main bottlenecks of LTO. This research focuses on synthesizing LTO using TiO 2 synthesized through the sol-gel method. Furthermore, the effect of TiO 2 crystalline size will be discussed accordingly. The crystalline size of TiO 2 was tailored by applying calcination temperature at 300°C, 400°C, and 500°C and was heated for 6 h. The crystallite size shown by XRD patterns was 8.01 nm, 13.82 nm, and 27.01 nm, respectively. The best electrochemical properties were exhibited by LTO 300 showing the initial specific capacity of 164 mAh g −1 .