Heat evolution from silica-supported nano-composite samples under exposure
to hydrogen isotope gas
Akira Kitamura 1,5 , Akito Takahashi 1 , Koh Takahashi 1 , Reiko Seto 1 , Takeshi Hatano 1 ,
Yasuhiro Iwamura 2 , Takehiko Itoh 2 , Jirohta Kasagi 2 ,
Masanori Nakamura 3 , Masanobu Uchimura 3 , Hidekazu Takahashi 3 , Shunsuke Sumitomo 3 ,
Tatsumi Hioki 4 , Tomoyoshi Motohiro 4 , Yuichi Furuyama 5 ,
Masahiro Kishida 6 , Hideki Matsune 6
Technova Inc., 100-0011 Japan,
Research Center for Electron Photon Science, Tohoku University, 982-0826 Japan,
Research Division, Nissan Motor Co., Ltd., 237-8523 Japan,
Green Mobility Research Institute, Institutes of Innovation for Future Society,
Nagoya University, 464-8603 Japan,
Graduate School of Maritime Sciences, Kobe University, 658-0022 Japan,
Graduate School of Engineering, Kyushu University, 819-0395 Japan
Hydrogen isotope absorption by palladium and nickel-based nanocomposite samples has been
examined as a collaborative work using the experimental apparatus installed at Kobe University in
order to share scientific understanding of the anomalous heat effects both at room temperature
(R.T.) and elevated temperatures (E.T.). The samples tested so far include “PSf1” fabricated by M.
Kishida, Kyushu University, and “CNS3” synthesized in Kobe University, whose D (or H)
absorption and heat release characteristics are discussed in the present paper.
The PSf1 sample consists of Pd nanoparticles embedded in silica balls. The detailed description
of this sample will be published elsewhere. The CNS3 sample consists of CuNi 10 nanoparticles
supported by mesoporous silica (mp-silica). It was synthesized from a solution of nickel chloride
and copper chloride containing the mp-silica powder as a suspended material to adsorb Ni and Cu
in nano-pores. After filtration, the mp-silica was annealed at 800 °C for 3 hrs. Each sample
containing 8.4-g-Pd (PSf1) or 1.2-g-Cu and 11.4-g-Ni (CNS3) occupied the 500-cc volume of the
reaction chamber without any filler.
The results of the absorption/heat measurements are summarized as follows in comparison with
those obtained previously for other nano-composite samples:
(1) Heating up to around 200 °C is necessary to reduce the NiO in CNS3 sample.
(2) It is not impossible to ascribe hydrogen absorption and heat evolution in the initial phase at R.T.
to reduction of PdO and hydrogen absorption by Pd nanoparticles in the PSf1 sample.
(3) The reduction of PdO at R.T. was conceived to induce the reduction of NiO as a result of
catalytic effect of Pd, in most of the PdNi system, but the concept did not stand for the heavily
re-oxidized PNZ3r sample that took up only 0.1 D/M of D-gas.
(4) In the E.T. phases, excess heat is observed in the runs with binary nanocomposite samples,
while no excess heat is observed with single-element nanoparticles.
(5) In the CNS3#2 run, the excess heat amounts to 29 MJ/mol-Ni or 0.11 GJ/mol-H without any
observable change in the sample composition, which cannot be explained by any chemical